Soundproofing celing

Hi all, first of all apologies if this is in the wrong forum. I am after some advice for some work I am looking to do with my 5 year old flat.

I am looking to remove the ceilings from my flat, install soundproof wool, fit resilient bars and put up a new ceiling. I wouldn't know how to rate my DIY abilites to be honest, but this job doesn't daunt me since the worst part is apparently the mess involved (there is a chance I am being naive!)

I have done some initial investigation into the current ceiling, looking through the light fitment holes it appears between the joists is hollow (no padded insulation??) and it's just rather flimsy board screwed to the joists. This does concern me as this is a ground-floor flat... how in gods name would that have passed soundproofing (or heat insulation) regs?

I have read around that the sound insulation properties of acoustic plasterboard is not that much better than normal, yet the former is a lot heavier... I would obviously prefer the lighter cheaper stuff considering most of the sound blocking is coming from wool and resilient bars.

Does anyone have an experience or advice at all? has anyone worked on new builds in the last few years that can confirm my suspicions about the existing ceiling? surely it cant just be a single board screwed to hollow joists??

So what kind of floor is above the joists ? Wood ? Concrete ?

Sound-reduction ( better not think of sound-proofing, you may be disappointed ) is not easy and major improvement is difficult without using lots of mass or space.

What kind of noise are you suffering from ?\

surely it cant just be a single board screwed to hollow joists??

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Well some builders do cut corners, but I hope not many are using hollow joists

I have not actually pulled any of the ceiling down yet to ascertain what is above the joists, I would assume wood? would it change the approach if it was concrete?

Is there an easy way to find out for sure? I was thinking of pulling down the small area of ceiling in the airing cupboard to have a proper inspection with minimal aesthetic impact.

Ah yes I appreciate it will be an exercise in reduction, the main issue is footfall noise. Voices, cupboard doors slamming etc are audible but muffled and not an issue if I have my TV on etc. There was also stereo noise but that was swiftly dealt with

Haha sorry, I meant hollow between the joists!

Never assume that the existing work has been carried out to regs, or inspected as such.

If the floorboards above are old and gappy, you could cut strips of plasterboard and push up flush against them, held in place with nails into the joist or small strips of wood. (don't fix into the floorboards themselves)
You can get acoustic and fire rated downlighters. But a better option would be to get a standard ceiling light or spot bar, holes in ceilings between dwellings is just wrong IMO.
Plenty of rockwool slab in the void (watch out for cables and electrical junctions) resibar and a double layer of standard 12.5mm pb should do a decent job. Stagger board joins, acoustic sealant the perimeter.

Footfall usually indicates a laminate or other hard floor above, not a lot you can do about this unless you are on really friendly terms with the upstairs lot (maybe offer to buy them a rug?)

Thanks Deluks, reassuringly everything you mention is along the lines of what I have planned.

Good shout about the downlighters, there are 4 in the kitchen area but would rather a spot bar to reduce holes... unless that requires a different circuit? don't want to touch electrics!

To be fair the sound from above is a whole range of general living noises so my focus is more towards the shoddy quality of the build rather than the guy above who is generally quite courteous. Having said that, I have investigated the rules on laminate above etc with the management company and they are in my favor, but making enemies will be my last resort

Having said that, I have investigated the rules on laminate above etc with the management company and they are in my favor, but making enemies will be my last resort

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Well I understand the problem and it is up to you. Impact noise will be the most difficult to minimise anyway so reducing other general noise will serve to emphasise it/

SimonPG said:

Does anyone have an experience or advice at all? has anyone worked on new builds in the last few years that can confirm my suspicions about the existing ceiling? surely it cant just be a single board screwed to hollow joists??

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I have just done this job in my flat.

Ceiling down, 150mm acoustic rockwool, res bars screwed to joists, 1 layer of 15mm soundbloc, then a layer of GreenGlue, then another layer of 15mm soundbloc plasterboard. I then sealed all around the perimeter with acoustic sealant.
Got it skimmed last month and have just finished painting.
The flat is sooooo much quieter..

Well chuffed.

It's interesting to hear an "after" report from someone who has done it . Out of interest, what did it end up costing ( materials ) per ft or m2 ?

For a 4.5m x 4.5m room, the materials cost £550.
Add on the plasterboard lift hire and sundries.
I did all the labour bar the plastering.

I did get a quote from a builder to do the whole job and he wanted £1600.

Ionkontrol said:

For a 4.5m x 4.5m room, the materials cost £550.
Add on the plasterboard lift hire and sundries.
I did all the labour bar the plastering.

I did get a quote from a builder to do the whole job and he wanted £1600.

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Good to hear reports of success from someone who is not a fake website testimonial or trying to sell me something!!

Due to time I have still not started this, but when I do I will try and document it with photos etc for anyone that is interested.

Simon, here are some photos I took during.....


Celing down, nice filthy job



Pathetic previous insulation (remember this is between two flats....




Rockwool going in....



Res bars up....



1st board of 1st layer going up. You will need a hoist as the boards are 45kg each.




False chimney for TV



Plasetered and painted

So it turns out I dont have wood joists etc above me, I am under concrete slabs with a hung metal frame. Below is a 4 way photo taken from the centre of the flat. Basically I have 1 large open cavity across the whole of my flat about 15cm deep.

That changes the plan a bit, obviously first purchase is rockwool, however now I need to be a lot more careful bringing down the existing ceiling as I want to keep that frame in tact.

Ionkontrol you have handled soundproof board, do you reckon this set up would handle the weight as well as proper joists would?? I can see by the colour (and the flakiness) that this is standard plasterboard here, but there may be a reason.

I genuinely think that rockwool alone is going to have a big affect here as currently sound is allowed to travel from one corner of the flat to the other with no obstruction at all, surely this is acting like one big speaker!?!

any thoughts/advice at this point???