Underfloor Sound proofing!

Soldato
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Ok, so not the most exciting thread here but I can rely on getting good results when posting here and didn't know who else to ask. :D

We have a flat we are renovating and part of that is making the floors sound proof. Due to it being a *very* old building you can hear when the old lady below farts.

So, we are looking at Rockwool insulation but want to know if anyone knows of any alternatives? Long shot I know but thanks if you know any solutions or have any pointers! :)
 
lol, cheers dirtydog. Funnily enough I had done several searches but was trying to be too clever with my keywords etc and just got lots of company website trying to sell me stuff.

Seems your simple keywords did the trick. ;)
 
You won't be able to make a massive difference without replacing the ceiling below. In essence you need to introduce an isolation and absorbing quality to the floor.

Assuming you have timber floors your idea of Rockwool between the joists is a very good starting point and the more you can put in the better, at least 100mm thickness laid on top of the ceiling below between the joists. You can buy soundproofing mats that can be laid on top of the existing boards, then an isolation mat and finish off the floor with new boarding but obviously that will raise the floor level and also requires and acoustic sealant around the floor perimeter. Similar solutions are required for concrete floors. Talk to your local building control department and they will probably be able to give you a specification or at least point you in the right direction.

As a very minimum, use the Rockwool and then install rubber 'resiliant' strips along the joists before laying new boarding.
 
Yeah I don't know what the best or most effective solutions are, but I know there are several sites offering such products because I have looked into it myself in the past :)

The place you would get the most informed advice and opinions would be the 'neighbours from hell' website at http://nfh.org.uk :)
 
My uncle has a sound proof recording studio and he said it was a layer of egg cartons, I have heard it before, but I think he may have been joking.

Floor insulation seems the most (cost) effective way to go - Plus it would cost less to heat as well methinks.
 
dirtydog said:
Even though heat rises? ;)

Ah ha! it's you again

Yes, otherwise all I would have to do would be cut the top off my pc case and i wouldnt have to worry about the bottom half of the pc overheating - or better yet, with passive cooling you don't even need a fan to blow air onto the heatsink.

Anyway, every little helps?
 
SGCWill said:
My uncle has a sound proof recording studio and he said it was a layer of egg cartons, I have heard it before, but I think he may have been joking.
Not so, it is very common - as is carpet draped on the walls. The egg boxes are not so much for sound insulation as to prevent "standing waves".

To be honest, what really determines the most effective form of sound-proofing is the type of noise you are suffering from - e.g. Drum & Bass would be a complete nightmare. Density and isolation are what usually work best - just not very easy to achieve as a retro-fit in a domestic environment.

Following repeated visits from the council, my next door neighbour built an "inner room" out of celcon blocks in his garage to practice on his drum kit - it works great except when he leaves the air-lock door open to keep cool ;)
 
you will need to use different materials for the different ranges of sound. so rockwall between the joists will help reduce the noise between the joist but sounds will still travel down the physical joist, hence the need for a material to cover the existing floorboards, floor matting will also reduce a different frequency range. You need to make sure the joints in the matting dont coincide with the floor joints, seal the edges to each other and walls and then top off with flooringboard and the carpet/laminate as normal.
 
Shackley said:
Following repeated visits from the council, my next door neighbour built an "inner room" out of celcon blocks in his garage to practice on his drum kit

Box-in-a-box! That's the only fail safe solution ;)
 
What sort of sounds are you trying to prevent from passing through your floor?

I have just spent £2500 on my bedroom ceiling and after taking my upstairs neighbours to court (later this year) I will try and get some work done on their floors. I have spent a lot of time researching into sound proofing, so can give you some nice links.

Your building control will not know much about sound proofing as they tend to stick to the building regulations, which imo dont go far enough.

Keep in mind that the further you go, the more you will require the use of specialist materials to get the job done. And its the specialist items that you have to source from specialists that costs a lot.

Also what type of floor do you intend to have - laminate floors or carpet? Carpet with a nice thick underlay is excellent for dealing with impact noise.

Rockwool should form the basis for your insulation. I used 130mm thick 100kg/cubic metre blocks, as well as 50mm thick 140kg/cubic metre blocks.

In fact here is a thread that I made to explain what I did to my bedroom. More has been done since then and work will be done to the floor above my ceiling.
http://www.avforums.com/forums/showthread.php?t=396825
 
Mint_Sauce said:
We have a flat we are renovating and part of that is making the floors sound proof. Due to it being a *very* old building you can hear when the old lady below farts.

Is that when she takes the meat out.


Come on, i meant when she bends over to take the meat out of the freezer, what else did you think i meant. :D
 
sunama said:
:) Very interesting article you've done there, i may just use a few ideas for soundproofing my bedroom. My bedroom is above the living room and my sister works nights so i am kept up late every night at the moment. Ive told her to be quiet but the sound insulation is so poor you can hear quiet talking like they are in the room with me. Especially my brothers voice as it is deep.

My sound proofing thus far has been to block a hole in the plasterboard where the old fire alarm was :D . Looks like ill have to take up the floor boards and install some rockwool.
 
If you want to block out voices then rockwool is a great product to use - the thicker the better. If you want to take it a step further then add carpets (bog standard carpets are excellent at muffling sounds). Under the carpets you can put many different products - the best would be to use a rubber-type membrane that you can buy. This is placed underneath the underlay.

The real fun begins when you want to work with the ceiling. How about 3 layers of 12.5mm thick plasterboard? Greenglue is an interesting product that should be looked at if music/tv noise is a problem.
 
Thanks for everyones info, clears a lot up for us. Not sure why she farts, don't really want to think about it too much now after certain comments.. :D

The place is old, really old. It was a monastry at one point and has been converted to flats. The walls are really thick but the floor just doesn't block any sound. In our flat there's wood flooring, tung and groove which probably won't slot back in after taking it up...

So, we are stuck - something has to be done about the sound as it's so bad and the lady not only farts but we can hear her talking to herself and her crazy wonky eyed dog.

We are considering upping the floor, putting down rockwool and then trying to refit the old floor or failing that, get a new one. Or, maybe create a fake floor and raise the entire flat by a few inches (luckily the ceilings are very high so this isn't really a problem).

just about to check out sunama's thread now.
 
If you dont mind having carpets, you can simply lay down a layer of sound blocking membrane (about 5mm thick), then lay down a thick underlay, then a thick carpet.

If you are happy to raise the floor level a bit, then on top of your existing floor you could add a few layers of thick baseboard, on top of which you lay down your membrane, underlay and carpet.

For best results you need to take up the existing floor and fill the cavity with rockwool. Then throw out that cheapo tongue and groove flooring and put in real oak floorboads.

There are lots of different things you could do, depending on what your budget allows you to do.
 
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