Pasterboarding an RSJ

[stephenstern]

I have some half (plasterboard wall between) RSJs to cover before they can be plastered.

Looking online, there are a few methods.
Noggins larger than rsj, screw PB to the side and underneath - as the noggin comes out further. However that makes a larger "box".

Noggins which line up to outer edge of RSJ. PB side with screws and gripfill\pinkgrip PB underneath.

Same as above but one PB sheet which is folded over side, screwed and glued underneath.

I'm feeling the last option as its a small beam.. like a meter or so.

Opinions?

Pinkgrip or gripfill, normal or solvent free?

Cheers guys

 

[kazuya]

I knock noggins in the sides then I try to cover the beam in one piece of board by just scoring one side of the board then folding it over to the shape of the beam then slotting it up and over then screw the sides.
it is a two man job but works well

 

[stephenstern]

Yea does sound like the better option. Do you glue underside?
Do you have the cut on the outside or inside. inside would make more sense, leaving a paper outside but means more trimming to get the 45' cut to fold

 

[kazuya]

you can use dot n dab or something on underside if you like but once its got the beading on and is skimmed it will be solid enough anyway.

you can only cut the outside or it wont fold the right way
try it on a small piece, cut one side then just snap the board the opposite way, you'll see what I mean

 

[stephenstern]

See below. best paint drawing

Untitled

• stephenstern
• 18 Mar 2015
• 1

 

[kazuya]

yea I wouldn't bother doing all that, that may look feasible in a drawing but in practice that would be a nightmare to do without ripping the paper off lol
just cut the outside, if you want to make the corner stronger fill the beading with dot n dab then stick it on.
when its skimmed it'll be rock solid

 

[noseall]

The simplest (correct) way is to have holes drilled in the web. You can then insert a suitably sized piece of timber in each web recess and bolt or coach screw the sandwich together.

You then need to double board the beam with fire-line plasterboard.

Noggings can become loose as the beam warms in a fire.

We always take into consideration the thickness of the finished beam plastering relevant to the adjacent walls etc, and try to marry everything in. You don't want to see lots of dog legs or short quick recesses, just nice straight lines.

 

[stephenstern]

There is not much point in screws, its literally 5 or 6inc by 3inc.

What adhisive should i use?

pinkgrip or gripfill?
normal or solvent free?

Make any difference?

 

[noseall]

What adhisive should i use?

Board adhesive i.e. Knauf bonding compound etc.

 

[stephenstern]

It doesnt say thats any good to metal? Also bit large and messy for my needs, just for a 6cm x 60cm bit of board.

 

[kazuya]

I don't think itll make much difference what you use, its only a small piece

 

[stephenstern]

yeah, more of solvent or solvent free..
i bought the solvent version anywho.

 

[noseall]

Yeah you two guys have it cracked. Just do it how you want and stuff any fire safety regs.

 

[kazuya]

Yeah you two guys have it cracked. Just do it how you want and stuff any fire safety regs.

how do you know he's not going to double board it?
he only asked how to attach the boards to an rsj

 

[noseall]

how do you know he's not going to double board it?
he only asked how to attach the boards to an rsj

Why would the amount of layers of plasterboard matter when the lot falls off when the beam warms up a bit.