The glass transition temperature (Tg) which is the temperature at which most epoxies will start to soften is about 325-350. You can always take a few temp readings in the area of concern with an IR gun if you have any question as to what the actual temperature is, I doubt it is that high. The PO probably used a contact adhesive which will soften in any heat. I found that by putting an extra layer in insulation under the dog house greatly reduced the heat at well as noise. I used to get "hot foot" now I can drive barefoot with no problem.