Insulation Products

[Lostranger]

I like rigid polyisocyanurate foam with foil on both sides. I seal gaps and cracks with — wait for it — Great Stuff Gaps and Cracks.

My research indicates that polyiso board has the highest R value of anything readily available. Considerably better than any color of styrene board. Impervious to moisture. Does not lose R capability over time. No chance of heat buckling outside panels.

My only problem is that it is hard to find where we live other than in 1/2" thickness. I'm getting ready to order a full unit of 1-1/2" boards from a local building supply. Don't need that much for the Gillig, but I think I can sell the balance on Craig's.

I'm using 1-1/2" in ceiling and most wall space. Floor and balance of wall area get 1". Planning to double the locally available 1/2" where I need 1".

To install 1" of any kind of foam, strips of 5/4" treated decking make great furring. I saw nominal 6" boards into three equal strips.

Used this system for ten years in our Flx Metro. That bus had many problems, but lack of insulation was not on the list.

[Oonrahnjay]

I like rigid polyisocyanurate foam with foil on both sides. ...

    Sound good Jim.   Seems to be hard to find near me - do you have a "trade name" or brand on this?

[Seangie]

Bruce -  They sell it at homedepot in Wilmington...at least they did when I was there.  Its foiled on both sides and says RMAX on it...I think.  They only had 1/2 inch but I tripled in areas that I needed to fill and it worked great.  Most of my bus's outer steel framed walls had the 1.5" already in them and I added another 3/4 of the blue board on top of that.

-Sean

[Lostranger]

    Seems to be hard to find near me - do you have a "trade name" or brand on this?

Bruce, the half inch stuff Lowe's sells here is called R Max. Year before last I ordered 17 sheets of 1-1/2" to do our step van. It was Dow brand. Don't remember the trade name, but it was also something that ended in max. Same lumber yard can no longer order partial units.

I'm also putting a layer of foil bubble wrap inside everywhere.

[Oonrahnjay]

Bruce, the half inch stuff Lowe's sells here is called R Max. Year before last I ordered 17 sheets of 1-1/2" to do our step van. It was Dow brand. Don't remember the trade name, but it was also something that ended in max. Same lumber yard can no longer order partial units.

I'm also putting a layer of foil bubble wrap inside everywhere.

     Thanks, Jim and Sean!  I'll look!