The walls of your bedroom have an r value of 13 f sq. ft. hr/btu. your bedroom is 13 feet long and 12 feet wide with walls that are 8 ft high. on a particular day the average outside temperature is 25 degrees f. how much heat is lost through the walls by conduction on that day (in btus)?

To solve this problem we will apply the concept of heat transfer and conduction depending on the Area, the temperature change and the thermal resistance, this can be expressed as

Where,

A = Surface Area

HDD=Heating Degree Day

R = Thermal Resistance

According to the information the Area of the wall can be calculated with the given dimensions

Heating Degree Day would be

Finally the heat transferred is

Therefore the heat that is lost through the walls by conduction on that day is 29538.46BTUs