gelcoat

[KBbricker]

Does gelcoat offgas? if so, for how long?

[D'ARTOIS]

About quite some time. Minimum a fortnight. Can be in reality much longer.

[jimslade]

about two weeks. warm temp shortens the time

[yokebutt]

Bricker,

One of the main components of polyester is a volative chemical called styrene. Styrene is what's responsible for that characteristic "fiberglass smell" of poly- and vinylester composites. Most of the styrene becomes part of the cured laminate/coating, but some evaporates during and after applying it. So, the simple answer after this convoluted preface is; If it smells like styrene, it's offgassing.

I should also say that the base polyester resin in gelcoats, laminating resins, putties, etc. is pretty much the same thing. For you experts out there, yes, I know that this statement glosses over a lot of subtleties, but in this case I think it's good enough for government work.

Yoke.