RMax rigid foam insulation board

[greenleafpharm]

Hey guys, just wanted to know what everyone thinks of the
"Rmax Thermasheath-3 2 in. x 4 ft. x 8 ft. R-13.1 Polyisocyanurate Rigid Foam Insulation Board" Thermasheath Rmax Thermasheath-3 2 in. x 4 ft. x 8 ft. R-13.1 Polyisocyanurate Rigid Foam Insulation Board-613010 - The Home Depot
Included the link to it^^
I've heard some good things about them but I'm concerned about the reflectivity of them and I also heard/read online that they are not too safe in grow rooms. Please let me know, thanks guys!

 

[TorturedSoul]

At a glance, it looks like the kind of product I'd consider if I lived somewhere in the Arctic where, for the majority of the year, my main concern was that my plants might get too cold.

I do have concerns that my plants will get too cold - in Winter. But my location also experiences Summer and, however hot it gets here (we occasionally see 100°F here, but generally our highs are "only" in the mid- to upper-90s), the warmest part of my house is going to be in the grow space. Even in Spring in Autumn when it's at least theoretically possible for entities other than escaped denizens of Hell to get comfortable, I still have to remove heat from the grow space. Therefore, for about ten months out of twelve, a product with such a high insulating value would be a handicap for me.

In addition to that, I'm not comfortable with the idea of priming and painting foil-faced insulation, lol. That means, if I was constructing a new grow space and wanted to utilize this product, I would still end up having to drywall, prep, prime, and paint. Which would be a good thing, since this product is not approved as the "top layer" in construction; by that, I mean it is meant to be installed within walls, not used as the wall surface, itself. In the event of a fire, it's going to release a great deal of toxic fumes. Inside a wall, that's a concern of course, but by the time it ignites your home will likely already be fully engulfed. If, on the other hand, it's the layer you see when you look at your wall, it could conceivably ignite - and begin killing you - at a time when you might otherwise still be able to escape.

Again, if you live in a place where the climate is more or less the opposite of mine - where you have to fight low temperatures for nine or ten months per year instead of high temperatures - then I can see how this could be a useful product. But sheathe it within your walls; do not use it as your walls.

If you run a fully sealed grow room, air conditioned and with CO₂ supplementation, it could also be useful (with the same caveats). You'd already be dealing with the heat your grow space produces, and might wish to create a barrier between that space and the rest of your home.

 

[YzMedic]

It says it is fire resistant. Looks like good stuff.

 

[TorturedSoul]

Most man made building materials are fire resistant these days. I wouldn't break a chunk off and throw it into a campfire though, because about 100% of it would catch fire. That's why they don't print fireproof on it.

I wouldn't misuse it by placing it on the outside of an interior wall. You can, of course, do what you want - and it's pretty clear that you intend to. My warning is intended more for the other people who might read this thread in the future.

 

[Greenleef]

I thought about using that as well . Then in the same isle i seen the reflectix , so i went with that . Although the boards are cheap , 8 bucks each . Might try on another diy tent room . Should be great .