Plasterboard around universal beam?

[pharmaboy2]

Problem - how to provide timber connection points to allow the attachment of plasterboard to cover universal beam.

I am intending on running ceiling joists housed out to be either flush with the bottom of the steel beam, which would allow the plasterboard to be nailed to the ceiling joist and then glued to the base of the universal beam on the horizontal, then for the vertical a plate on both the top of the beam and the top of the flange to attach plasterboard to.

OR

housing out ceiling joists 35 mm with the botttom of the ceiling joist continuing past the bottom of the steel beam, meaning the ceiling plasterboard only attaches to timber and doesnt need to be glued to the steel. (the very dodgy drawing attched might help with this)

So the question is whether glueing to the steel while nailing to the timber is poor method for attaching plasterboard, or whether its totally acceptable - given that option 1 above is by far the easiest to achieve.

plasterers help greatly appreciated, so i dont set up, and the plasterer, says "mate I'll have to redo all that with rondo etc etc"

[Barry_White]

Pharmaboy

Just to clarify does the joist continue on the other side of the universal beam. If it does there would be no need to glue the plaster board to the beam and just let it span under the beam and attach it to the joist on both sides.

[silentC]

Use battens.

[silentC]

Had a look at your picture (should've done that first).

So you want to box it in? What's above the beam on the right hand side of your pic?

[pharmaboy2]

yep box it in (well half boxed, the other side finishes hidden by the bulkhead), so no continuation. On the RHS of the pic is the existing ceiling attached to the underside of floor joists to the upper story. So i suppose you could best describe the finished product as a bulkhead that hides the universal beam - in this case a ceiling drop of about 400mm to the underside of the steel, and then horizontal to the outer wall.

pickies of the current situation (ie rafters but no ceiling joists)

[silentC]

OK so you want to bring the new ceiling in at the bottom of the beam and have it wrap around to meet the existing plaster at 90 degrees.

What I would do is set the ceiling joists into the beam. They don't need to be checked in, they can just sit on the flange anchored appropriately. Then I would run battens on the bottom of the joists with the last one abutting the edge of the beam. The batten height will take care of the difference in height between the bottom of the joists and the bottom of the beam.

For the vertical side, I would make up a frame from 2"x3" and suspend it from the existing joists and anchor it to the beam at the bottom. Then battens on that too. The bottom of this frame finishes at the same height as the bottom of the new joists so that you put a batten on the bottom plate of the frame and everything is in plane.

Does that make sense?

[silentC]

Actually, the couple of times I've done that in the past, I've just had the chippy box the beam in and have both sides of the ceiling at the same height, so it's treated more like a doorway if you get my drift. Maybe you've got a reason you don't want to to that?

[pharmaboy2]

yep, makes sense silent. If i'm battening, I'll probably space joists out at 900 centres (was doing 450's to attach to sides of studs), which should leave enough timber over to nearly batten it all before tripping off to timber yard.

[silentC]

Alternatively, you could run your joists parallel to the beam (use a hanging beam if the span is too wide) and then run your battens right through past the beam and onto the bulkhead frame. That way nothing is anchored to the beam and the battens would tie the whole thing together if you're concerned about movement.

[pharmaboy2]

Actually, the couple of times I've done that in the past, I've just had the chippy box the beam in and have both sides of the ceiling at the same height, so it's treated more like a doorway if you get my drift. Maybe you've got a reason you don't want to to that?

purely a question of style and design. Boxed in looks like hell, there's obviously a beam inside there, whereas bulkhead, says "look, this defines theentertainment area with different paint and different lighting blah blah blah...." Same dropped ceiling height (still a 2800 ceiling in the dropped section) goes outside too.

[silentC]

Yep fair enough, although I've seen the dropped ceiling look pretty ordinary too. It says "this is an extension"

But it can look good if you do it right and think about it, which you obviously have done.

[rod@plasterbrok]

Simple method is to check the joists flush with the bottom of the beam.

The plasterboard will carry the width of the beam. Put glue direct onto the beam.

A clever plasterer would then cut and fold the sheet for the side of the beam and just attach to the plate at the top of the beam. With an external angle on it it will never move.

If your plasterer is not so clever you could simply liquid nails a batten on the inside of the beam to fix the bottom of the face sheet to.

No need to batten out.

Cheers.

Rod

[silentC]

Well there you go, from the horse's mouth. Intuitively I wouldn't feel right about gluing it to the beam but if Rod says it's OK go for it. I also use battens as a matter of course but then I've only really worked with trusses and you can never rely on them to be straight.

[pawnhead]

Simple method is to check the joists flush with the bottom of the beam.

The plasterboard will carry the width of the beam. Put glue direct onto the beam.

A clever plasterer would then cut and fold the sheet for the side of the beam and just attach to the plate at the top of the beam. With an external angle on it it will never move.

If your plasterer is not so clever you could simply liquid nails a batten on the inside of the beam to fix the bottom of the face sheet to.

No need to batten out.

Cheers.

Rod

Or you could preform the bulkhead with a V groove router as we just discussed in the other thread. No need for an ex angle then. A bit tricky to do though.