conserving homes will be more comfortable as explained in the next paragraph, and will have lower heating and cooling costs. Our Insulation Manual for ... I have assumed a design temperature difference of 70 degrees and all savings are quoted for these design conditions. ... area whose dimensions are 24 x 66V2 feet (assuming R-11 wall insulation). Reducing the ... A 24 x 50 ft. house with a 20 x 20 ft.