fire rating

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BobbyJack

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Anybody know how long gypsum 12.5mm pink fire board is rated to in minutes. Need 60 min fire separation and not sure if single or double birding is required
 
Anybody know how long gypsum 12.5mm pink fire board is rated to in minutes. Need 60 min fire separation and not sure if single or double birding is required

Theres no longer an easy answer to that question BG no longer specify fire rating times for their boards as its more to do with the total system.
 
Always makes me laugh when people want 60 mins protection on bedroom ceilings ...downstairs fair enough . Lets face it your dead well before 60 mins is up but hey as long as the ceilings ok :RpS_thumbup:
 
im sure normal boards are 30 mins and fireline are 60

This is what I was alway led to believe, for single layers.

As with everything specs change. Ask the client to get a spec of BG and price it off that if there that worried.
 
It's for mine mate. Architect not available till Jan and I'm boarding today and tomorrow. Got one layer on ceiling at moment
 
This can be so confusing,building control in different areas want different things on this subject.under and around steels in our area we have to either do one layer of red board or two layers of white,skimmed.tape and joint may be different?
 
ImageUploadedByThe Plasterers Forum1419985771.571051.jpg what's the best way to finish above this stove. Was meshed and skimmed and now cracking.

Fire proof plaster stuff any good
 
so whats the point of fireline if standard plasterboard has 30mins already... if your going to tack a ceiling I rather just do it the once...
if you put up a stud wall with one layer of normal plasterboard either side this gives you 30 minutes,, one layer of fireline on both sides of the stud wall gives you 60 minutes, therefore two layers of fire line on a ceiling gives you 60 minutes, 2 layers of normal on the ceiling gives you 30 minutes
 
if you put up a stud wall with one layer of normal plasterboard either side this gives you 30 minutes,, one layer of fireline on both sides of the stud wall gives you 60 minutes, therefore two layers of fire line on a ceiling gives you 60 minutes, 2 layers of normal on the ceiling gives you 30 minutes

Hmmm never thought about it that way....
 
if you put up a stud wall with one layer of normal plasterboard either side this gives you 30 minutes,, one layer of fireline on both sides of the stud wall gives you 60 minutes, therefore two layers of fire line on a ceiling gives you 60 minutes, 2 layers of normal on the ceiling gives you 30 minutes

Thanks :D
 
The other thing that needs to be considered but is often forgotten is joist size. If it's an existing building and you intend double boarding a first floor ceiling with fire board then 9 times out of 10 the joists aren't up to it.

If you have a bedroom say 4.5 by 5 metres that'd be roughly 16 boards to double skin it. 32kg a board and you have half a tonne of plasterboard hanging off of the joists. Best case, the ceiling will bow. Worst case and henny penny will be proved right.
 
The other thing that needs to be considered but is often forgotten is joist size. If it's an existing building and you intend double boarding a first floor ceiling with fire board then 9 times out of 10 the joists aren't up to it.

If you have a bedroom say 4.5 by 5 metres that'd be roughly 16 boards to double skin it. 32kg a board and you have half a tonne of plasterboard hanging off of the joists. Best case, the ceiling will bow. Worst case and henny penny will be proved right.

Good point that
 
if you put up a stud wall with one layer of normal plasterboard either side this gives you 30 minutes,, one layer of fireline on both sides of the stud wall gives you 60 minutes, therefore two layers of fire line on a ceiling gives you 60 minutes, 2 layers of normal on the ceiling gives you 30 minutes

That only gives 15 minutes then..... Because if it gets past one board its at the timber which is what the fire protection is trying to stop otherwise the wall isnt a wall ...... The fire would normally be on just one side of the wall ..... And the aim to stop the fire penitrating through to the structure ...... Well thats the way i would think .....
 
It use to be 45 minutes for normal boards, hour and half double boarded but crossed, back in the day of clout nails every 6 inch, either way its screws/nails melting that spread the fire, fibre in fire board hold it longer to the screws/nails , Every architect will have various ways to combat this and various times, schedules and needs. its been a long time since I have read white book and just do what's specified via architect/ manager ,some go with belt and braces attitude and that's fine as long as it saves life's , long winded I know .... Happy new year to one and all!
 
Wow its getting complicated now... lol @RobJack :-/
you could ask a hundred people this question and get a hundred different answers ,, only about 6 weeks ago i was in a office with about six different people, all had different views and all spent ages surfing the net for answers,, agreed in the end that ceilings would need 2 layers of pink to get one hour, hopefully its something none of us get to put to the test,
 
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