Roof Insulation Thickness

[Tas]

Hi All!

Pics to come however, I'm in the process of insulating my new 6x12x6'6" enclosed. Have done a lot of reading here and most everywhere. I've used 1" reflective insulation on the walls but should I use 1" or 2" on the roof? I've got room for 2" but have 3 pieces of 4x8 board left and didn't know if I could/should use that or go back and get 2".

What you all think?

Thanks in advance.

[MtnDon]

There is nothing wrong with using two layers of 1" to get a 2" total thickness. Even better if you can stagger any overlapping seams.

FYI, if there is no air space between the reflective foil face and the next solid layer, there is really no benefit from the reflective surface.

[onehoser]

i put 2 layers of 1" foil both sides in the ceiling of my 6x12

[Tas]

That's an idea too, 2 layers. I've getting tried of cutting all this stuff at the moment. I cannot cut a straight line to save my life!. OMG!

I put up 1" thick along 1 row and there is a big difference in surface temp of the aluminum skin and the insulation board with the 1" air gap. Tried taking the temp with my HF IR temperature gauge but the batteries were not good.

Makes sense about the air space so that's why I asked to get more thoughts on it.