Fixing resilient bars to joists

[endecotp]

Dear Experts,

I'm about to start my first resilient bar ceiling. The existing ceiling is old plasterboard nailed to joists; I'm going to fix resilient bars to that, screwed through into the joists, and then fix two layers of plasterboard.

What sort of screws should I be using to secure the resilient bars into the joists? A bit of Googling suggests that I should just be using regular plasterboard screws of suitable length - I have some 55mm ones - but that seems a bit lightweight to me. I think there will be about 5kg hanging from each screw. What would you use?

Any other tips?

Thanks, Phil.

 

[Fred61]

Hi I first must ask why ?? That’s why are you wanting this type of ceiling. We have only fitted this stuff in noise sensitive commercial applications in the past. So it seams a bit ott for a diy help question. Chat soon ?? Fred.

 

[endecotp]

At some point I'll post a long saga of what & why, but I don't yet know if it should belong in "your projects" or "DIY disasters"...

Yes the RB is to help with soundproofing.

 

[Fred61]

Great. I’ve come across many people in the past doing things cos it seemed like a good idea. Now to answer your question when we fix this stuff we use a 5x50 screw but use a penny washer to increase the effectiveness when double boarding. To help with sound you could also fill the floor void with insulation. Fred

 

[endecotp]

Thanks; yes 5 x 50 seems more sensible than a 3.5mm PB screw.
I'll see if I can find something with a washer/wafer/flat head - whatever that's called - to avoid messing with washers while up a ladder...

 

[endecotp]

Hmmm, but the holes in the bar look very much as if they are intended only for 3.5mm screws.....

 

[Fred61]

We have had issues with small screws pulling through when we have double boarded. Fred.

 

[endecotp]

Was that with joists and bars on approx 450mm centers? I'm probably going to put the bars closer together, which will help a little bit. Time for some experiments.....

 

[Fred61]

That was on 450 spacing on timber.

 

[bobasd]

2400 x 1200 plaster boards fix at 400mm centres.floor joists are setat 400mm centres.
i'd be intrested to see how you geton becos if you use too long screws to fix the board you might end up fixing the board to the joist which defeats the object.
if theres any flex in that floor you risk seam psplits at the board joins skim finish.

my two pee with retro soundproofing is that its a waste of time in a house or flat