ORIGINAL: Augie11
For building you should be ok at those temperatures. Might have a problem painting though with some paints. And your epoxy will probably thicken up pretty good. The epoxy can be softened/thinned by carefully heating in a microwave for 10 or 15 seconds or hitting it with the heat gun.
Epoxy needs to be at 65 degrees min during cure for max strength. Heating for short amounts of time will also adversly affect the overall strength.