In this guide
When does Part E apply?
- New homes: houses and flats built from scratch.
- Material change of use: for example converting a house into flats, a barn or commercial building into a home, or creating rooms for residential purposes such as student rooms.
- Rooms for residential purposes: such as hostels, care homes and similar.
Part E doesn't normally apply if you're simply improving the soundproofing of your own existing home, for example lining a party wall. That's a voluntary upgrade and you can choose whatever level of performance you want.
The numbers for walls and floors between homes
| Element | New build | Conversion (material change of use) |
|---|---|---|
| Separating walls: airborne, DnT,w + Ctr | at least 45 dB | at least 43 dB |
| Separating floors and stairs: airborne, DnT,w + Ctr | at least 45 dB | at least 43 dB |
| Separating floors and stairs: impact, L'nT,w | no more than 62 dB | no more than 64 dB |
DnT,w + Ctr is a measure of how well a wall or floor blocks airborne sound like voices and music, with an adjustment (Ctr) that gives more weight to low-frequency sound. L'nT,w measures how much impact sound (footsteps) comes through a floor, so lower is better.
Internal walls and floors
Requirement E2 also covers walls and floors inside a new home or a home formed by conversion. Walls between a bedroom or a room with a WC and other rooms, and internal floors, need a laboratory sound reduction of at least Rw 40 dB. Walls containing a door and en-suite walls are exempt, and existing floors in a conversion aren't caught by this part.
Sound testing
To show compliance, separating walls and floors are usually sound tested on site before completion by an accredited tester, and the results go to Building Control. New-build developers can avoid testing by building to registered Robust Details, but those aren't available for conversions. In practice, conversions are normally tested, so it pays to get the construction right first time.
How we help
We build acoustic walls, floors and ceilings for conversions across Devon, working to your architect's or building control's specification and paying close attention to the details that decide a sound test. If you're early in a project, we can look at the existing structure and suggest a realistic build-up before the drawings are finalised.
Common questions
Does my extension need to meet Part E?+
Part E is aimed at new homes, conversions and rooms for residential purposes. An ordinary extension to your own house doesn't normally trigger the separating wall and floor requirements. Your building control officer can confirm for your project.
What happens if a sound test fails?+
Building Control won't sign the work off until it complies. That usually means remedial work, such as additional linings or ceilings, and a re-test, which is why getting the details right first time matters.
Who can carry out a Part E sound test?+
An accredited testing body, for example one that's UKAS-accredited or a member of the Association of Noise Consultants' registration scheme.
Free site survey
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We'll visit, find where the noise is getting in and give you a clear written quote. No obligation, and we cover all of Devon from Exmouth.