Consider an old house(1858) constructed of 2-in hardwood planks plus 1/2 in of lapped wood siding, sheetrock(1/2 in) covers the inside of the dwelling. The size of the house is 28ftx40ftx10ft. For simplicity, assume the roof is flat, covered with 1-in plywood plus asbestos shingles and has 3 1/2 in of fiberglass insulation. There is a wood subfloor (25/32 in) in the attic and a ahrdwood floor (3/4 in over an unheated crawl space. Assume 25% of the wall areas are single paned windows. The outside is 40oF colder than the inside.
a)Now, consider only conductive heat losses, calculate the heating needs in Btu/h
b) what will be the percent savings in heating needs of this house is insulated with a total of 6-in of fiberglass in the attic
c) What will be the percent savings in heating needs be if this house is insulated with 3 1/2 in of fiberglass in the walls (ceiling is 3 1/2 in of insulation)
d)What percentage savings is achieved by replacing single pane windows with double paned windows (1/2 in in airspace)