By Jim Price


I live in a circa 1950’s house that has forced air heating. Additions and have been made with better envelope performance therefore increasing the furnace heating output has never been required. After remodeling our kitchen and extending in to the former dining room we installed a ceramic tile floor. It can feel cold in the mornings and most of the winter because I don’t let the thermostat to go higher than 68° and the basement is un‑heated.

Existing Conditions

Our house is heated with a two‑stage condensing gas furnace.  Years ago the highstage stopped working and the low‑stage 40 MBH was always enough to heat our house.  (less than 20 Btu/sqft-hr).  Our domestic water is heated with a direct vent hot water tank style heater.   The total input capacity is 24 MBH.  This is more than adequate if we schedule things wisely.