Lifestyle Energy - Heat Loss Calculator

Ceilings	Enter the area and R value for each ceiling area in the house that is exposed to outside temperatures.
Ceilings	Area	Rvalue	UA (BTU/hr-F)	Design Loss (BTU/hr)	Yearly Heat Loss (BTU/yr)
Ceiling 1
Ceiling 2
Ceiling 3
Ceiling 4
Walls	Enter the area and R value for each wall area in the house that is exposed to outside temperatures.
Wall segment	Area	Rvalue	UA (BTU/hr-F)	Design Loss (BTU/hr)	Yearly Heat Loss (BTU/yr)
wall 1
wall 2
wall 3
wall 4
Windows	Enter the area and R value for each group of windows having the same R value.
Window Group	Area	Rvalue	UA (BTU/hr-F)	Design Loss (BTU/hr)	Yearly Heat Loss (BTU/yr)
Group 1
Group 2
Group 3
Group 4
Floors -- Wood Joist Type		Enter the area and R value for each floor area in the house that is exposed to outside temperatures.
Floor segment	Area	Rvalue	UA (BTU/hr-F)	Design Loss (BTU/hr)	Yearly Heat Loss (BTU/yr)
Floor 1
Floor 2
Floor 3
Floor 4
Slab on Grade Floor		Heat loss from slab on grade floors is primarily dependant on the length of the perimeter and not the area of the floor. Rvalue here is the effective R value per foot of perimeter
Slab segment	Perimeter (ft)	Rvalue per ft of perimeter (1)	UA (BTU/hr-F)	Design Loss (BTU/hr)	Yearly Heat Loss (BTU/yr)
Full Slab
Infiltration	House Volume: is the total volume of the heated space of the house cubic feet (floor area times the ceiling height) Air Changes Per Hour: 0.33 -- very tight -- minimum for health 0.5 -- tight -- new, careful construction 1.0 -- leaky -- typical existing construction??
	House Volume	Air Changes per hour	UA (BTU/hr-F)	Design Loss (BTU/hr)	Yearly Heat Loss (BTU/yr)
Whole House
Internal Heat Gains		These are heat gains from warm bodies, lights, appliances, ... These heat gains will be subtracted from the total heat loss for the house. If you don't want to account for internal heat gains, enter 0 for the number of occupants More ...
	Number of Occupants		Internal Gains (BTU/hr)	Design Loss (BTU/hr)	Yearly Heat Loss (BTU/yr)