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Charles Bickford mentions fireproof caulk for sealing wire and pipe framing penetrations in his article “Preventing House Fires”, June/July 1999 FHB, No. 124, page 68. People at Home Depot and several local home supply companies have ever heard of it. The local fire chief knows it exists, but has never seen it used and doesn’t know who makes it.
Does anyone know where to get fireproof caulk?
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Replies
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Lowe's had it here for about $6 a tube. Or try an electrical or plumbing supply house. Both our electricians and plumbers used it around their openings, and I assume they got it at their normal supply house. It's code here in NC. An alternative is rockwool. The inspector suggested I use that for some spaces not conducive to caulk. I got that at a drywall supply house.
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While trying to find acceptable ways to fix one of two 'broken' woodstoves, I learned from two different woodstove shops that plain old pure-silicone caulk is acceptable to seal the fireboxes on these things. Nearly indestructable in flames/heat.
They also sell a woodstove and fireplace 'mastic' in a caulk gun tube.
*Greg,What you're looking for is probably elastomeric firestop sealant or intumescent firestop sealant. Go to http://www.sweets.com and search Division 7, 07270 - Firestopping for product data. Call the manufacturer of your choice and enquire about local vendors.Luka,Silicone sealant for fireboxes, huh? I guess that explains a lot. Burn hot and breathe deep my friend. As for me, I get a headache just breathin' the stuff raw, let alone cooked! It's obvious you've reached a "higher" plane than I! (LOL)
*hahaha Didn't say I'd done it. Just said that's what was told me at two different woodstove shops.I bought the mastic sealant instead. And now, thanks to your post, I'll take it easy when I use even that. I'll seal the firebox with the mastic and then burn it hot for a couple days outdoors to see what happens before I bring the puppy inside.Thanks. : )
*Home Depot has it. It is in their water heater section next to the ductwork, flanges, and doublewall vents. The stuff is great, but dries rock hard, and dries very, very quickly. I mean in about 1-3 minutes, so work fast.
*Eric,Thanks for the info. Perhaps to expand on your post:It is my understanding that there are different "fireproof caulks". The intumescent you refer to actually expands with extreme heat, blocking hot gasses and flames. Other high temperature mastics will not do so, and are not acceptable for caulking penetrations through firewalls (at least where I am). I'm not sure what you'll find at HD, Lowes, etc.An important distinction, I thought.Adam
*Better check with your building department before you buy any. We are just finishing a remodel in a city we've never worked in before. When it came time to draftstop, we bought the firestop caulk at the local yard (14.00/tube) and the only reason it passed was because the real inspector was on vacation and a substitute signed off on it. When the regular guy came back for insulation inspection, and saw that stuff he was none too pleased. Took an empty tube back to his office and came back and field tested the expandability of the stuff. Said that he really shouldn't pass it, but since it had been signed off he let it go. Pretty crazy, huh?There are certain ASTM standards that these products must pass - be carefull not to simply accept the advertising on the package.
*Fire proof caulk is good to about 4000 degrees I'm told by one inspector. Unlike some of his fellow inspectors, he feels it is unnecessary. I tend to agree. In single family residential const. what purpose does it serve, if the whole building burns up, but the caulk is still there? Many building officials seem confused about the difference between a draft stop and a fire stop. Firecaulk is appropriate in fire walls, but not in most residential applications, something less expensive and more available is a better choice, except of course inside your wood stove.
*Whatever its merits, the fact remains that some city/county inspectors expect to see the penetrations sealed with fire caulking.Although Lowes has taken some knocks in this forum, I happened to be in our local code compliance office when someone from our new lowes store called to check on what sort of fire caulking they should carry to meet local codes. I thought it was good of them to check. They've got it now, as do the electrical and plumbing supply houses.Good luck, Steve
*Whatever material you use to seal framing penetrations make sure it complies with ASTM E-136. That should please the most finicky inspector.
*Hilt makes a product called FS-ONE. It is called a high performance intumescent fire stop sealant. We have been required to use at the bottom of the ridge on devising walls. (wood frame town houses) It costs $ 16.00 per tube. I felt the inspector was way off base on this. Because the wall did not penetrate the roof to create a parapet, the decking would burn across to the next unit rendering the caulk useless. But ours is to do and not question or get a boat load of red tags.
*I believe th idea with the intumescent (swelling) stuff is to use it around things that will disintegrate in the heat, such as wires, pvc pipe, etc.? And the fireproof stuff (once asbestos-laden I bet) is for sealing around stovepipes and the like? Any cut-and-dried distinction?The intumescent is very expensive... $14 a tube?
*My inspector in CT insisted on ASTM E-136 caulk. Apparantly, that's all that's acceptable under CABO. I have to question that spec, however. The E-136 caulk dries hard and inflexible. If there is a fire within a framing cavity, I imagine the plastic pipe or wire insulation melting quickly and a perfect ring of E-136 caulk falling downward whilst the flames shoot upward. Although intumescent caulk emits some smoke when heated (the reason, according to my local inspector, that it doesn't meet the E-136 standard), that seems to be of minimal concern when balanced against the fact that intumescent caulk might expand enough to fill the hole and buy a few more minutes before the flames spread to the next cavity. I used E-136 caulk, but retrospectively, I wish that I'd used E-136 on top of the plates and intumescent below them.Andy
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Charles Bickford mentions fireproof caulk for sealing wire and pipe framing penetrations in his article "Preventing House Fires", June/July 1999 FHB, No. 124, page 68. People at Home Depot and several local home supply companies have ever heard of it. The local fire chief knows it exists, but has never seen it used and doesn't know who makes it.
Does anyone know where to get fireproof caulk?