Hello, I have a hot water furnace that heats my tap water and house, and I replaced my heater covers with heavy duty polypropylene soffit, now I did some research, the furnace water never goes above 160F, the water registers never go above 100F, and the soffit is rated not to distort until a temp above 160-200F. Ever since I installed them, the home made soffit covers only get warm,never hot no matter how long the furnace is running, My question is, would this pass for a safe cover until I can afford store bought ones? Thank you..