What are the Part E sound insulation requirements in the UK?

UK Building Regulations Approved Document E sets minimum sound insulation standards between dwellings. For walls separating dwellings, the minimum airborne sound insulation is 45 dB DnT,w + Ctr. For floors separating dwellings, the minimum airborne insulation is 45 dB DnT,w + Ctr and the maximum impact sound is 62 dB L'nT,w. New-build properties must also pass pre-completion testing.

What is the difference between resilient bars and soundbreaker bars?

Resilient bars (such as Gypframe RB1) are thin metal channels fixed across studs or joists at 600mm centres to decouple the plasterboard from the structure, reducing sound transmission. Soundbreaker bars (such as Mute Soundbreaker bars) provide a deeper isolation channel with better acoustic decoupling. Soundbreaker bars typically achieve 5-8 dB better performance than standard resilient bars, which can be the difference between passing and failing Part E.

How thick should acoustic mineral wool be for sound insulation?

For stud walls between dwellings, 100mm thick acoustic mineral wool (density 45 kg/m³ minimum, such as Rockwool RWA45 or Knauf Acoustic Slab) is recommended to fill the cavity completely. For timber floor/ceiling constructions, 100mm is also standard between joists. Enhanced systems may use higher-density products (60-80 kg/m³) for better low-frequency performance.

Do I need acoustic plasterboard or can I use standard plasterboard?

Acoustic plasterboard (such as British Gypsum Gyproc SoundBloc or Siniat Silent Board) is denser than standard plasterboard, typically 12.5mm thick at around 10-12 kg/m² compared to 8-9 kg/m² for standard board. For Part E compliance, acoustic plasterboard is recommended. For enhanced performance, two layers of acoustic plasterboard with staggered joints provides significantly better results.

Why is acoustic sealant important for sound insulation?

Sound travels through the weakest point in any construction. Even small gaps around the perimeter of a wall or floor can dramatically reduce the overall sound insulation. Acoustic sealant (such as Soudal Acoustic Sealant) fills these gaps and remains flexible, maintaining the acoustic seal as the building moves. It should be applied around all perimeter edges, at board joints, and around any service penetrations.

Sound Insulation Calculator — Acoustic Materials for Part E

Calculate acoustic insulation, resilient bars, acoustic plasterboard and sealant needed for walls and floors to comply with UK Building Regulations Part E.

Area & Construction

Wall or Floor Area

Total area to be sound-insulated

Perimeter Length (optional)

For sealant calculation. Leave blank to auto-estimate.

Construction Type

Part E airborne target: 45 dB

Target Performance

Enhanced uses 2 layers of acoustic plasterboard

Material Selection

Insulation Material

Acoustic mineral wool is the most common choice

Include soundbreaker bars

Better decoupling than resilient bars — recommended for enhanced performance

Include wastage allowance

Adds 10% extra for cutting and fitting

Wastage Percentage

10% is standard for acoustic insulation work

How We Calculate This

This calculator estimates the acoustic insulation materials required for walls and floors to meet or exceed UK Building Regulations Part E. It accounts for the construction type, target performance level, and chosen insulation material.

How it calculates

Insulation batts: Area ÷ 0.72 m² per batt (1200×600mm standard), rounded up to whole batts and grouped into packs.

Resilient bars: Installed at 600mm centres across the full area. Total linear metres = Area ÷ 0.6m, then divided by 3m bar length.

Acoustic plasterboard: Standard sheets are 2400×1200mm (2.88 m²). Enhanced performance uses two staggered layers, doubling the sheet count.

Acoustic sealant: Applied around the full perimeter plus at board joints. Each 310ml tube covers approximately 6 linear metres.

Part E performance targets

Walls between dwellings: Minimum 45 dB DnT,w + Ctr (airborne sound)
Floors between dwellings: Minimum 45 dB DnT,w + Ctr (airborne) and maximum 62 dB L’nT,w (impact sound)
Enhanced performance: Exceeds Part E by at least 5 dB — uses double-layer acoustic plasterboard and optionally soundbreaker bars

For best results, combine acoustic mineral wool insulation with resilient or soundbreaker bars and acoustic plasterboard. Seal all edges and penetrations with acoustic sealant to prevent flanking sound paths.

Frequently Asked Questions

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Last updated: February 2026

All calculations are estimates. Verify with your supplier.