Sound Insulation for Floors

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Acoustic Insulation: what is a Separation Layer? 

Separation layers, or separating floors, are built between joined properties, normally or domestic residences. As we’ve mentioned, they can be found between commercial properties too, such as a flat above a shop for example. The job of a separating floor is to act as soundproofing to limit noises from neighbours. These floors also come under party structures.

What’s a party structure?

Party structures are used in flats, semi-detached houses and maisonettes. This includes floors, as well as shared property boundaries. These boundaries can also include garden walls, but not wooden fencing. Walls built on land shared by two or more owners are also considered party structures, and can incorporate sound insulation. 

What are the different types of separating floors?

There are four specific types of separating floors that are listed in government guidance for acoustic insulation. This guidance is listed under Approved Document E. So when we talk about separating floors, these can also include the ceilings of the rooms below. 

What type of acoustic insulation do you need for floors?

Much like other forms of insulation, like thermal loft insulation, there are different kinds of insulation for soundproofing floors. The main type of sound insulation you’ll find is mineral wool, which comes in rolls, slabs and panels. This acoustic insulation is more commonly known as rockwool, which is highly effective for soundproofing both floors and walls and often used for timber joist flooring.

Do you need acoustic insulation?

There will always be some kind of noise from neighbours, from unexpected DIY to parties that go on into the night. Unfortunately it’s not always possible to limit this kind of noise, but we can reduce the levels of other ambient sound from households above and below. These fall into two categories:

• Airborne noise – this covers sounds of the TV, music and conversation that come through walls through the air

• Impact noise – this causes vibrations that can be quite jarring, caused by footsteps, children playing or something heavy being dropped, for example.

Is soundproofing a legal requirement?

While it’s not necessary to add sound insulation between the floors of a single household (like the first floor of a house for one family), any floors between different residences do need to have soundproofing. This is detailed in the Approved Document, or Part E, of building regulations mentioned previously. 

This regulation was introduced in July 2003 and can cover public buildings as well as private dwellings such as flats and maisonettes built after this time. While some buildings finished before 2003 might not have soundproofing installed, it’s possible to have an evaluation on whether or not it’s worthwhile getting this done. However, costs and practicality might be an issue. 

For more on home improvements, including advice on insulation such as soundproofing a loft, we have further guidance to help with your projects.

Disclaimer: The information contained on this page is intended as an overall introduction and is not intended as specific advice from a qualified professional. Travis Perkins aims to avoid, but accepts no liability, in the case that any information stated is out of date.