Fire protection - Ceiling in garage

[frediaz]

I am confused: for a dwelling where the construction started in 2006, the ceiling on a garage, with a bedroom above (joists floor) does it need 30 min or 60 min fire protection according to the regs. There is mineral wool between joists.

Another thing, why use the expensive Fermacell, when it would need two layers of 15mm board if it is 60 mins? Is it not better just to use the cheaper Fireline?

 

[opcom]

2 layers of british gypsum 12.5 boards will give you 60 mins, but you must make sure that the boards are staggered and fire tape (jointed) does not need to be to a good finish but must be taped and also some form of fire sealant to the edge of boards where they meet the external walls.

HTH

 

[opcom]

A quick message to a moderator - my username seems to have changed, and I can't find a section on who are the mods.

Can you advise why the name change.

Many Thanks

 

[roughcaster]

Probably because you are/were, using a "web address" as you're username,, tut tut,,,, not allowed. Opcom sounds much better anyway.

Roughcaster.

 

[opcom]

And I bet you don't do roughcast plastering

Ok not to worry - the advice is still the same on the ceiling though

 

[frediaz]

Just one thing, has the regulation changed? because I started the construction in 2006 and have part B from that date, which says 30 minutes between garage and house, hence my confusion.

If I use 2 layers of plasterboard, do I need to skim it? I am not too worried about the finish in the garage

 

[opcom]

A google search seems to suggest 30 mins is ok , however a quick call to the local council building regs guy will put your mind at rest.

That said for an extra layer of plasterboard should not cost you that much and you get and extra 30 mins and if there was a problem may be the best money you ever spent!

You will need to tape the joints one way or another, if your doing it yourself and bag of easifil from local builders merchants should do the job just fine.

HTH

 

[trowelmonkey1]

regs changed in 2007 so if the regs before that say 30 mins then you're good to go but like opcom says, a bit of extra board and elbow grease might be worth considering.

not sure if there is any special type of filler for fireboarding though, don't need to skim it if you don't want to, the board is doing the protection.

 

[trowelmonkey1]

never used fermacell, why were you considering it? what properties does it have that gyproc fireline boards don't?

 

[frediaz]

never used fermacell, why were you considering it? what properties does it have that gyproc fireline boards don't?

because someone told me that it does not require skimming and it does not need fire joints, just the glue on the edges

 

[frediaz]

So my understanding is that if I put 2 layers of 12.5mm plasterboard, it does not need to be fireline, just ordinary plasterboard, but I need to cover a steel beam, so will 2 layers of ordinary plasterboard do for it?

I guess the skimming would have been necessary to complete the fire protection, but with 2 layers of plasterboard, it's not needed

 

[opcom]

frediaz

This pdf might be of some help to you - it's from the british gyspum website http://www.british-gypsum.com/literature/white_book/floor,_ceiling_and_soffit/timber_joist.aspx

 

[frediaz]

Thanks for the feed-back. By the way, for the benefit of others, I spoke to Lafarge technical support and they told me that skimming the plasterboard makes no difference to the fire barrier properties. It is the plasterboard that does that.