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All Free UK Trade Calculators

Browse all 757 free calculators across 32 categories. Every tool uses metric measurements, UK product sizes, and UK building regulations.

Calculate plaster, plasterboard, rendering materials and more for any UK project.

Plaster Coverage Calculator

Calculate how many bags of plaster you need for any wall or ceiling area.

Plasterboard Calculator

Work out how many plasterboard sheets you need for your room.

Skim Coat Calculator

Calculate multi-finish plaster needed for skim coating walls and ceilings.

Rendering Calculator

Calculate sand and cement quantities for external rendering.

Dot and Dab Calculator

Work out adhesive needed for dot and dab plasterboard fixing.

Plaster Bead Calculator

Calculate angle bead and stop bead lengths for your plastering job.

Coving Calculator

Work out coving lengths and adhesive needed for any room.

Artex Removal Cost Estimator

Estimate the cost of removing Artex from ceilings and walls.

Dry Lining Calculator

Calculate materials for dry lining walls including boards, tape and jointing compound.

Plaster Drying Time Estimator

Estimate how long plaster will take to dry based on conditions.

Ceiling Plaster Calculator

Calculate plaster bags for ceilings with adjusted coverage rates for overhead work.

Monocouche Render Calculator

Calculate K Rend, Weber or Parex monocouche render quantities.

Lime Plaster Calculator

Calculate lime plaster and lime putty quantities for period property restoration.

Bonding Coat Calculator

Calculate Thistle Bond-It or bonding coat plaster for walls and ceilings.

Cornice & Coving Calculator

Calculate cornice and coving lengths, adhesive and mitre cuts for any room.

External Render Bead Calculator

Calculate corner bead, stop bead and bellcast bead quantities for external rendering.

K-Rend Silicone Render System Calculator

Calculate full K-Rend silicone render system quantities including primer, basecoat, mesh and topcoat.

Fire-Rated Plasterboard System Calculator

Calculate fire-rated plasterboard systems for 30, 60, 90 and 120 minute fire resistance.

Acoustic Plasterboard System Calculator

Calculate acoustic plasterboard systems with resilient bars for Part E sound insulation.

Insulated Render Board Calculator

Calculate insulated render board quantities for external wall insulation systems.

Pebbledash Calculator

Calculate pebbledash materials including scratch coat, dash aggregate and cement quantities.

Roughcast/Harling Calculator

Calculate roughcast or harling render materials with thrown coat mix ratios.

Render Carrier Board Calculator

Calculate render carrier boards, fixings and basecoat for timber frame render systems.

One Coat Plaster Calculator

Calculate one coat plaster quantities for Thistle MultiFinish and Hardwall on different backgrounds.

Cement Board Substrate Calculator

Calculate cement board, screws, waterproof tape and primer for wet area substrates.

External Wall Insulation System Calculator

Calculate complete EWI system materials from insulation boards to topcoat render.

Venetian Plaster Calculator

Calculate Venetian plaster quantities for multi-coat decorative plastering systems.

Machine Plaster Calculator

Calculate machine-applied spray plaster quantities with pump output rates and team productivity.

Plasterboard Partition Height Calculator

Calculate maximum partition height by stud size, spacing and board layers per BS 5234.

Render Crack Repair Calculator

Calculate render crack repair materials by crack width and repair method.

UK electrical calculators based on BS 7671 18th Edition wiring regulations.

Cable Sizing Calculator

Calculate the correct cable size based on BS 7671 18th Edition regulations.

Voltage Drop Calculator

Check voltage drop complies with UK wiring regulations.

Maximum Demand Calculator

Calculate maximum electrical demand for domestic installations.

Circuit Breaker Sizing Calculator

Determine the correct MCB rating for your circuit.

Socket Spacing Calculator

Plan socket layouts with Part P guidance on spacing and positioning.

Lighting Layout Calculator

Calculate lighting requirements based on lux levels for each room type.

Cable Length Calculator

Estimate total cable length needed from your floor plan dimensions.

RCD Selection Guide

Determine the correct RCD type and rating for your circuit.

Electrical Load Calculator

Calculate the total electrical load for a domestic property.

EV Charger Cable Sizing Calculator

Size cables correctly for electric vehicle charger installations.

Consumer Unit Sizing Calculator

Calculate how many ways your consumer unit needs for your property.

House Rewiring Calculator

Estimate circuits, cable lengths and consumer unit size for a house rewire.

Smoke Alarm Spacing Calculator

Calculate smoke and heat alarm positions to comply with BS 5839-6.

Lighting Circuit Calculator

Calculate light fittings per circuit based on room area, lux level, fitting wattage and circuit rating.

Earth Fault Loop Impedance Calculator

Calculate Zs from Ze and R1+R2 values and validate against BS 7671 maximum Zs tables.

Prospective Fault Current Calculator

Calculate prospective short-circuit and earth fault currents and check against device breaking capacity.

Diversity Calculator

Apply BS 7671 diversity factors to calculate maximum demand for DNO supply applications.

Ring Final Circuit Test Calculator

Validate ring final circuit test readings for R1, Rn and R2 cross-connections.

Bonding Conductor Sizing Calculator

Calculate main and supplementary bonding conductor sizes per BS 7671.

Conduit Fill Calculator

Calculate conduit fill ratio from cable outer diameters and conduit internal area.

Trunking Fill Calculator

Calculate trunking fill from BS 7671 cable factor tables and trunking capacity.

Three-Phase Load Balancing Calculator

Balance circuits across three phases and calculate neutral current and imbalance.

Bathroom Zone Calculator

Determine bathroom electrical zones and IP rating requirements from bath and shower dimensions.

Electric Shower Circuit Calculator

Calculate cable size, MCB rating and voltage drop for electric shower circuits.

Conduit Bending Calculator

Calculate conduit bend dimensions, gain and overall length for 90, 45, offset and saddle bends.

Emergency Lighting Calculator

Calculate emergency lighting spacing and battery duration per BS 5266.

Solar PV System Sizing Calculator

Size a solar PV system from roof area, orientation and annual yield by UK region.

Battery Storage Sizing Calculator

Size battery storage from daily usage profile, solar generation and tariff arbitrage savings.

RCBO Selection Calculator

Select the correct RCBO type and rating for combined MCB and RCD protection.

Cable Tray Sizing Calculator

Size cable trays from cable count and outer diameters with support bracket spacing.

Earthing System Calculator

Calculate earthing system requirements for TN-S, TN-C-S and TT installations.

IP Rating Selection Calculator

Select the correct IP rating from location assessment and BS 7671 external influences.

Power Factor Correction Calculator

Calculate capacitor bank kVAr sizing for power factor correction.

Lighting Lux Level Calculator

Calculate fitting count from CIBSE lux tables using utilisation and maintenance factors.

Cable Voltage Drop by Temperature Calculator

Calculate cable voltage drop with temperature, grouping and thermal insulation correction factors.

Fire Alarm Cable Calculator

Calculate fire alarm cable quantities per BS 5839-1 zone layout with loop resistance checks.

Data Cabling Calculator

Calculate CAT6/6A cable runs, patch panel ports and containment sizing.

Transformer Sizing Calculator

Size transformers from load kVA with impedance voltage and regulation percentage.

Lightning Protection Calculator

Calculate lightning protection requirements per BS EN 62305 risk assessment.

Heating Element Calculator

Calculate heating element resistance, current draw and thermostat rating.

Motor Circuit Calculator

Calculate motor circuit cable size, starter type, overload setting and short-circuit protection.

Harmonic Distortion Calculator

Calculate total harmonic distortion and neutral current from LED and VFD loads.

Outdoor Lighting Circuit Calculator

Calculate outdoor lighting circuits with SWA cable sizing and earth rod for TT systems.

Smart Meter CT Calculator

Select CT ratios and secondary wiring for smart meter installations by maximum demand.

UPS Sizing Calculator

Size UPS systems from critical load VA, runtime requirements and battery Ah calculation.

Pipe sizing, boiler calculations, radiator and heating system tools for UK properties.

Pipe Sizing Calculator

Calculate the correct pipe diameter for your plumbing installation.

Boiler Size Calculator

Determine the right boiler kW output for your UK property.

Hot Water Cylinder Sizing Calculator

Size your hot water cylinder based on household demand.

Radiator Sizing Calculator

Calculate the BTU output needed for each room.

Central Heating System Volume Calculator

Calculate total water volume in your central heating system.

Inhibitor Dosing Calculator

Work out the correct amount of inhibitor for your heating system.

Towel Rail Sizing Calculator

Calculate the right towel rail size for your bathroom.

Underfloor Heating Pipe Calculator

Calculate pipe lengths and spacing for underfloor heating systems.

Expansion Vessel Sizing Calculator

Size the expansion vessel for your sealed heating system.

Heat Pump Sizing Calculator

Calculate the heat pump capacity needed for your property.

Water Pressure Calculator

Calculate water pressure and check if it's adequate for your fixtures.

Waste Pipe Sizing Calculator

Size waste pipes and calculate fall for sinks, baths and toilets per Part H.

Flue Liner Calculator

Calculate flue liner size and length for wood burners and stoves per Document J.

Gas Pipe Sizing Calculator

Calculate gas pipe diameter based on appliance load and pipe run length.

Oil Tank Sizing Calculator

Size an oil storage tank based on annual consumption and delivery schedule.

Radiator BTU Calculator

Calculate BTU output needed for room heating based on dimensions, insulation, windows and room type.

Gas Rate Calculator

Calculate gas rate from meter dial readings with kW gross and net conversion.

Gas Meter Timer Calculator

Calculate gas rate from test dial timing and compare to appliance rated input.

Unvented Cylinder Sizing Calculator

Size unvented hot water cylinders per Part G3 with recovery time and expansion vessel.

TMV Sizing Calculator

Size thermostatic mixing valves per Part G with flow rate and TMV2/TMV3 selection.

Cylinder Heat-Up Time Calculator

Calculate hot water cylinder heat-up time from coil kW and standing losses.

Radiator Balancing Calculator

Calculate radiator balancing settings with flow rates and lock-shield Kv values.

Magnetic Filter Sizing Calculator

Size magnetic filters from system volume with flow rate compatibility and pressure drop.

System Pressurisation Calculator

Calculate fill pressure from static head and expansion vessel pre-charge settings.

Condensate Pipe Calculator

Calculate condensate pipe runs, minimum fall, external insulation and soakaway sizing.

Power Flush Calculator

Calculate power flush chemical doses, flow rates and duration from system volume.

Water Loading Units Calculator

Calculate simultaneous demand from BS EN 806 loading units per outlet type.

TRV Sizing Calculator

Size TRVs from Kv values, flow rates and differential pressure.

Circulating Pump Calculator

Calculate pump duty point from system flow rate and index circuit resistance.

Combi Boiler Flow Rate Calculator

Calculate combi boiler flow rate from kW output at 35C temperature rise.

Cylinder Coil Sizing Calculator

Size cylinder coils for heat pump low-temperature flow with Part L compliance.

Thermal Store Calculator

Calculate thermal store buffer capacity for heat pump cycling and multi-source priority.

Condensing Boiler Efficiency Calculator

Calculate condensing boiler efficiency from return temperature and seasonal SEDBUK/ErP rating.

Pipe Heat Loss Calculator

Calculate pipe heat loss per metre by diameter and insulation thickness per BS 5422.

Domestic Hot Water Demand Calculator

Calculate daily hot water demand by occupancy with peak hour storage sizing per Part G.

System Bypass Sizing Calculator

Size automatic bypass valves for minimum boiler flow and differential pressure.

Pressurised System Safety Calculator

Calculate PRV settings, T&P valve discharge pipe sizing and tundish requirements.

Biomass Boiler Sizing Calculator

Size biomass boilers from heat demand with fuel store calculation and flue sizing per Doc J.

Water Softener Sizing Calculator

Size water softeners from hardness and daily usage with regeneration frequency.

Plumbing First Fix Calculator

Calculate pipe run lengths, fittings and drop points for first fix plumbing layouts.

Central Heating Cleaner Calculator

Calculate central heating cleaner doses and inhibitor re-dose from system volume.

Radiator Pipe Sizing Calculator

Size radiator pipework from cumulative BTU loads along pipe runs.

Stove Flue Calculator

Calculate stove flue diameter, height and ventilation per Document J.

F-Gas Refrigerant Calculator

Calculate F-Gas CO2 equivalent and leak check frequency thresholds.

Heating System Design Temperature Calculator

Look up external design temperatures by UK region for heating system sizing.

Calculate tiles, felt, battens, guttering and all roofing materials for UK roof types.

Roof Tile Calculator

Calculate how many roof tiles you need per m² for your roof.

Ridge Tile Calculator

Work out ridge tile quantities and mortar needed.

Felt and Batten Calculator

Calculate roofing felt and batten quantities for your roof.

Soffit and Fascia Calculator

Work out soffit board and fascia lengths needed.

Gutter Sizing Calculator

Calculate gutter size and downpipe requirements for your roof area.

Lead Flashing Calculator

Calculate lead flashing quantities for valleys, abutments and chimneys.

Roof Area Calculator

Calculate actual roof area from plan dimensions and pitch angle.

Roof Pitch Calculator

Calculate roof pitch angle from rise and run measurements.

Roof Truss Calculator

Estimate truss quantities and spacing for your roof span.

Flat Roof Membrane Calculator

Calculate membrane and insulation needed for flat roof coverings.

Roof Ventilation Calculator

Calculate roof ventilation to comply with UK Building Regulations and BS 5250.

Roof Window Sizing Calculator

Calculate Velux or roof window size and quantity for Part L daylight compliance.

Fascia Board Calculator

Calculate fascia boards, corner trims and fixings for roof perimeter.

Gutter Bracket Calculator

Calculate gutter brackets, outlets, corners and union joints for guttering installation.

Dry Ridge System Calculator

Calculate dry ridge system unions, end caps, roll and gasket by tile profile.

Dry Verge Calculator

Calculate dry verge units, starter kits and end caps from gable length.

Hip Tile Calculator

Calculate hip tile quantities, hip irons and mortar from roof geometry.

Valley Trough Calculator

Calculate valley trough lengths in GRP or lead with overlap and tile-and-a-half count.

Flat Roof Fall Calculator

Calculate firring strip dimensions for flat roof falls at 1:40, 1:60 or 1:80 gradients.

EPDM Rubber Roof Calculator

Calculate EPDM single-ply membrane, adhesive, perimeter trim and water check strips.

GRP Flat Roof Calculator

Calculate GRP fibreglass roof resin, CSM mat, trims and catalyst ratios.

Chimney Flashing Calculator

Calculate lead code, apron, step and back gutter flashing from chimney dimensions.

Slate Roof Calculator

Calculate slate quantities from headlap and gauge with nail count and battens.

Roof Insulation Calculator

Calculate roof insulation thickness by type to achieve target U-values.

Solar Panel Roof Loading Calculator

Check solar panel weight and wind uplift against rafter capacity.

Zinc Standing Seam Calculator

Calculate zinc standing seam sheet widths, clips, underlayer and drip edges.

Roof Lantern Calculator

Calculate roof lantern structural opening, kerb depth and glazing bar spacing.

Roof Snow Load Calculator

Calculate roof snow loads per BS EN 1991-1-3 by altitude and zone.

Roof Wind Load Calculator

Calculate roof wind loads per BS EN 1991-1-4 with pressure coefficients by zone.

Eaves Ventilation Calculator

Calculate eaves ventilation area per BS 5250 with soffit vent and ridge vent pairing.

Screed, tiles, laminate, carpet and all flooring material calculators.

Screed Calculator

Calculate screed volume and sand/cement quantities for floor screeding.

Self-Levelling Compound Calculator

Work out how many bags of self-levelling compound you need.

Floor Tile Calculator

Calculate tiles, adhesive and grout needed for floor tiling.

Laminate Flooring Calculator

Work out how many packs of laminate or engineered flooring you need.

Carpet Calculator

Calculate carpet area, underlay and gripper rod quantities.

Underfloor Heating Coverage Calculator

Calculate UFH mat or cable coverage for your floor area.

Floor Joist Calculator

Size floor joists and calculate spacing based on span and load.

Vinyl Flooring Calculator

Calculate vinyl flooring quantities including wastage allowance.

Floor Levelling Calculator

Estimate compound needed to level an uneven floor.

Skirting Board Calculator

Calculate skirting board lengths and mitre cuts needed for any room.

Floor Prep Calculator

Calculate self-levelling compound, primer and drying time for floor preparation.

Stair Carpet Calculator

Calculate carpet length, area and gripper rods for staircases.

Acoustic Flooring Calculator

Calculate acoustic underlay, adhesive and decoupling mat quantities for sound-rated flooring.

Engineered Wood Flooring Calculator

Calculate engineered wood boards, underlay, expansion gap perimeter and transitions per doorway.

Parquet/Herringbone Calculator

Calculate parquet and herringbone block count with 15% pattern waste and adhesive.

Floor Sanding Calculator

Calculate sanding belts by grit sequence, lacquer coats and gap filler for floor sanding.

Epoxy Resin Floor Calculator

Calculate epoxy resin floor coatings including primer, base coat, aggregate and seal coat.

LVT Flooring Calculator

Calculate LVT tiles or planks, adhesive type and perimeter trim.

Anhydrite Screed Calculator

Calculate anhydrite flow screed volume with pump delivery rate and drying time estimates.

Floor DPM Calculator

Calculate floor DPM roll coverage with lap allowance and tape per joint.

Raised Access Floor Calculator

Calculate raised access floor pedestals, panels and edge trim from grid spacing.

Floor Beam and Block Calculator

Calculate beam and block floor quantities with structural topping and propping centres.

Mezzanine Floor Calculator

Calculate mezzanine floor joists, hangers, deck boards and balustrade from span.

Floor Joist Notching Calculator

Check permitted notch and hole zones in floor joists per Building Regulations.

Threshold and Transition Calculator

Calculate threshold strips and transition profiles by height difference per doorway.

Heated Screed Commissioning Calculator

Calculate heated screed drying time and temperature ramp schedule before flooring.

Solid Wood Floor Calculator

Calculate solid wood T&G boards, secret nails, adhesive and acclimatisation time by species.

Floor Load Capacity Calculator

Calculate safe floor load capacity from joist size and spacing for planned use.

Topsoil, gravel, drainage, fencing, decking and garden material calculators.

Topsoil Calculator

Calculate how many tonnes or bulk bags of topsoil you need.

Gravel Calculator

Work out gravel or aggregate quantities in tonnes and bulk bags.

Type 1 Sub-Base Calculator

Calculate Type 1 MOT sub-base quantities for driveways and paths.

Soakaway Sizing Calculator

Size a soakaway to UK BRE DG 365 standards for your roof area.

Fence Post Spacing Calculator

Calculate fence post quantities and optimal spacing.

Decking Calculator

Calculate decking boards, joists, fixings and all materials needed.

Paving Slab Calculator

Work out how many paving slabs and how much sand/cement you need.

Patio Paving Calculator

Calculate paving slabs, sand, cement and sub-base for patios with pattern and wastage options.

Raised Bed Soil Calculator

Calculate soil volume needed to fill raised garden beds.

Drainage Fall Calculator

Calculate the correct gradient and fall for drainage pipes.

French Drain Calculator

Calculate gravel, membrane and pipe needed for a French drain.

Retaining Wall Calculator

Estimate blocks or sleepers needed for a retaining wall.

Turf Calculator

Calculate turf rolls or grass seed needed for your lawn area.

Artificial Grass Calculator

Calculate artificial grass, sub-base, membrane and fixings for your garden.

Block Paving Calculator

Calculate block paving quantities for driveways and patios with pattern wastage.

Aggregate Calculator

Calculate gravel, sand and aggregate in tonnes and bulk bags for any project.

Shed Base Calculator

Calculate materials for a shed base - concrete, paving slabs or gravel pad.

Pergola Calculator

Calculate timber, fixings and concrete for a garden pergola.

Gabion Wall Calculator

Calculate gabion baskets, fill stone and membrane for a gabion wall.

Rainwater Harvesting Calculator

Size a rainwater harvesting tank based on roof area and rainfall.

Driveway Calculator

Calculate materials for gravel, block paving, tarmac, resin or concrete driveways.

Weed Membrane Calculator

Calculate weed membrane area, overlap and fixing pins for any ground cover project.

Garden Edging Calculator

Calculate edging strips, stakes and fixings for lawns, borders and paths.

Bark Mulch Calculator

Calculate bark mulch volume in bulk bags and litres for garden beds.

Lawn Feed Calculator

Calculate lawn feed, weed killer and seed quantities by lawn area.

Pond Liner Calculator

Calculate pond liner size with overlap allowance for any pond shape.

Pond Volume Calculator

Calculate pond water volume in litres for pumps, filters and treatments.

SuDS Attenuation Calculator

Calculate SuDS attenuation storage volume from greenfield runoff rate and storm duration.

Permeable Paving Calculator

Calculate permeable paving sub-base depth, void ratio, blocks and geotextile.

Kerb and Edging Calculator

Calculate kerb units, haunching concrete and bedding mortar per metre.

Dropped Kerb Calculator

Calculate dropped kerb crossover materials, tactile paving and council fee estimate.

Resin Bound Driveway Calculator

Calculate resin, aggregate and primer for resin bound driveways at 18mm depth.

Composite Decking Calculator

Calculate composite decking boards, clips, joists and fascia with expansion gaps.

Tarmac Driveway Calculator

Calculate tarmac tonnage for base and wearing courses with edge restraint.

Concrete Driveway Calculator

Calculate concrete driveway slab, mesh, expansion joints and formwork.

Sleeper Retaining Wall Calculator

Calculate railway sleeper retaining wall materials with rebar pins and drainage.

Garden Steps Calculator

Calculate garden steps from level change with treads, risers and foundation concrete.

Garden Irrigation Calculator

Calculate garden irrigation zone flow rates, pipe diameter and controller sizing.

Swale Calculator

Calculate SuDS swale storage volume, cross-section and check dam spacing.

Rain Garden Calculator

Calculate rain garden area, soil depth, filter media and overflow pipe sizing.

Outdoor Kitchen Calculator

Calculate outdoor kitchen plinth blocks, worktop and utility supply routing.

Fire Pit Calculator

Calculate fire pit materials including fire bricks, mortar, drainage and cap stones.

Land Drainage Calculator

Calculate herringbone land drainage layout, collector pipe and gravel trench quantities.

Groundwork Excavation Calculator

Calculate excavation cut volume with soil swell factor, lorry loads and disposal.

Car Park Surfacing Calculator

Calculate car park surfacing materials, bay markings, sub-base and drainage.

Concrete, blocks, bricks, mortar and structural material calculators.

Concrete Volume Calculator

Calculate concrete volume in m³ for foundations, slabs and paths.

Concrete Mix Calculator

Work out cement, sand and aggregate ratios for different concrete mixes.

Block Calculator

Calculate how many concrete blocks you need per m² of wall.

Brick Calculator

Work out how many bricks you need for walls, piers and features.

Mortar Calculator

Calculate sand and cement quantities for bricklaying and blockwork mortar.

Foundation Calculator

Estimate foundation depth, width and concrete volume needed.

Lintel Sizing Calculator

Determine the correct lintel size for your opening width and load.

Padstone Sizing Calculator

Calculate padstone dimensions for steel beam bearings.

Rebar Calculator

Calculate reinforcement bar quantities and spacing for concrete.

Concrete Drying Time Estimator

Estimate concrete curing and drying times based on conditions.

Wall Ties Calculator

Calculate cavity wall tie quantities per PD 6697 for new build and remedial work.

DPC Calculator

Calculate damp proof course lengths and rolls for walls and cavity trays.

Timber Span Calculator

Find the right timber size for floor joists, ceiling joists and beams by span.

Cladding Calculator

Calculate cladding boards, battens, membrane and fixings for external walls.

Repointing Calculator

Calculate mortar needed for repointing brickwork.

Acrow Prop Spacing Calculator

Calculate Acrow prop quantities and spacing for temporary structural support.

Opening Deduction Calculator

Calculate area to deduct for doors and windows from gross wall area.

Wall Cladding Calculator

Calculate cladding boards, battens and fixings for external wall cladding.

Window Lintel Calculator

Calculate lintel size, bearing requirements, cavity tray and DPC for window and door openings.

Steel Beam (RSJ) Calculator

Calculate steel beam size from UDL, moment capacity and padstone sizing.

Reinforcement Mesh Calculator

Calculate reinforcement mesh sheets by type with overlap and chairs per m².

Underpinning Calculator

Calculate underpinning pin sequence, volume and mass concrete quantities.

Cavity Tray Calculator

Calculate cavity tray lengths, weep holes and stop ends for openings.

Movement Joint Calculator

Calculate expansion joint positions for clay and concrete blockwork walls.

Concrete Curing Calculator

Calculate concrete strength gain and formwork striking time by temperature and mix.

Raft Foundation Calculator

Calculate raft foundation area, edge beam depth, reinforcement and concrete volume.

Trench Fill Foundation Calculator

Calculate trench fill foundation concrete volume and cost comparison vs strip foundation.

Pile Foundation Calculator

Calculate pile count from total load, pile spacing and ground beam quantities.

Concrete Grade Selector

Select the correct concrete grade by application from foundations to exposed concrete.

Ready-Mix Concrete Order Calculator

Calculate ready-mix concrete truck loads with waste allowance and pump comparison.

Engineered Joist Calculator

Select I-joist or Posi-joist size from span tables with web hole zones and hangers.

Brick Pier Calculator

Calculate brick pier materials per course with foundation pad sizing.

Structural Opening Calculator

Calculate temporary support, needle positions, lintel and making good for structural openings.

Ground Bearing Pressure Calculator

Check foundation bearing pressure against allowable soil capacity by type.

Concrete Pumping Calculator

Calculate concrete pump reach, line friction loss and delivery rate.

Concrete Stair Calculator

Calculate concrete stair formwork, rebar and concrete volume from cross-section.

Blockwork Wall Calculator

Calculate blockwork wall materials including blocks, mortar, wall ties and DPC.

Resin Anchor Calculator

Calculate resin anchor bore diameter, embedment depth and cartridge volume.

Concrete Kerb Foundation Calculator

Calculate concrete kerb haunching and bedding volume per metre run.

Brick Arch Calculator

Calculate brick arch geometry, voussoir count, skewback angle and temporary centre.

Paint coverage, wallpaper, primer and decorating material calculators.

Paint Coverage Calculator

Calculate how many litres of paint you need for walls and ceilings.

Wallpaper Calculator

Work out how many rolls of wallpaper you need for any room.

Primer Coverage Calculator

Calculate primer quantities for walls, wood and metalwork.

Wood Stain Calculator

Calculate wood stain or varnish needed for decking, fences and furniture.

Masonry Paint Calculator

Calculate exterior masonry paint for outside walls.

Ceiling Paint Calculator

Calculate paint needed specifically for ceilings with correct coverage rates.

Radiator Paint Calculator

Calculate specialist radiator paint for single panel, double panel and column radiators.

Floor Paint Calculator

Calculate floor paint for garages, workshops and interior floors.

Intumescent Paint Calculator

Calculate fire protection paint for steelwork and timber per Part B.

Anti-Mould Paint Calculator

Calculate anti-mould and anti-condensation paint for bathrooms, kitchens and damp areas.

Lining Paper Calculator

Calculate lining paper rolls, paste and pattern match waste by wall area.

Spray Paint Calculator

Calculate spray paint coverage with thinning ratio and overspray waste factor.

Epoxy Floor Coating Calculator

Calculate two-part epoxy floor coating with primer, build coat and seal coat.

Gloss/Satinwood Calculator

Calculate gloss and satinwood paint for doors, frames, skirting and architrave.

Metal Protective Paint Calculator

Calculate zinc primer, undercoat and topcoat for metal surfaces and steelwork.

Textured Masonry Coating Calculator

Calculate textured masonry coating with stabiliser primer and crack filler.

Limewash Calculator

Calculate limewash multi-coat quantities with casein additive for exteriors.

Fence Staining Calculator

Calculate fence stain for panels and posts with both-sides and end-grain factors.

Exterior Wood Oil Calculator

Calculate exterior wood oil coverage by timber species with recoat intervals.

Damp Seal/Stain Block Calculator

Calculate stain block primer for damp stains with drying time between coats.

Fireproof Paint Calculator

Calculate fireproof intumescent paint by DFT, Hp/A section factor and fire rating.

Decorator's Prep Calculator

Calculate sugar soap, filler, caulk and sandpaper for decorating preparation.

U-value, heat loss, insulation thickness and energy efficiency calculators.

U-Value Calculator

Calculate the U-value of wall, floor and roof constructions.

Insulation Thickness Calculator

Determine the insulation thickness needed to meet UK Building Regulations.

Heat Loss Calculator

Calculate room-by-room heat loss for heating system sizing.

Cavity Wall Insulation Calculator

Estimate cavity wall insulation quantities and potential savings.

Loft Insulation Calculator

Calculate loft insulation rolls needed for your loft area.

EPC Rating Estimator

Estimate your property's Energy Performance Certificate rating.

Draught-Proofing Calculator

Calculate draught-proofing materials for doors and windows.

Solar Panel Savings Estimator

Estimate solar panel energy generation and cost savings for UK homes.

Floor Insulation Calculator

Calculate floor insulation thickness and quantities to meet Building Regs Part L.

Pipe Insulation Calculator

Calculate pipe insulation lengths and thickness per BS 5422 standards.

Sound Insulation Calculator

Calculate acoustic insulation and resilient bars for Part E compliance.

External Wall Insulation Calculator

Calculate EWI boards, adhesive, mesh and render for external wall insulation.

Window Energy Savings Calculator

Calculate energy and cost savings from upgrading windows.

Solar Battery Storage Calculator

Size a solar battery system based on daily usage, panel output and tariff.

EV Charging Time Calculator

Calculate electric vehicle charging time from battery size and charger power.

Airtightness Estimator

Estimate building airtightness from leakage paths and check against Part L targets.

MVHR Ductwork Calculator

Calculate MVHR ductwork sizes from extract and supply rates with pressure drop.

Thermal Bridge Calculator

Calculate thermal bridge psi-values and heat loss at junctions for SAP assessment.

Radon Protection Calculator

Determine radon protection level by location with membrane and sump kit quantities.

Spray Foam Insulation Calculator

Calculate spray foam insulation thickness and coverage for open and closed cell types.

PIR Board Insulation Calculator

Calculate PIR insulation board thickness from target R-value with boards per m².

Blown-In Insulation Calculator

Calculate blown-in cavity insulation volume, bead bags and injection hole spacing.

Warm Roof vs Cold Roof Calculator

Compare warm roof and cold roof insulation buildups with U-value and condensation risk.

Interstitial Condensation Calculator

Calculate dew point through wall layers to assess interstitial condensation risk.

Energy Payback Calculator

Calculate insulation payback period from U-value improvement and annual energy savings.

Carbon Emission Calculator

Calculate carbon emissions by fuel type from annual energy consumption.

SAP Rating Estimator

Estimate SAP rating from fabric heat loss, heating efficiency and renewables.

Multifoil Insulation Calculator

Calculate multifoil insulation with required air gaps, battens and staple count.

Green Roof Insulation Calculator

Calculate green roof buildup layers from membrane to substrate with weight per m².

Whole House Heat Loss Calculator

Calculate whole house fabric and ventilation heat losses for boiler or heat pump sizing.

Wall tiles, adhesive, grout, shower trays and bathroom calculators.

Wall Tile Calculator

Calculate wall tiles, adhesive and grout for bathrooms and kitchens.

Tile Adhesive Calculator

Work out how much tile adhesive you need for floors and walls.

Grout Calculator

Calculate grout quantities based on tile size and joint width.

Shower Tray Fall Calculator

Calculate the correct fall gradient for a wet room or shower tray.

Bathroom Extraction Rate Calculator

Calculate the required extraction rate for bathroom ventilation.

Wet Room Tanking Calculator

Calculate tanking kit materials for wet room waterproofing.

Underfloor Heating Mat Calculator

Calculate electric UFH mat size, wattage and thermostat for tiled floors.

Ventilation Rate Calculator

Calculate extract ventilation rates per Approved Document F for any room.

Splashback Tile Calculator

Calculate tiles, adhesive and trims for kitchen and bathroom splashbacks.

Tile Trim Calculator

Calculate tile trim lengths, corners and joiners by tile thickness.

Tile Backer Board Calculator

Calculate tile backer boards, screws, waterproof tape and primer.

Large Format Tile Calculator

Calculate large format tile levelling clips, wedges, adhesive trowel size and weight check.

Mosaic Tile Calculator

Calculate mosaic tile sheets, adhesive and grout from room area.

Tile Pattern Calculator

Calculate tile waste percentage by pattern type with cut tile counts.

Tile Waterproofing System Calculator

Calculate tile waterproofing membrane, tape, corners and drain collar.

Bathroom Suite Spacing Calculator

Check bathroom suite clearances and minimum dimensions per Part M.

En-Suite Layout Calculator

Calculate minimum en-suite dimensions by suite type and door swing clearance.

Shower Enclosure Calculator

Calculate shower enclosure glass panels, tray size, waste position and seal lengths.

Wet Room Drainage Calculator

Calculate wet room drainage fall, screed volume, former kit and flow rate.

Bathroom Ventilation Calculator

Calculate bathroom ventilation per Part F with duct sizing and bend capacity reduction.

Bathroom Electrical Zone Calculator

Determine bathroom electrical zones, IP ratings and supplementary bonding requirements.

Walk-In Shower Calculator

Calculate walk-in shower screen, channel drain, tanking area and glass thickness.

Heated Bathroom Floor Calculator

Calculate electric heated bathroom floor mat wattage, thermostat and insulation board.

Bathroom Underfloor Prep Calculator

Calculate bathroom floor buildup layers and check against door threshold height.

Shower Pump Sizing Calculator

Size shower pumps from gravity head, required bar pressure and pipe restriction.

Fence panels, posts, concrete, gravel boards and boundary calculators.

Fence Panel Calculator

Calculate fence panels, posts and fittings for your boundary.

Post and Rail Fence Calculator

Work out posts, rails and fixings for post and rail fencing.

Concrete for Fence Posts Calculator

Calculate postcrete or concrete needed to set fence posts.

Gravel Board Calculator

Calculate gravel boards and clips needed for your fence run.

Trellis Calculator

Work out trellis panels and fixings needed for your garden.

Close Board Fencing Calculator

Calculate featheredge boards, posts, arris rails and fixings for close board fencing.

Garden Wall Calculator

Calculate blocks, bricks, mortar, foundations and coping for a freestanding garden wall.

Fence Post Concrete Calculator

Calculate postcrete bags or concrete volume needed for setting fence posts.

Metal Railing Calculator

Calculate metal railing posts, handrail, infill bars and base plate bolts per Part K.

Chain Link Fence Calculator

Calculate chain link mesh rolls, straining wire and strainer posts.

Acoustic Fence Calculator

Calculate acoustic fence panel density and height for noise reduction.

Palisade Security Fence Calculator

Calculate palisade fence pale count, posts, rail sections and anti-climb specification.

Picket Fence Calculator

Calculate picket count by width and gap, arris rails and post caps.

Brick Boundary Wall Calculator

Calculate brick boundary wall materials with piers, foundation and coping stones.

Gate Sizing Calculator

Calculate gate opening dimensions, hinge type, auto-closer and drop bolt for Part M.

Hedge Planting Calculator

Calculate hedge plants per metre, trench depth and rootball volume.

Wire Stock Fence Calculator

Calculate wire stock fence rolls, strainer posts, intermediate posts and staples.

Fence Wind Load Calculator

Calculate fence wind load, post embedment depth and concrete collar for stability.

Area, volume, unit converters and general-purpose construction tools.

Area Calculator

Calculate areas for rectangles, triangles, circles and irregular shapes.

Volume Calculator

Calculate volumes for cubes, cylinders, cones and irregular shapes.

Metres to Feet Converter

Convert between metric and imperial measurements.

Kg to Bags Converter

Convert bulk weights to bag quantities for common building materials.

Cubic Metres to Tonnes Converter

Convert volume to weight for aggregates, sand, soil and more.

Skip Size Guide

Find the right skip size for your project with volume and cost estimates.

Van Payload Calculator

Check if your van can carry the weight of your materials.

Scaffolding Calculator

Estimate scaffolding requirements and hire costs for your project.

Suspended Ceiling Calculator

Calculate ceiling tiles, grid, wall angle and hangers for a suspended ceiling.

Garden Room Calculator

Estimate materials for a self-build garden room or home office.

Ramp Calculator

Calculate ramp length, gradient and handrails for Part M wheelchair access.

Worktop Calculator

Calculate kitchen worktop lengths, joints and edging strips.

Concrete Mixer Loads Converter

Convert concrete volume in m³ to mixer loads for belle and barrow mixing.

Brick to Block Converter

Convert between brick and block quantities for equivalent wall areas.

Tile to Boxes Converter

Convert tile m² coverage to boxes needed for any tile size and box quantity.

VAT Reclaim Calculator

Calculate VAT reclaim on new build self-builds using the DIY VAT431 scheme.

CIS Tax Deduction Calculator

Calculate Construction Industry Scheme tax deductions for subcontractors.

Planning Application Fee Calculator

Calculate UK planning application fees for householder and other applications.

Fire Escape Route Calculator

Calculate maximum travel distances and escape route widths per Approved Document B.

Minimum Room Size Calculator

Check room sizes against NDSS and Housing Act minimum space standards.

Natural Light Calculator

Calculate window-to-floor area ratio for daylight compliance.

Rubble Removal Calculator

Estimate rubble weight and skip size needed for demolition waste.

Waste Tonnage Calculator

Calculate waste tonnage by material type for skip hire and disposal.

Material Weight Calculator

Calculate material weights from volume using density lookup for common building materials.

Waste Factor Calculator

Apply industry waste factors to material quantities by material type.

Grab Lorry Load Calculator

Calculate grab lorry loads from volume with swell factor and weight check.

Permitted Development Checker

Check extension and outbuilding dimensions against permitted development rules.

Party Wall Requirement Checker

Determine Party Wall Act notice requirements from 3m/6m boundary rules.

Asbestos Risk Checker

Assess asbestos risk from property age and material location.

Noise Assessment Calculator

Calculate construction noise levels with distance attenuation and barrier reduction.

Site Welfare Calculator

Calculate CDM site welfare provisions from worker count.

Staircase Compliance Calculator

Check staircase dimensions against Part K rise, going, pitch and headroom limits.

Room Ventilation Calculator

Calculate Part F trickle vent EA, extract rates and purge ventilation by room type.

Building Control Fee Calculator

Calculate building control fees by project type and value band with plan check and inspection.

Section 106 Estimator

Estimate CIL rates, affordable housing percentage and infrastructure contributions.

Staircase, stud wall, door lining and balustrade calculators for UK building projects.

Staircase Calculator

Calculate stair dimensions compliant with UK Building Regulations Part K.

Stud Wall Calculator

Calculate studs, plasterboard and fixings for partition walls.

Door Lining & Architrave Calculator

Calculate door lining sets and architrave for multiple doors.

Spindle Spacing Calculator

Calculate baluster spacing compliant with 100mm sphere rule.

Shelving Calculator

Calculate shelf lengths, brackets, fixings and load capacity for wall shelving.

Plywood & OSB Sheet Calculator

Calculate plywood or OSB sheets needed with cutting optimisation.

Dado Rail Calculator

Calculate dado rail lengths, mitre joints and fixings for any room.

Picture Rail Calculator

Calculate picture rail lengths, mitre joints and fixings for any room.

Tongue and Groove Calculator

Calculate tongue and groove boards for wall cladding, ceilings and floors.

Window Board Calculator

Calculate window board sizes, lengths and fixings for window reveals.

Staircase Material Calculator

Calculate treads, risers, stringers and timber for staircase construction.

Timber Cutting Optimiser

Optimise timber cutting from standard stock lengths to minimise waste.

Rafter Length Calculator

Calculate common, hip and valley rafter lengths with birdsmouth depth.

Cut Roof Framing Calculator

Calculate cut roof framing members including commons, hips, valleys and jack rafters.

Timber Frame Panel Calculator

Calculate timber frame panel studs, rails, bracing and sheathing sheets.

Kitchen Fitting Calculator

Calculate kitchen fitting materials including worktop, plinth, cornice and hardware.

Door Hanging Calculator

Calculate door hanging positions for hinges, latch, margins and fire door hardware.

Joist Notching and Drilling Calculator

Check permitted joist notching and drilling zones per Building Regulations.

Balustrade Calculator

Calculate balustrade balusters, handrail, newel posts and base rail.

Winder Staircase Calculator

Calculate winder staircase going at 270mm from narrow end for Part K compliance.

Roof Purlin Calculator

Size roof purlins from rafter load and span with strut positions.

First Fix Timber Calculator

Calculate first fix timber including wall plates, studs, noggins and joist hangers.

Built-In Wardrobe Calculator

Calculate built-in wardrobe carcass boards, rails, shelves and hardware.

Sash Window Repair Calculator

Calculate sash window repair materials including cords, weights and draught strips.

Timber Cladding Calculator

Calculate timber cladding boards by profile with battens and breather membrane.

Loft Hatch Calculator

Calculate loft hatch trimming timbers, fire-rated lining and insulation.

Window and Door Casing Calculator

Calculate window and door casing sets with architrave and fixings.

Structural Timber Connector Calculator

Select joist hangers, framing anchors and coach bolts for timber connections.

Drainage, sewage, attenuation and water management calculators for UK Building Regulations.

Manhole Calculator

Calculate manhole rings, benching, cover and frame for inspection chambers.

Land Drain Calculator

Calculate perforated pipe, gravel and geotextile for land drainage systems.

ACO Drain Calculator

Calculate channel drain lengths, end caps, outlets and gratings.

Sewage Treatment Plant Calculator

Size a sewage treatment plant by population equivalent per Building Regulations.

Septic Tank Sizing Calculator

Calculate septic tank capacity based on occupants and General Binding Rules.

Storm Water Attenuation Calculator

Size attenuation tanks and crates for storm water storage per Part H.

Percolation Test Calculator

Calculate percolation rate from field test data for soakaway and drainage field design.

Rainwater Downpipe Calculator

Calculate downpipe count from effective roof area and flow capacity by diameter.

Sewer Connection Calculator

Calculate sewer connection pipe length, bedding, inspection chambers and cover levels.

Pump Station Calculator

Size pump stations from inflow rate with chamber volume and rising main diameter.

Grey Water System Calculator

Calculate grey water recycling system storage tank, treatment unit and pump sizing.

Inspection Chamber Calculator

Calculate inspection chamber depth, risers, benching and cover class by traffic.

Soakaway Crate Calculator

Calculate soakaway crate volume, membrane wrap and pipe connections per BRE 365.

Pipe Bedding Calculator

Calculate pipe bedding depth, haunch and pea gravel volume by trench width.

Drainage Gradient Calculator

Calculate foul and surface water drainage gradients and invert levels per manhole.

Water Main Sizing Calculator

Size water mains from loading units, simultaneous demand and MDPE pipe selection.

Foul Drainage Layout Calculator

Calculate foul drainage pipe routing, minimum cover depths and inspection chamber positions.

Surface Water Drainage Calculator

Calculate surface water pipe capacity from impermeable area and rainfall intensity.

Drainage Connection Fee Calculator

Calculate water company sewer connection and build-over agreement fees.

Interceptor Trap Calculator

Size interceptor traps from flow rate and retention time with service requirements.

Perforated Pipe Calculator

Calculate drainage field perforated pipe length from percolation rate with trench spacing.

Rising Main Calculator

Size rising mains from flow rate and total pump head including friction losses.

Swale and Bioretention Calculator

Calculate SuDS swale and bioretention design storm volume with filter medium depth.

Loft boarding, conversion, ventilation and attic calculators for UK properties.

Loft Boarding Calculator

Calculate loft boards, battens and fixings for loft storage flooring.

Loft Ladder Sizing Calculator

Calculate loft ladder length and opening size for your floor-to-floor height.

Loft Conversion Head Height Calculator

Check if your loft has enough head height for a loft conversion.

Loft Load Capacity Calculator

Calculate safe storage load for loft joists based on size and spacing.

Loft Ventilation Calculator

Calculate eaves and ridge ventilation area to comply with BS 5250.

Dormer Sizing Calculator

Calculate dormer window dimensions, cheek cladding and structural opening size.

Loft Conversion Cost Estimator

Estimate loft conversion cost per m² by type: Velux, dormer, hip-to-gable or mansard.

Loft PD Volume Calculator

Calculate loft permitted development volume limits for terraced, semi and detached properties.

Loft Staircase Space Calculator

Calculate floor opening size and area lost for loft staircases by type.

Fire Escape Window Calculator

Check Part B fire escape window requirements for loft habitable rooms.

Loft Steel Beam Calculator

Calculate loft purlin or ridge beam size from rafter loads and span.

Loft Insulation Upgrade Calculator

Calculate loft conversion insulation to achieve U=0.15 with PIR and plasterboard.

Loft Floor Strengthening Calculator

Calculate additional joists for loft floor strengthening with strutting and boarding grade.

Hip-to-Gable Calculator

Calculate hip-to-gable conversion steelwork, gable wall and new roof tiles.

Mansard Loft Calculator

Calculate mansard loft conversion rear wall, cladding, insulation and structural steel.

Loft Party Wall Calculator

Calculate loft party wall Part E and fire-rated boarding with acoustic sealant.

Loft Bathroom Calculator

Calculate loft bathroom soil pipe routing, pump sizing and ventilation per Part F.

Loft Electrical Load Calculator

Calculate additional electrical circuits for loft conversion from consumer unit.

Damp proofing, timber treatment, mould removal and condensation calculators.

Timber Treatment Calculator

Calculate timber preservative and treatment quantities by surface area.

Woodworm Treatment Calculator

Calculate woodworm treatment spray and paste for infested timber.

Rising Damp Treatment Calculator

Calculate DPC injection cream, drill spacing and replastering for rising damp.

Condensation Risk Calculator

Calculate dew point and interstitial condensation risk for walls and roofs.

Mould Treatment Calculator

Calculate mould wash, steriliser and anti-mould paint for affected areas.

Dry Rot Treatment Calculator

Calculate dry rot treatment including cut-back, fungicide and replacement timber.

Basement Tanking Calculator

Calculate cementitious tanking slurry, corner fillets, membrane and sump pump requirements.

Cavity Drain Membrane Calculator

Calculate cavity drain membrane, plugs, floor channel and sump chamber quantities.

Sub-Floor Ventilation Calculator

Calculate airbrick count and ventilation area per metre of external wall.

Damp Survey Readings Calculator

Interpret damp meter readings by material type with acceptable WME thresholds.

Wet Rot Treatment Calculator

Calculate wet rot treatment with cut-back distance, hardener, filler and preservative.

Flood Damage Drying Calculator

Calculate flood damage drying rates, dehumidifier size and estimated weeks to dry.

Condensation Ventilation Calculator

Calculate ventilation rates to reduce RH below 65% with extract fan or PIV sizing.

PIV Unit Sizing Calculator

Size positive input ventilation units from house volume and air changes.

Salt Contamination Calculator

Calculate salt contamination plaster removal height and salt-resistant render specification.

External Waterproofing Calculator

Calculate external waterproofing excavation, membrane, protection board and drainage.

Calculate plasterboard sheets, joint tape, filler, screws and nogging for drylining walls and ceilings.

Building control fees, planning applications and UK Building Regulations compliance tools.

Building Control Fee Calculator

Estimate building control fees for UK domestic projects including plan check, inspection and VAT.

Part L Compliance Calculator

Check element U-values against Part L 2021 targets for walls, floors, roofs and windows.

Part B Fire Strategy Calculator

Calculate fire resistance periods, escape distances and compartment sizes per Part B.

Part E Sound Test Calculator

Check separating wall and floor dB targets and select systems to achieve Part E compliance.

Part F Ventilation Calculator

Calculate Part F ventilation system selection with extract rates and background ventilators.

Part G Water Efficiency Calculator

Calculate Part G 125 L/person/day water efficiency budget by fitting type.

Part H Drainage Compliance Calculator

Check Part H drainage pipe sizes, gradients, cover depths and inspection chambers.

Part K Stair Compliance Calculator

Check staircase rise, going, pitch, headroom and handrail against Part K limits.

Part M Access Calculator

Check Part M access requirements for thresholds, door widths, ramp gradients and turning circles.

Part P Electrical Notification Calculator

Determine Part P notification requirements by electrical work type.

CDM Compliance Calculator

Calculate CDM notification thresholds and duty holder identification.

Lawful Development Certificate Checker

Assess lawful development certificate requirements with 4-year and 10-year rules.

FENSA Registration Calculator

Calculate FENSA registration fees vs building control route for window installations.

Competent Person Scheme Calculator

Determine required competent person scheme by work type with cost comparison.

EPC Improvement Calculator

Calculate EPC rating improvement from ranked energy efficiency measures.

Window U-values, glazing units, sealants, bi-fold doors and glass calculators.

Window U-Value Calculator

Calculate window U-value from glass, frame and spacer thermal performance.

Double Glazing Unit Calculator

Calculate DGU thickness, weight per m² and thermal performance by gas fill.

Window Condensation Risk Calculator

Calculate window condensation risk from internal temperature, RH and dew point.

Sealant and Mastic Calculator

Calculate sealant cartridges from joint volume per window frame.

Window Security Spec Calculator

Determine PAS 24 window security requirements by floor and access level.

Secondary Glazing Calculator

Calculate secondary glazing panel area, frame length and U-value improvement.

Bi-Fold Door Calculator

Calculate bi-fold door structural opening, lintel size and leaf count.

Sliding Door Calculator

Calculate sliding door opening size, track length, structural header and drainage.

Trickle Vent Calculator

Calculate Part F trickle vent equivalent area per room with unit selection.

Roof Window Calculator

Select roof window size by room area for Part L daylight with flashing kit.

Skylight Calculator

Calculate skylight structural opening, kerb depth, upstand and drainage detail.

Bay Window Structural Calculator

Calculate bay window gallows brackets, foundation and roof covering area.

Juliet Balcony Calculator

Calculate Juliet balcony glass panel dimensions and fixing bolt requirements.

Glass Balustrade Calculator

Calculate glass balustrade panel dimensions, base channel and wind loading.

Curtain Walling Calculator

Calculate curtain walling mullion spacing, transom heights and glazing unit sizes.

Acoustic Glazing Calculator

Calculate acoustic glazing Rw rating by glass configuration and laminated options.

Window Replacement Calculator

Calculate window replacement quantities with frame material and U-value comparison.

French Door Calculator

Calculate French door opening width, lintel span and Part L U-value compliance.

Conservatory Glazing Calculator

Calculate conservatory glazing panels, ridge length, eaves beam and valley bars.

Window Board and Sill Calculator

Calculate internal window board and external sill dimensions with drip channel.

Structural Glass Beam Calculator

Calculate structural glass fin and beam sizing for frameless glazing systems.

Window Fire Escape Calculator

Check Part B fire escape window minimum dimensions and cill height requirements.

Fire doors, fire stopping, compartmentation, escape routes and Part B compliance calculators.

Fire Door Specification Calculator

Determine FD30/FD60 fire door specification with intumescent strip and hardware.

Fire Stopping Calculator

Calculate fire stopping materials by penetration type and wall/floor fire rating.

Fire Compartmentation Calculator

Calculate fire compartment maximum area and fire wall/door positions by building use.

Fire Escape Distance Calculator

Check maximum travel distances to fire exits by building type.

Fire Resistance Period Calculator

Determine fire resistance period from building height and purpose group per Table B3.

Fire Exit Width Calculator

Calculate fire exit width from occupancy numbers at 5mm per person.

Fire Damper Calculator

Calculate fire dampers at compartment duct penetrations with size matching.

Smoke Vent Calculator

Calculate AOV smoke vent size and free area for common stairs.

Passive Fire Protection Calculator

Calculate intumescent strips, cold smoke seals and door closer selection.

Fire Alarm Zone Calculator

Calculate BS 5839 fire alarm zones, detector count and sounder coverage.

Emergency Lighting Layout Calculator

Calculate BS 5266 emergency lighting spacing and battery duration.

Sprinkler System Calculator

Calculate BS 9251 residential sprinkler head count, pipe sizing and tank sizing.

Cavity Barrier Calculator

Calculate cavity barrier positions at party walls, 20m intervals and around openings.

External Wall Fire Rating Calculator

Determine external wall cladding requirements by building height.

HMO Fire Safety Calculator

Calculate HMO fire alarm grade, fire door locations and escape route widths.

Fire Mastic and Sealant Calculator

Calculate fire-rated mastic joint length and cartridge coverage per penetration.

Smoke Detector Layout Calculator

Calculate BS 5839-6 smoke detector grade, coverage area and ceiling height limits.

Fire Escape Signage Calculator

Calculate BS 5499 fire escape sign sizes from viewing distance and sign count.

Fire Risk Score Calculator

Calculate fire risk score from ignition sources, fuel load and detection quality.

External Fire Spread Calculator

Calculate unprotected area percentage by boundary distance per Approved Document B.

Loft Conversion Fire Safety Calculator

Calculate loft conversion fire safety requirements for protected stairway and alarms.

Commercial Fire Strategy Calculator

Calculate commercial fire strategy with travel distances, exit widths and sprinkler trade-offs.

Heat pump sizing, solar PV, battery storage, biomass and renewable energy calculators.

Air Source Heat Pump Sizing Calculator

Size air source heat pumps from whole house heat loss with defrost derating.

Ground Source Heat Pump Calculator

Calculate ground source heat pump borehole depth or trench pipe loops per kW.

Heat Pump COP Calculator

Calculate heat pump COP and seasonal COP with running cost comparison vs gas.

Heat Pump Radiator Calculator

Re-size radiators for heat pump 45C flow with de-rating factor.

Solar PV Array Calculator

Calculate solar PV array size, orientation yield factor and annual kWh by UK region.

Solar PV Inverter Calculator

Size solar PV inverters from array kWp with string voltage check.

Solar Thermal Calculator

Calculate solar thermal panel area, cylinder sizing and glycol volume.

Battery Storage ROI Calculator

Calculate battery storage return on investment from daily cycles and tariff differential.

BUS Grant Calculator

Check Boiler Upgrade Scheme grant eligibility and amounts for heat pumps and biomass.

Smart Export Guarantee Calculator

Calculate Smart Export Guarantee income from PV export kWh and SEG rate.

Heat Pump Buffer Tank Calculator

Calculate heat pump minimum system volume and buffer tank size to prevent short cycling.

UFH for Heat Pump Calculator

Calculate underfloor heating for heat pump at 35-45C flow temperature.

Hot Water Heat Pump Calculator

Size dedicated DHW heat pump from daily litres demand with cylinder pairing.

Heat Pump Noise Calculator

Calculate heat pump noise at boundary from source dB and distance.

Solar Panel Shading Calculator

Calculate solar panel shading loss from object height, distance and seasonal variation.

Heat Pump Pipework Calculator

Calculate heat pump pipework size from flow rate with glycol effect.

Hybrid Heat Pump Calculator

Calculate hybrid heat pump balance point temperature and annual cost comparison.

Biomass Boiler Calculator

Size biomass boilers from heat demand with fuel store and flue per Doc J.

Solar Panel Roof Area Calculator

Calculate usable solar panel roof area excluding dormers, vents and shading.

Renewable Energy Payback Calculator

Compare renewable energy options by installation cost, annual saving and payback period.

Wind Turbine Calculator

Calculate wind turbine annual kWh from mean wind speed and power curve.

EPC Improvement from Heat Pump Calculator

Estimate EPC rating improvement from replacing boiler with heat pump.

Heat Pump Cylinder Sizing Calculator

Size hot water cylinders for heat pump with larger coil surface area for low-temp flow.

Carbon Offset Calculator

Calculate annual CO2 savings from replacing gas boiler with heat pump.

MCS Design Compliance Calculator

Check MCS heat pump design compliance for heat loss, oversizing and noise.

Extract fans, ductwork, MVHR, air conditioning and ventilation calculators.

Extract Fan Sizing Calculator

Size extract fans per Part F rates with duct resistance calculation.

Ductwork Sizing Calculator

Size ductwork from flow rate and velocity with rectangular equivalent.

Duct Pressure Drop Calculator

Calculate duct system pressure drop from fittings and total system resistance.

Air Change Rate Calculator

Calculate required air changes per hour from room volume and use type.

MVHR Unit Sizing Calculator

Size MVHR units from total extract and supply rates with boost mode.

MEV System Calculator

Calculate centralised MEV fan duty, branch duct sizing and boost switching.

dMEV Fan Calculator

Size decentralised MEV fans per room with power consumption and SFP check.

Kitchen Cooker Hood Calculator

Calculate cooker hood extract rate with make-up air provision and duct to external.

Ventilation Background Rate Calculator

Calculate Part F whole dwelling ventilation rate with trickle vent EA per room.

Cooling Load Calculator

Calculate room cooling load from solar gain, internal gains and fabric gains.

Air Conditioning Sizing Calculator

Size air conditioning from room cooling load with pipe run and drain routing.

Heat Recovery Efficiency Calculator

Calculate MVHR heat recovery energy saved and net benefit vs running cost.

CO2 Monitoring Calculator

Calculate CO2 sensor placement and ventilation boost trigger levels.

Commercial Ventilation Calculator

Calculate commercial ventilation rates per CIBSE Guide B by room type.

Grille and Diffuser Sizing Calculator

Size grilles and diffusers from neck velocity, free area ratio and throw distance.

Condensation Prevention Calculator

Calculate condensation prevention from surface temperature, dew point and ventilation rate.

Laundry Room Ventilation Calculator

Calculate laundry room extract rate from moisture release with ductwork to external.

Server Room Cooling Calculator

Calculate server room cooling capacity from IT equipment heat output.

Specific Fan Power Calculator

Calculate specific fan power and check against Part F SFP limits.

Ventilation Commissioning Calculator

Calculate target vs measured ventilation flow rates for commissioning records.

Steel beams, columns, connections, balustrades and metalwork calculators.

Universal Beam Calculator

Calculate universal beam size from UDL, moment capacity and deflection check.

Steel Column Calculator

Calculate steel column size from axial load and effective length buckling check.

Steelwork Weight Calculator

Calculate steelwork total weight from section catalogue with connection allowance.

Base Plate Calculator

Calculate steel base plate area and thickness from column load and bearing pressure.

Steel Connection Bolt Calculator

Calculate steel connection bolt group capacity in shear and bearing.

Weld Capacity Calculator

Calculate fillet weld capacity from throat, length and steel grade.

Metal Balustrade Calculator

Calculate metal balustrade posts, handrail, infill bars and base plate fixings.

Steel Staircase Calculator

Calculate steel staircase stringer size, tread brackets and landing beam.

RSJ Installation Calculator

Calculate RSJ installation support sequence, bearing length and padstone.

Steel Lintel Calculator

Select Catnic or IG steel lintel from opening width with deflection check.

Purlins and Side Rails Calculator

Calculate purlin and side rail section size from rafter spacing and loading.

Metal Decking Calculator

Calculate metal decking profile, concrete topping, shear studs and mesh.

Structural Steel Painting Calculator

Calculate structural steel surface area and paint coverage per coat.

Fire Protection Steel Calculator

Calculate steel fire protection from Hp/A section factor by fire rating.

Steel Gate Calculator

Calculate steel gate frame section from weight and wind load with hinge sizing.

External Steel Staircase Calculator

Calculate external steel staircase per BS 5395 with galvanising area.

Scaffold hire, tower scaffolds, MEWP selection and working at height calculators.

Demolition waste, asbestos surveys, strip-out quantities and disposal calculators.

Basement conversion, waterproofing, underpinning and cellar calculators.

Extension costs, foundations, roofing, garage conversions and building project calculators.

Extension Cost Estimator

Estimate extension cost per m² for single and two storey with material breakdown.

Extension Foundation Calculator

Calculate extension foundation depth and width with tree proximity per NHBC Table 4.2.

Extension Roof Calculator

Calculate extension roof materials for pitched or flat with insulation.

Extension Wall Calculator

Calculate extension wall materials: blocks, insulation, bricks, DPC and wall ties.

Garage Conversion Calculator

Calculate garage conversion insulation, replacement door structure and services.

Extension Glazing Calculator

Calculate extension glazing area against Part L 25% maximum with U-value check.

Extension Heating Calculator

Calculate extension heating from room heat loss with radiator or UFH sizing.

Extension Electrical Calculator

Calculate extension electrical circuits, consumer unit ways and SWA for detached.

Extension Drainage Calculator

Calculate extension drainage connection, inspection chambers and build-over requirements.

Side Return Extension Calculator

Calculate side return extension steelwork, glazing and drainage re-route.

Extension Steel Beam Calculator

Calculate extension opening steel beam from tributary area loading.

Extension PD Checker

Check extension dimensions against permitted development depth, height and eaves limits.

Conservatory Base Calculator

Calculate conservatory base foundation, slab, DPM and dwarf wall.

Conservatory Roof Replacement Calculator

Calculate conservatory solid roof replacement structural upgrade and insulation.

Porch Calculator

Calculate porch materials with PD check for under/over 3m².

Orangery Calculator

Calculate orangery brick columns, lantern roof, glazing and structural beam.

Extension Party Wall Calculator

Determine extension party wall notice requirements from boundary distance.

Annexe Calculator

Calculate annexe self-contained requirements with utility connections.

Extension Slab Calculator

Calculate extension ground floor slab buildup: hardcore, DPM, insulation and concrete.

Extension Ventilation Calculator

Calculate extension Part F ventilation with trickle vents and extract in wet rooms.

Extension Fire Safety Calculator

Calculate two-storey extension fire safety: protected stairway, FD30 doors and alarms.

Flat Roof Extension Calculator

Calculate flat roof extension buildup with insulation, membrane, upstand and drainage.

Day rates, job pricing, tax, CIS, profit margins and business calculators for tradespeople.

Day Rate Calculator

Calculate net income from day rate after NI, income tax, pension and insurance.

Hourly Rate Calculator

Calculate hourly rate from target income, overheads, profit margin and billable hours.

Job Pricing Calculator

Calculate job price from materials, labour, waste, travel, markup and VAT.

Profit Margin vs Markup Calculator

Convert between profit margin and markup percentages with worked examples.

Mileage Cost Calculator

Calculate mileage costs at HMRC rates vs actual vehicle running costs.

Self Assessment Tax Calculator

Calculate self assessment income tax, NI Class 2 and Class 4 from trading profit.

VAT Threshold Calculator

Track rolling 12-month turnover against VAT threshold with flat rate comparison.

Tool Depreciation Calculator

Calculate tool Annual Investment Allowance tax saving and capital allowances.

Subcontractor CIS Calculator

Calculate CIS deductions at 20% or 30% with materials exemption.

Job Completion Time Calculator

Estimate job completion time from task database adjusted by scope.

Material Markup Calculator

Calculate material markup from trade price with VAT handling comparison.

Break-Even Calculator

Calculate break-even days per month from fixed costs and day rate.

Cash Flow Forecast Calculator

Calculate monthly cash flow from deposits, staged payments and overheads.

Quote Comparison Calculator

Compare supplier quotes normalised to per-unit delivered cost.

Payment Schedule Calculator

Calculate payment schedule with deposit and milestone-based staged payments.

Retention Calculator

Calculate contract retention at practical completion and defects period end.

Daywork Rate Calculator

Calculate RICS daywork rates for labour, materials and plant with percentages.

Plant Hire Cost Calculator

Calculate plant hire cost by machine type, period, delivery and operator.

Skip Hire Cost Calculator

Calculate skip hire cost by size with permit fee and recycling comparison.

Insurance Cost Calculator

Estimate annual trade insurance costs for public liability, employers and tools.

Scaffold Hire vs Buy Calculator

Calculate scaffold hire vs buy breakeven point with storage and inspection costs.

Project Profit Calculator

Calculate project profit from revenue minus all costs with margin percentage.

Manual handling, noise exposure, COSHH, CDM and construction health and safety calculators.

Embodied carbon, recycled materials, green roofs, Passivhaus and sustainable construction calculators.

Plain-English definitions of common UK building and trade terms.

What Is a Bonding Coat?

What bonding coat plaster is, when to use it, coverage rates and the difference between bonding and browning.

What Is BS 7671?

The UK standard for electrical installations explained, covering the 18th Edition wiring regulations and Part P compliance.

What Is a Cavity Wall?

How UK cavity wall construction works, the purpose of the cavity, insulation options and common problems.

What Is Dot and Dab?

How the dot and dab plasterboard fixing method works, when to use it, and adhesive quantities.

What Is Part L?

Part L of the UK Building Regulations explained, covering conservation of fuel and power requirements.

What Is Pointing?

Types of pointing in brickwork, repointing costs, mortar mixes and when to repoint.

What Is an R-Value?

How thermal resistance (R-value) works, how it relates to U-values and why it matters for UK building regulations.

What Is Screed?

Types of floor screed, thickness, drying times and when you need screed for UK floors.

What Is a Skim Coat?

How skim coat plaster is applied, coverage rates, thickness, drying time and when to skim coat walls.

What Is a U-Value?

How U-values are calculated, Part L targets and why they matter for insulation and energy efficiency.

What Is an RSJ?

What a rolled steel joist is, when RSJs are needed in UK construction, sizing and installation.

What Is a Soakaway?

How soakaways work, BRE 365 sizing, when they are required and installation guidance.

What Is Part P?

Part P electrical safety explained: notifiable work, competent person schemes and Building Control.

What Is a DPC?

Damp proof courses explained: types, installation heights, materials and when to replace.

What Is Part B?

Part B fire safety explained: fire resistance, escape routes, compartmentation and fire stopping.

What Is Airtightness?

Building airtightness explained: testing, Part L targets, common leakage paths and sealing methods.

What Is CIS?

Construction Industry Scheme explained: registration, deduction rates, verification and monthly returns.

What Is CDM?

Construction Design and Management regulations explained: duty holders, F10 notification and compliance.

What Is Tanking?

Basement and cellar tanking explained: Type A, B and C waterproofing systems and when to use each.

What Is a Party Wall?

Party Wall Act explained: notice requirements, 3m/6m rules, surveyors and awards.

What Is an EPC?

Energy Performance Certificates explained: ratings A-G, when needed, costs and improvement measures.

What Is MVHR?

Mechanical ventilation with heat recovery explained: how it works, efficiency, installation and Part F.

What Is a Thermal Bridge?

Thermal bridging explained: psi-values, common junctions, SAP impact and mitigation strategies.

What Is SAP?

Standard Assessment Procedure explained: what it measures, Part L compliance, ratings and calculations.

What Is Permitted Development?

Permitted development rights explained: extensions, outbuildings, limits and when planning permission is needed.

Useful reference guides, charts and tables for UK construction and trades.

Concrete Mix Ratios

Standard UK concrete mix ratios explained with quantities per cubic metre and guidance on when to use each.

Insulation U-Values

Part L target U-values for walls, floors, roofs and windows with insulation thicknesses to achieve compliance.

UK Brick Dimensions

Standard UK brick sizes, coordinating dimensions and bricks per square metre for common bond patterns.

UK Cable Sizes

BS 7671 cable sizes and current ratings for common UK domestic circuits and installations.

UK Plasterboard Sizes

All standard UK plasterboard sizes, thicknesses, weights and types including fire-rated and moisture-resistant boards.

UK Timber Sizes

Standard UK timber sizes in CLS and regularised with metric and imperial equivalents.

UK Pipe Sizes

Standard UK plumbing and heating pipe sizes in copper, plastic and steel.

UK Screw and Fixing Sizes

UK screw gauge sizes, lengths and pilot hole diameters for wood, masonry and metal fixings.

UK Block Sizes

Standard UK concrete block sizes, weights and blocks per m² by type.

Part L 2021 U-Value Targets

Part L 2021 target U-values for all building elements with notional dwelling values.

BS 7671 Domestic Circuit Guide

BS 7671 domestic circuit specifications: cable sizes, MCB ratings and protective devices.

Mortar Mix Ratios

Standard mortar mix ratios for bricklaying, blockwork, rendering and pointing.

Radiator BTU Output Table

Radiator BTU output reference by size and type for heating system design.

Roof Tile Coverage Rates

Roof tile coverage rates per m² by tile type with batten gauge.

Paint Coverage Rates

Paint coverage rates in m² per litre by paint type and surface.

Skip Size Guide

Skip sizes from mini to RoRo with volume, weight limits and typical uses.

Drainage Pipe Sizes and Falls

Drainage pipe sizes and minimum fall gradients for foul and surface water.

Fixings Guide by Wall Type

Fixing types and pull-out loads by wall material: brick, block, plasterboard, timber and concrete.

Why Use TradeCalculator?

Every calculator on this page is completely free, requires no signup, and works on any device. All tools use UK metric measurements, standard UK product sizes, and reference current UK building regulations where applicable.

Whether you're pricing a job, ordering materials, or checking compliance, TradeCalculator helps you get accurate estimates quickly. Results include wastage allowances and let you input your own material prices for cost estimates tailored to your suppliers.