2 Hour Fire Separation

parko202

I am working on a project in Canada and am having difficulties achieving a 2 hour fire rating for the floor system (refurb). I know the NBC will be different here but has anyone used any techniques which do not require gyproc'ing the ceiling (floor joists are not level so a great deal of work with shimming etc.) or a sprinkler system (space is an issue and it needs to be kept inside in winter due to freezing).

At the moment, the timber flooring for the upstairs rests on the ceiling joists for the downstairs. Not ideal however the ceiling height is reasonably low anyway without closing in the space with gyproc. Fire marshall will not accept an intumescant paint until there is stated evidence it could give a 2 hour rating.

Any help or suggestions would really be great.

Poor Uncle Tom

The trouble is that the fireproofing has to be on the room side of the structural element, in this case the joists. Would taking 30mm off the overall height be so detramental?

parko202

Well the problem is that it is an old cow barn so there is not a huge amount of light getting in anyway, close up the ceiling joists and this is going to further increase the "heaviness" of the room. The building has been converted to rental accommodation aswell so it would be detrimental to the rustic aesthetic.

Poor Uncle Tom

So could you not follow the rafter line around and expose the joists like collars.

sydthebeat

what about foamed vermiculite between joists???

it may not give you 2 hr on its own but, in conjunction with maybe impregnating fire treatment to the floor boards of upstairs you could achieve 2 hr..?

parko202

Poor Uncle Tom wrote: »

So could you not follow the rafter line around and expose the joists like collars.

Not really sure what you mean on that (very little construction experience). Would that be go between the joists and just have their ends exposed?

The vermiculite could work, am trying to find someone who does it at the moment. There is very little knowledge of building code here as it does not apply outside of the main town. The only reason we have to comply is that it is going to be used by the public.

sinnerboy

I would start making calls to those on this list

parko202

Actually, I had called a number on that list and each time it was met with:

"Prince Edward Island, don't know a thing about how you do things there!"

There is one person who is looking at it in terms of a sprinkler system design but I reckon that will be quite costly and would like to have a number of options for my boss when it comes down to it.

dan_d

OP I've just come from a job where we had that problem in a number of places. Head height wasn't an issue, but achieving a 2 hour rating on a floor, or structural beams was.

To be honest, the only solution we could come up with was to wrap the beams (which were intumescentally painted) with gyproc. We did investigate other methods...the only one we could find was a paint that could be used, however it was extremely expensive vs what we had to move to wrap the beams in boards, so we just went with the second option.As far as I can remember, the paint wasn't guaranteed to give us the 2 hr rating either.

Sorry I can't be more help...do you have a fire consultant, and could you talk to them about any products they might be aware of? I don't know how it works in Canada, but certainly here, the fire consultant and the fire marshall were 2 seperate entities, so you could ask one a question to get around the other, if you get my meaning.