. I did lay out my glass over a 60 degree sealed hull and then cranked on the heater to increase the heat to 85 degrees.

Ouch! There's your problem. Off gassing of the wood. Raise temperatures and the wood will off gas, raise temperatures fast and you'll have a lot of off gassing with foam!

Was the heater pointed near your hull?

I do not trust there will be no "off gassing" unless I have a cured seal coat AND fiberglass layer or a glassed (bare wood and fiberglass one shot) layer and one fill coat. One coat of epoxy or a wet-out layer of glass is NOT Airtight!

I used a forced kerosine heated for years without problem. You must have a good intake air source for the heater AND YOU to breath. Moisture produced by the heater is offset by dry winter air.

I had some spot lights that caused there own little areas of off gassing, until I wished up to that problem.

If you haven't experienced "off gassing" try coating a piece of wood with epoxy and put it under a spotlight. FOAM CITY!

Unless your shop temperatures are steady, or better, warm and dropping, you will experience off gassing to a greater, or lesser degree.

Check out my epoxy coatings/transparent lay-up page @

http://www.laughingloon.com/epoxy.html

I address ALL the possible issues discussed in this thread.

Good Luck
Rob