[ajg93]

Hube...I do have both supply and returns vents in the basement (2 supply, one return). Would increasing the return size help? I have kept the fan ON in low speed to not much help. As I said, the main floor is keeping all the heat. Both my upstairs and downstairs are cooler. I do think part of the reason stems for an improperly designed system - I just wish I new what was improper about it and what i can do to fix it. It just seems strange that all the hot air is being trapped on the main floor. The house is only 1500 sq ft (not including the basement).

Kactuskid - where is the sill plate cavity? As the previous owners finsihed the basement, I am sure there is nothing I can do now but I am curious to know. Also, thanks for the link to the radiant heating. Do you know of any contact for Canada?

Thanks for the help