Cement door sill
I am replacing my old front door with a prehung steel door. Currently I have a concrete sill which wraps right from the inside of the door to the outside and around the brick. In winter, this sill is a fantastic transferrer of heat, and I always wind up with condensation and mould on the inside edge of the sill. It looks like a massive undertaking to replace the whole sill, and my new door frame and sill will fit into the opening with merely grinding down the 'hump' on the cement sill. My best idea at the moment is to cut a trench in the cement sill underneath where the new wood/aluminium sill will rest and fill it with spray insulation as a thermal break. Just wondering if there is another common solution to this, and looking for thoughts and opinions on my plan.