ID this polyiso?
![](https://secure.gravatar.com/avatar/f7cb174131f4b8d299ff0e3df9b44e6c?s=52&d=https%3A%2F%2Fimages.greenbuildingadvisor.com%2Fapp%2Favatars%2F200x200%2Ft.png&r=g)
It looks and feels like the facings of this unlabeled, salvaged polyiso are paper, but I’m told they might be fiberglass. Does anyone know for sure? I’m wanting to glue radiant barrier to one of the facings, and I need advice about what kind of roll-on glue to use and whether to use ordinary aluminum foil or a different radiant barrier product. I’ve never seen a self-adhesive radiant barrier, but if you have, I’m interested in that too.
GBA Detail Library
A collection of one thousand construction details organized by climate and house part
![](https://www.greenbuildingadvisor.com/app/themes/greenbuildingadvisor/dist/img/modules/detail-library/thumb1.png)
![](https://www.greenbuildingadvisor.com/app/themes/greenbuildingadvisor/dist/img/modules/detail-library/thumb2.png)
Replies
I have no advice on your radiant barrier question, but I just worked with the identical product. It's roofing polyiso, fiber faced, a cardboard like paper as well as some fiberglass. Basically like cereal box cardboard but itchy from glass.
Yeah, I figured it was roofing polyiso. Any idea why they mix paper with fiberglass?