Plasterboard ceilings and lining bathrooms

[Renovating fool]

1. Ceilings fixed to furring channel - what gauge to use

I am trying to decide whether to use 10mm or 13mm plasterboard on ceilings. I understand that if you use 13mm you can increase span between channels to 600mm from 450mm.

Just wondering if anyone has done the numbers and can tell me which is more cost effective, or if one option gives a better result?

2. Furring channel resilient mounts.

These are referred to in gyprock brochure - can't really understand why you would use them. Is it to reduce noise or deal better with house movement. We are on reactive clay soils in a house that was built in 1830, so I am expecting some movement.

3. Using gyprock ceilings for bathrooms.

I am using villaboard or equivalent on bathroom walls, however wondered if I could do gyprock ceiling instead of finishing through with vb.

Brochure I have on plasterboard ceilings is silent on use in bathrooms. Anyone able to confirm if this is OK? The ceilings are 2.8m high and exhaust fan will be installed to take away steam etc.

4. Moving cornice

I have installed a bearer & joist floor inside double brick walls. Due to reactivity of soil these will move independently. I therefore intend sealing wall sheets to furring channel (allowing sheets to move up and down on walls) and also sealing wall sheets to floor as part of waterproofing.

This will see the whole bathroom "move" up and down inside the skin of the bricks (which will avoid tile cracking and so on). Only issue here is therefore that the cornice need to be able to move up and down the wall as the bathroom rises and falls on its independent floor.

Material I have read mainly sees cornice joined to both wall and ceiling. Anyone know where to get info on how to do it the way I want to?

Thanks

Matt the renovating fool

[sol381]

As for statment 1. dont bother about 13mm board. Stick to 10mm much lighter and it can easily span 600mm . Celing board is different than wall board as it it is fibre glass reinforced.

2. resiliant mounts do reduce the amount of noise but im not sure just how much. Theres not much more work installing them but cant be sure its worth it. Better to ask your supplier.

3. Its ok to use plasterboard on the ceilings. Just be sure you have an exhaust fan or the paint paper will peel away.

4. NOt sure how much movemenmt your plan to get but i doubt whether you will get the cornice to move. It is glued to wall and ceiling and sticks like biuggery. If your worried abotu tiles cracking use a flexible tile adhesive.
stef

[ausdesign]

Stef - are those ceiling sheets a qld. thing ?

Standard gypsum plasterboard spans 450 for 10mm & 600 for 13mm.
10mm 'ceiling' sheets are available from several manuf. to span 600 but they need to be ordered as such and to my knowledge they're not glass reinforced but i stand to be corrected.

[BrisBen]

Ausdesign - they are national and we use them commercially all the time (not sure if the cottage boys use them - they often have timber framed joists that are at 450 centres)

I have never needed to make special orders for any of the below, as for the reinforcing I am not sure what it is but you can often see small fibres in the gypsum when you cut the board - who knows; could just be lesser refined gypsum (I'll check the MSDS). I do know that Australian Plasterboard uses a heavier weight paper (230 gsm as apposed to 180 gsm) on their board and it is smoother

Gyprock brand is known as Supaceil and is readily available from Gyprock Trade centres and the 10mm sheet designed to bridge 600mm spans

http://www.gyprock.com.au/common/category.asp?catalog%5Fname=Gyprock&category%5Fname=Plasterboards

Australian Plasterboard Company's product is simply called 10mm Ceiling board and again can bridge a 600mm span

http://www.austplaster.com.au/products.php

Lafarge call theirs span 600 and is similar to the others

http://www.lafargeplasterboard.com.au/PlasterBoard_Display.asp?ProductID=9

Renovating fool - you didn't say what you were fixing the furring channel clips to on the ceiling - roofing joists?

[Pulse]

1. Ceilings fixed to furring channel - what gauge to use

The ceiling boards (Lafarge-Span600, Boral- Unispan, CSR - supaceil) is reinforced, just break it and see. They are all 10mm products that span 600mm.

2. Furring channel resilient mounts.

I've used these in the ground floor ceiling after removing carpet upstairs, they lessen impact sounds like foot steps. They are expensive at about $4 each. I've been pretty impressed.

4. Moving cornice

Just use the cornice like normal. If you have used furring channels for the ceiling it will already have some ability to move. If you are really worried use shadowline or similar products by Rondo to replace the conventional cornice.

Cheers
Pulse

[sol381]

I`ve just starting using a new supplier called bgc plasterboard. They are a perth based company and the australian plasterboard company distribute their product. They use a very fine layer of fibreglass in their ceiling sheets for added strength. As for the wall boards they are a bit heavier and stronger than other brands because, i was told, they dont blow air bubbbles into the plaster to make it lighter. They gave me extremely good prices off the bat and after 1 use i`m sure to use them again.
Pulse is right, most are called supaceil or similar name. Dont use wall board on the ceiling because there is a chance of it bowing under the weight. Ceiling board is readily available and only about 5-10% more expensive than wallboard.
stef

[Renovating fool]

Thanks Stef & Pulse, good info. Re ceiling fixing, yes will be fixing ceiling to furring channel as ceiling joists are all over the place.

Currently in the process of fixing furring channel to walls, ceilings will be the next job.

The fool