What’s the best strategy for saving energy in my unconditioned attic?
I’m in zone 5A and have 6″ of insulation between the floor joists and no insulation between the roof rafters. The HVAC system and all its flex duct work are in the unconditioned attic. The building is a town house with 40″ common walls running east west and the 18″ roof ridge running north to south. There is eaves and ridge venting. The roof rafters are irregularly shaped: some are standard widths, others are not.
The HVAC unit and flex duct work are in the attic, in the unconditioned space that is bitter cold when it’s bitter cold out, and roasting hot even on moderately warm sunny days from late spring to early fall.
Is it better to focus on reflective material or insulation in the roof, or more insulation on the floor to reduce the HVAC run time in the conditioned on the two floors below?
I have a ventilated crawl space under the house. The joists are insulated with original (30 year old material. The exposed concert walls have rigid insulation. In the winter the floor above the crawl space is cold, and drafty in some spots.
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