Protecting Garage Door Insulation

[thrytis]

Continuing this thread on insulating garage doors, i painted my foam board insulation with a mix containing Flame Stop III in order to protect the insulation from fire, as required by the local building code. As an after thought i also put some on a scrap of insulation so i could test out.

I got around to testing my scrap piece the other day. I held the board vertically and held a butane lighter against it for ten seconds, then removed it. The uncoated insulation melted, caught on fire, but went out almost immediately after removing the flame. The Flame Stop III coated insulation melted, caught fire, and continued burning and expanding when the flame was removed! It burned less than the insulation coated with untreated paint, but it was still noticably more than the uncoated insulation. I contacted Flame Stop about this, and was told that Flame Stop III is not intended for insulation applications.


Flame Stop suggested Flame Stop I-DS (applied at 100 sq ft/gallon, about twice the normal application) for this purpose. They're sending me a sample to try. I'm getting tired of taping and painting the door, so i'm looking for other suggestions to protect the insulation on the door besides another paint on coating or tearing out the insulation and replacing it with something like Thermax. One thought i had was using a radiant barrier such as this, but i've never held the stuff so i don't know if it would melt and expose the insulation. It is class A/class 1 fire rated so it won't burn itself, but is that enough to protect what is behind it? The other idea was some thin metal or other fire proof sheets, but i don't know what could be used. Whatever the cover, it would need to be fairly light weight and not be too expensive (starting from scratch with Thermax i think would only be a little over $100).

Does anyone have any suggestions?

Thanks!

[Gotcha6]

If your door springs will stand the extra weight I'd try a product called Glasboard. It's a fiberglass resin board about 1/16" thick & textured. Available in 4' x 9' sheets if you need it - and colors too. You may have seen it on restroom walls or kitchens. It does have a fire resistance rating and cna be glued to the insulation or pop riveted to the door panel frame. Just be sure to have your mask and safety glasses on when you cut it with carbide tipped blades or a jigsaw. It's itchy stuff.

[mkepke]

Eric - I never did get around to using the FSIII myself. It's still sitting in a pint container on my desk

Your results are very surprising - but thanks for testing and reporting.

It looks like I'm also in the hunt for a new fire retarding solution.

I wonder how foil-faced board performs ? My other thought is maybe the foamboard could be covered in a cheap fabric like muslin or burlap and then paint *that* with the retardent.

Or maybe I just turn up the AC.

-Mark

[thrytis]

Dennis, do you know where you can get the glasbord? Do they carry it at big box stores? The only place the manufacturer lists in NC is Atlantech, but dealer locator lists aren't always comprehensive. It sounds like the type of stuff i'm looking for, though it may be a bit heavy for the door. It looks like it probably would be about 75 lbs for the door.

Mark, i'm supposed to have the sample of FS I-DS by tomorrow, and plan to test it out even if i find another solution. I'll let you know how that works.

[John Reeves]

I put "duct wrap" on top of the foam insulation. The duct wrap is foil backed and uses the pink fiberglass for insulation. I do not remember anything about fire retardation regarding the duct wrap though.

It does stop the drafts coming from between the hinged doors of the roll up garage doors. I stapled it on through cloth duct tape.

[jmauldin]

On my doors I used 1/2" blueboard attached with calk adhesive and then covered the inside with the foil tape used for heating and air conditioning. I have no idea how fire retardant that is, but I figured the aluminum foil tape should withstand the heat and certainly wouldn't catch on fire. Besides, it didn't take that many rolls. I don't know if that is code or not, didn't ask, and don't care. It certainly made a difference in my heating and cooling.
Jim in Mayberry

[junquecol]

[quote=thrytis;93709]Continuing this thread on insulating garage doors, i painted my foam board insulation with a mix containing Flame Stop III in order to protect the insulation from fire, as required by the local building code. Is the purpose of this coating to satisfy the local building inspector? If they approve it, don't sweat it. In a fire, I can tell you that you will be a lot more worried about your tools, than the garage doors.

[thrytis]

Originally Posted by junquecol

Is the purpose of this coating to satisfy the local building inspector? If they approve it, don't sweat it. In a fire, I can tell you that you will be a lot more worried about your tools, than the garage doors.

I don't have plans to have anything inspected. The main motivation for the covering is just to "do it right". I would rather deal with it now rather than, for example, have to mess with it when selling the house 10 years from now. Honestly i'm not too concerned about the safety issue because insulation on a steel door is likely to be less of a problem then stacks of lumber, piles of newspaper, and cardboard boxes also in the same space.


Jim, John, thanks for the suggestions. I imagine both the duct wrap and the foil tape would make a pretty good fire barrier and be pretty light weight.

[thrytis]

I'm still waiting on the Flame Stop I-DS, but i did receive a sample of radiant barriers from Radiant Guard. Unfortunately the faces are too thin to protect the core, which causes it to crumple and ignite when exposed to a flame. Possibly a large sheet secured by foil tape might be okay (definitely better than exposed insulation), but overall it seems kind of iffy to me. I'm kind of disappointed because i was hoping to use the extra in the attic to see if a radiant barrier would make a difference on heating and cooling costs.

[thrytis]

I finally received my sample of Flame Stop I-DS and i'm in the process of applying it to a test sample. It doesn't look very promising. The stuff beads up on almost every surface i'm trying it on, and on bare blue foam applying the second coat with a spray bottle was enough to wash off what little stuck from the previous coat! I should have test results in a couple of days.

[Gotcha6]

Atlantech Distribution is a company located in Arrowood Industrial Park off Westinghouse Boulevard(just north of Carowinds). They may sell to individuals or be able to give you a retail outlet source. You've probably seen this stuff before and didn't know what it was. It's used extensively as a cheap washable surface in meat cutting rooms, restrooms, etc. in lieu of ceramic tile. You could wash it with a pressure washer if you wanted. The surface is embossed.

[Alan in Little Washington]

I would just use fiberglass insulation. My metal doors are just backed with vinyl covered fiberglass insulation. While the vinyl will burn, the glass will not. Any kind of foam insulation will likely burn more and may produce toxic gas as it burns.

If you want insulation and a certain amount of fire proofing, use some type of insulation covered with Fiberfrax woven ceramic cloth, a product used in the aerospace industry. Some commercial and homebuilt aircraft builders use it to cover aircraft firewalls.

Aircraft Spruce and Specialty sells it retail, but it is pretty expensive.

[thrytis]

Originally Posted by Alan in Little Washington

I would just use fiberglass insulation. My metal doors are just backed with vinyl covered fiberglass insulation. While the vinyl will burn, the glass will not. Any kind of foam insulation will likely burn more and may produce toxic gas as it burns.

Fiberglass insulation? Like the pink stuff that comes in rolls? I wouldn't think an inch and a half of that would provide much insulation.

I've seen the vinyl backing on the garage doors and wondered what was under them.

[Gotcha6]

I just picked up an HD flyer this week that showed FRP panels being offered in the Charlotte stores. You might want to check it out. Be sure they show you the accessories & mouldings for this system if you ask. There is a full compliment of i/s & o/s corner, 'J', & 'h' mouldings available as well as drive anchors for attachment.

[Bernhard]

What about using galvanized 24ga steel? Any HVAC shop has plenty of it and will cut the pieces to fit. Place the insulation in the doors and cover it with thin steel. No fire hazard and protects the fiberglass. Then just use some self tapping screws to and you are done.

Bernhard