Just talked to my DH about your question. He said it probably wouldn't be a good idea. The rolled roofing is treated with asphalt or tar. When it heats up, the tar starts bleeding through and smells. Plus, if you put the glider on top of it, it could possibly tear the roofing material.

I think it would be better if you used a piece of rolled vinyl. You can paint on the back of it and it works great! I've made several floorcloths out of it, and I feel it actually works better than the floor cloth canvas you can buy in a tube. The vinyl is smoother, and allows you to have sharper lines. Plus, I think it would withstand the elements without falling apart. Except extreme colds, which will cause the vinyl to get brittle.

Hope this helps.

I have the glider on top of some of this stuff now. I also have two concrete blocks with concrete pavers lying on top to make two endtables. Neither of those items have torn or did any damage to the rolled roofing. I put it down about a month ago. No smell either.

I haven't tried my idea yet. I will eventually and will most likely prime the whole thing first. I'm just going to try it outside.