what to do about humidity when very cold

[macandchz]

i have my bp in a 40 gal. tank. temp varies from 79-82 degrees. the tank has a screen top that i cover with towels and a blanket. i have to spritz 3 times a day to keep humidity up. now that it is zero degrees outside, i have been keeping my house temp on 80 degrees to make sure mac is warm enough. i really feel bad to have to spray him 3 times a day bcause when i spritz him , the tank temp drops for awhile to 78.5. what is more important, the moisture or the heat? ihave a large heating pad attached under the tank and a small one by his hot side hidey tunnel. does my house temp affect the tank much? he does burrow under the bedding. does that mean he's cold? he hasn't been very active during this cold spell but does eat.