Soundproofing between floors

pancaz

Hi
Have always lived in a bungalow which we are now converting into a double storey house (family growing and need more rooms). I am worried about the annoying sound coming from the first floor (when someone is walking or kids stomping) and wondering if I could do something to soundproof between the floors. We will have laminate flooring on the 1st floor. 

Thanks in advance.

FreeBear

Carpet with a decent underlay would help. That would be the quick & cheap fix to reduce some of the noise.

More expensive measures would be to add sound absorbing insulation under the floor and isolating the ceiling from the joists above. There are sound insulating systems that consist of various materials bonded to chipboard/plywood designed to drop in to standard spaced joists - No idea how effective they are, or what sort of cost. Unfortunately, cutting down on noise transmission is complex and is something that really needs to be designed in at the drawing board stage.

macman

Laminate flooring is probably the worst choice you can make in this situation. Presumably these will be bedrooms, so why laminate?

Davesnave

As above, you may have left it late in the day to design in features to specifically suppress noise from above, but avoiding laminate and similar hard flooring in rooms other than bathrooms will avoid creating more of it.

daivid

I put sound insulation between the living room and bedrooms above. I used 50mm acoustic slab, it has reduced the transmission of sound and the living room heats faster in winter. As is cautioned above the effectiveness is reduced when acoustic insulation is retro fitted, disturbing floorboards reduces their sound insulating properties, particularly with tongue and groove. So unless you need to lift/replace floorboards anyway I would would just go with good quality underlay and carpet upstairs.

Mutton_Geoff

daivid said:

disturbing floorboards reduces their sound insulating properties, particularly with tongue and groove

I've never heard that before. In fact lifting nailed down boards then refitting them with screws usually stops any squeaks that existed before.

daivid

I would agree on the squeaks, a friend uses gripfill along with the screws, some may say that is a step to far...

I've got no science to back it up but it made sense to me that if the tongues are broken in places it will reduce the integrity of the barrier and allow more sound through. This would not impact on the percussive transmission though clearly. If you are going to replace any damaged boards then this wouldn't be a (potential) issue.

Norman_Castle

daivid said:

I put sound insulation between the living room and bedrooms above. I used 50mm acoustic slab, it has reduced the transmission of sound and the living room heats faster in winter.

Were you trying to avoid the sound going up or down? How effective was it on the sound of voices or television going up into the bedrooms? Are the bedrooms now colder?

daivid

Norman_Castle said:

Were you trying to avoid the sound going up or down? How effective was it on the sound of voices or television going up into the bedrooms? Are the bedrooms now colder?

Predominantly to reduce sound going up. I am happy with the results: if both doors (bedroom & living room) are open you can hear the TV clearly in the bedrooms or someone on the phone upstairs in the living room, close one door and its pretty muffled, close both and it's pretty much gone totally - in one room there was an edge I couldn't get the slab into if you're directly above this you can still hear the tv. I didn't really live without the insulation very long, and I did it as much to make things better at no great cost (at the same time as other renovations) rather than out of need to suppress noise that was driving me mad.

The bedrooms are not cold but they weren't ever a problem (after putting loft insulation in a few weeks after buying): the radiators in the bedrooms are much better matched to the room sizes. The single radiator in the living room is perhaps slightly small for the room and is along one long wall to about 1/2 way. Heating the far end didn't seem to happen for hours prior to the acoustic slab between floors, generally the whole room now warms quickly after turning the heating on.

DevilDamo

As @FreeBear mentioned, you’d need to create something more along the lines of a floating floor, which is achieved via some kind of resilient/isolation/acoustic tape or strips between the joists and floor deck. That will help with impact sound and then having 100mm mineral wool or similar between the joists that will help with airborne sound.