Salvaged Polyisocyanurate Insulation

Lo and Behold, Gooooooogle search!  I wanted some salvaged rigid foam insulation and I got it through Insulation Depot.  They were very easy to deal with and I would definitely buy from them again.

Try saying 3.5" foil face polyisocyanurate insulation three times fast (it's actually not as hard as I thought it might be).  Ohh! try just polyisocyanurate three times fast.

Anyways, poly-iso has the highest R-value, R-8 (R-esistance to heat flow) per inch of all common insulating materials.  So for every inch of insulation you'll stay that much warmer or cooler and use less energy.  Obviously this is very helpful in a small space where every inch counts.  When you leave a 3/4" gap between the foil face warm side of the insulatin and the heated space, you add on 2-3 more units of R-value, mostly because the radiant heat waves are being reflected back inward.  That means my wall will have an overall R-value of about R-30! and the roof around R-35.  This is well above the local building code and should keep me very cozy.  This can also be helpful in hot climates where you want the sun to bounce off instead of penetrating.  Again, you need an air gap for foil face to be effective.

Unfortunately, I felt a little cheated when I saw both sides of the insulation, after renting a U-haul and driving two hours to Charlotte.  Here's the photo they sent me of the insulation coming off the roof at the job site:


That was only one side, which in hindsight is quite obvious from the image.  There's also some cupping of the panels in that that foil side would hold a small puddle of water.  That won't cause a problem with my installation, but could be challenging for others.

Anyways, I'm still very happy with the product and the company.  I think they're doing something very worthy and necessary and I feel like I got a great deal of 30 3.5" sheets of poly-isocyanurate at $20 each.  I just looked up prices for new poly-iso at the big box and it goes for $10 for a 1/2 inch unfaced sheet.  Extrapolate, $70 new for my 3.5" foam, though probably only about $40-50.

Insulation Installation (another good tongue twister) hopefully coming fairly soon.