Fireblocking Help Needed
#1
01-19-13, 08:41 AM
Join Date: Jan 2001
Location: USA
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Fireblocking Help Needed
I am in the first stages of finishing my basement. I have put 1" XPS on the walls and in the rimjoist area. My question is about fireblocking. I have not submitted my plan yet but spoke with the inspector regarding fireblock and he said I could use 1/2" sheetrock butted up to sill plate and the top plate attached to joist through the sheetrock. I have attached pictures of what I think this means. Correct?
What do I do with the rim joist area? Can I stuff with rock wool?
Also I am going to put in a surface mount ceiling system.
How do I properly fireblock with a suspended ceiling?
Help would be appreciated. I have a software program for the design that will produce the plan that I need I just wanted finish the foamboard insulation first.
What do I do with the rim joist area? Can I stuff with rock wool?
Also I am going to put in a surface mount ceiling system.
How do I properly fireblock with a suspended ceiling?
Help would be appreciated. I have a software program for the design that will produce the plan that I need I just wanted finish the foamboard insulation first.
#2
01-19-13, 08:59 AM
Group Moderator
Yes, I think that's what he was suggesting.
As for the foam that is exposed along your rim joist, since the product you used is not a foil faced product like Thermax (in the US, foil faced foam boards are usually fire rated, but in Canada no foam products may be left exposed), the foam between joists must be covered with a 15 minute fire barrier such as 1/2" drywall. You will probably want to trim off all the excess spray foam (multi-tool like the Fein Multimaster works great for this) so that your drywall will fit nice and snug. If your inspector is nice he won't make you fire caulk the edges of the drywall, provided your drywall fits nicely. (use a drywall rasp on all 4 edges)
Rockwool may work as the 15 minute barrier, but it wouldn't hurt to clear it with your inspector, since he may have a problem if it is simply stuffed in. (if it falls out or blows out- as it might with a backdraft in case of fire)
In commercial construction, ceilings are drywalled and fire taped, then drop ceilings are hung. I don't think anyone requires that in residential, unless the building is rated as a class 1A occupancy structure or similar. (such as multi-unit housing, etc)
As for the foam that is exposed along your rim joist, since the product you used is not a foil faced product like Thermax (in the US, foil faced foam boards are usually fire rated, but in Canada no foam products may be left exposed), the foam between joists must be covered with a 15 minute fire barrier such as 1/2" drywall. You will probably want to trim off all the excess spray foam (multi-tool like the Fein Multimaster works great for this) so that your drywall will fit nice and snug. If your inspector is nice he won't make you fire caulk the edges of the drywall, provided your drywall fits nicely. (use a drywall rasp on all 4 edges)
Rockwool may work as the 15 minute barrier, but it wouldn't hurt to clear it with your inspector, since he may have a problem if it is simply stuffed in. (if it falls out or blows out- as it might with a backdraft in case of fire)
In commercial construction, ceilings are drywalled and fire taped, then drop ceilings are hung. I don't think anyone requires that in residential, unless the building is rated as a class 1A occupancy structure or similar. (such as multi-unit housing, etc)
#3
01-19-13, 11:02 AM
Join Date: Jan 2001
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In my attached crude drawing. The blue line is foamboard on top of the wall between sheetrock and top of wall. The brown rectangel is a top plate against the sheetrock. Is this acceptable?
Where the arrow is pointing- I can clean this up and then stuff rock wool in there most likely?
Surface mount suspended ceiling-It attached to the floor joist. I want to put insulation in between the joist then the ceiling. What type of fireblock do I need?
Where the arrow is pointing- I can clean this up and then stuff rock wool in there most likely?
Surface mount suspended ceiling-It attached to the floor joist. I want to put insulation in between the joist then the ceiling. What type of fireblock do I need?
