Space Between Fireplace and Wall
There is some space between the back of my fireplace and the interior wall. The gaps (on each side)are covered with moulding, but I can feel air coming into the house through these gaps and would like to seal them. Do I need to use mortar to do this, or would the canned foam insulation that you can get from places like Lowes or Home Depot be good for fixing this problem? Is there a danger that this foam will ignite from the heat generated by a fire in the fireplace? Also would a chimney balloon or chimney pillow possibly solve this problem?