I have a question I have been struggling with. First a little background info:
Last September I purchased a 2 story Cape. The place is an energy hog (insulation reasons). I live in Maine and we heat using oil. The house was a prefab. When the original owner bought it the downstairs was finished but he finished the upstairs. During the winter we found it was cold upstairs but the downstairs was a nice temp. The conclusion I came to was the attic was not insulated--we didn't know since there was no attic entrance. We went out and bought two programmable thermostats, one for each floor/zone. During the day the programmable thermostats drop the temp in the house to 62 degrees. When we get home at 5pm the downstairs heats to 70 degrees and the upstairs stays at 62 until we are about to go to bed then heats to 68. Recently I got into the attic to find there was no insulation in the attic and side attics. I have since added about 15" of insulation for an R value of about 52 into the attic.
OK, now my question, since the upstairs is only the bedrooms and we are only up there in the evenings would it be cheaper to keep the upstairs at 62 degrees even when the downstairs is 70 degrees or should I try to keep the two zone temps closer?
Sorry for the long post. I'm just trying to save money with oil prices and all. Thanks ahead of time for any insight given