when too much insulation is a bad thing..
Gutted 1970's panel basement. Glued 2 inch rigid to concrete walls. R13 in joists above where foundation meets the walls. Framed and rock in front of that. Dricore subfloor. Also R13 in walls of laundry/mechanical area. the idea is that room can be cold while main basement area is warm.
1 month after installation my furnace shut down. Technician said it was a "pressure" code. checked hoses and pipes found no blocks. he thinks i made the room too airtight and it can't draw enough fresh air now (unit doesnt draw air from outside).
3 days ago my water heater stopped. error code was "vapor sensor" i know there was nothing in the area. in another forum a guy said the sensor trips sometimes because of bad air flow.
i didnt recall Holmes on Homes every saying too much insulation in the basement was a bad thing!