We recently raised the roof of the family room , creating a 2 story great room with a wall of windows.HVAC is an older 2 stage heat pump. It is a vacation home, not used as much in the winter. The family room has a wood burning fireplace.
Just heard from the builder:
"I met with our contractor yesterday. We talked about the new volume incurred with the addition. A heat load study was performed and we offer the following for your consideration.
* The existing system is 3-ton
* The load calculations on the entire home including modifications would require a 4-ton system
* Our contractor suggested as a starting measure to increase the air to the living room by enlarging the existing floor vents and boots from 2”x12” to 4”x12” in three locations. Then go through a winter and see how things feel. Other options to then consider would be adding electric baseboard heat or upgrade heating system. Since the glass wall is facing north, cooling may not be an issue. To enlarge the floor vents would cost $ XXX.00."
Is paying for larger ductwork and floor vents a better option than adding shunt valves in the ducts leading to other rooms? Is it more sensible to add portable electric heaters until we bite the bullet and replace the 20 year old heat pump. (maybe go geothermal, or propane backup heat pump)?Other ideas or comments? Thanks