I am not a contractor...I obtained for an art project...Not what I thought. I expected a thick plastic-type material. It is made of a very thin styro-foam material. Now this may be acceptable as a ceiling tile which is it's original purpose.  The label says you can paint them...I just can't imagine these being glued to a ceiling, BUT, AGAIN, I'm NOT a contractor!!! They are fly-weight and super delicate!!!