Is there a difference what side goes up with fiber board insulation? I have a job that we are putting this down over old glue covered plywood and was wondering if it matters what side goes up. One side is dark and some what lumpy the other side is waffled but smooth.>>>
My understanding is that the black side (regardless of which side is smooth) goes on top with adhered systems. The asphalt coating acts as a binder and keeps the adhesive from just soaking into the wood fiber.>>>
Smooth side up if you are using adhesive or cold process (absorbtion) otherwise I don't think it really matters>>>
What kind of roof are you installing over the wood fiber? It does make a difference with some systems.>>>
the smooth side up,and it usually has some kind of print on the side that faces up-only that usually is the dark side,and the down side looks dimpled>>>
We always put the dark side up. Pretty sure that's the right way.>>>