There are two main types of noise to suppress: impact noise reduction and airborne noise reduction.
Impact noise reduction is where the thickness and sponginess of the underlay stops the sound of footfall on the floor. This is much easier with a carpet underlay as carpet underlays are thicker anyway and the carpet also helps. This type of noise suppression is especially important in upstairs rooms or flats above the ground floor where the people below don’t want to hear the sound of people moving around upstairs.
Laminate or wood acoustic underlay makes a big difference to impact noise reduction. Without an underlay it’s just a solid wooden floor, so every footfall sounds like knuckles knocking on wood. The acoustic underlay adds a spongy layer which absorbs some of the noise of footfall. The often quite harsh, reverberating sound is softened by acoustic underlay especially, under wood or laminate underlay
Airborne noise reduction is the suppression of sound between floors. Any noise, such as conversation or the sound of the TV, is reduced or suppressed. The main things that make a difference here are the thickness and density of the materials used in the floor, so a thick high-density underlay works best. The best underlay in our range for noise suppression of this type is Tredaire Colours Red.
Not directly. Although an acoustic carpet underlay will provide a boost to your noise levels it will have other significant negative implications.
If you have a serious problem, such as a concern about the neighbour below your flat, then a high density carpet underlay such as Tredaire or System 10 might be the best solution. However, if you were to lay laminate or wood on top of a carpet underlay then the softness of the underlay would allow the laminate or wood to flex as you walked across it, which would damage the floor.
If you need this level of noise suppression then the solution is to put acoustic carpet underlay down and then to put a sub-floor layer above that, such as a couple of layers of plywood laid in opposite directions so there are no gaps. This will spread the load and stop any flex.
Part E building regulations define the maximum amount of noise transmitted between rooms.
Normally the underlay is not considered part of the fabric of the building, and so it makes no difference to whether the room meets Part E or not. After all, the acoustic underlay can be taken up if the flooring is changed. So, to meet the regs, anything has to be permanent.
Nevertheless, some landlords or builders specify that the underlay (whether it is acoustic underlay or not) must help to meet the regs. In cases such as this the best route is to use Colours Red if laying a carpet, or to use a crumb rubber underlay such as Tredaire or System 10 and then to put some layers of plywood on top of the underlay if laying a laminate or wood floor. Acoustic underlay is naturally very helpful in this process especially if it has high noise suppression values.