How to add sound insulation in a ceiling?

[Russ42]

We have been desperately trying to reduce the noise in a bedroom from people weeing into the toilet above. We are reticent to put a sign on the toilet asking people to wee quietly. So far we have:

1. Boxed the plumbing up with insulation around the pipes

2. replaced the toilet with a more modern "back to the wall" toilet

3. Put a hole in the boxing and re-insulated with self adhesive foam from Bunnings

4. re-insulated the box with acoustic insulation from Bunnings.

My last ditch attempt ( before replacing the toilet with one with the cistern behind the wall which I think is not going to be good enough either) is to add a layer of material over the box. I am thinking of Gyproc Soundchek. We have guests arriving on Thursday and need to get the ceiling looking acceptible by then. Is this Gyproc the best solution or is there a better one. 1 sheet of the Soundchek will do a double layer, is this worthwhile or just over the top?

[JacobZ]

Hi @Russ42,

Do you have any photos of the area in question? I have an idea of what you are talking about, but it is hard to picture exactly what you mean.

It sounds like you’ve already gone to great lengths to deal with the toilet noise, and honestly, you’ve done most of the right things. What you’re dealing with now is one of the trickiest types of household noise: water hitting water. That sharp, echoey sound is surprisingly hard to block, especially when it’s coming through ceiling cavities and pipes.

At this point, adding a solid outer layer like Gyprock Soundchek makes a lot of sense. It’s a denser plasterboard made specifically to reduce sound, and it works well when combined with insulation. By adding more mass, you’re helping block the airborne noise that’s managing to escape the box. 

A double layer is definitely worthwhile. It adds more weight, which helps reduce how much sound gets through.

Outside of this, I would have to see what you are dealing with to offer any further advice.

Allow me to tag @Dave-1, @Noyade and @Nailbag to see what they think.

Jacob

[Russ42]

Thanks Jacob.... Love it when someone agrees with me..... Am off to Bunnings now. Will post any discoveries I have

[Dave-1]

Afternoon @Russ42 

Mmm from your descriptions I think you have run through the same ideas we will have, A few photos might help with some dofferent solutions. I wonder if you put in some heavy in thickness bathroom mats? Something that stops the whole bathroom above from doing that very apt description @JacobZ has described As 70's as it might seem having sound absorbing material may help out. Tho you have mntioned the pipes underneath.. mmmm I have those very exposed pipes at work and I have thought of nothing that can cover the sound. 

Will wait for some pics of what you have tried.

Dave

[Nailbag]

Hi @Russ42 

On top of the excellent advice by @JacobZ, I would also add filling every possible void with this sound deadening insulation. It's what used in home theatre walls. And what would make a substantial difference is to ask guests to pee to the side of the bowl if possible in lieu of the water as this will be significantly quieter

Nailbag

[Russ42]

Thanks Nailbag: I will try asking guests to fill every possible void with sound deadening insulation but asking them to pee on the side of the bowel may be a bit too hard for them......🤣 Oh, on the sensible side of things, I am thinking of putting fire retardant plaster board on the outside of the box. It is 16mm thick. I am checking if the insulation properties are superior to sound insulation but the weight may be too much (40kg approx) but the sound insulation is 13mm but only slightly lighter.

[EricL]

Hello @Russ42 

Please keep us updated with your progress, we look forward to seeing if the Gyprock Soundchek has helped with the sound insulation.

Eric