A house built in the 1950s has a single-glazed window that is 250 cm x 120...

 

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A house built in the 1950s has a single-glazed window that is 250 cm x 120 cm in size. The owner wants to replace it with something more energy efficient. The owner has been given a quote of about £700 for double glazing and a second quote, at 50% more, for triple glazing. i.Calculate the rate of heat loss in watts for the current single-glazed window on a cold winter's day in December when the outside temperature is 2.0°C and the room internal temperature is maintained at 21.0°C. Take the U-value of the window to be. 4.8 W m² K¹ Give your answer to an appropriate number of significant figures. ii. How much heat in kilowatt-hours will be lost over 24 hours if the average internal and external temperatures remain the same throughout the day? A house built in the 1950s has a single-glazed window that is 250 cm x 120 cm in size. The owner wants to replace it with something more energy efficient. The owner has been given a quote of about £700 for double glazing and a second quote, at 50% more, for triple glazing. i.Calculate the rate of heat loss in watts for the current single-glazed window on a cold winter's day in December when the outside temperature is 2.0°C and the room internal temperature is maintained at 21.0°C. Take the U-value of the window to be. 4.8 W m² K¹ Give your answer to an appropriate number of significant figures. ii. How much heat in kilowatt-hours will be lost over 24 hours if the average internal and external temperatures remain the same throughout the day?

Answer rating: 100% (QA)

i To calculate the rate of heat loss for the current singleglazed window we can use the formula Heat ... View the full answer