P1 - Home Insulation Flashcards
What is payback time?
The amount of time that it takes for the amount of money saved to equal the cost of the insulation
How do you calculate payback time?
Payback time (years) = initial cost / annual saving
What is a “cost-effective” method of insulation?
One that has a short payback time
Describe the 5 methods of home insulation
Draught proofing - strips of foam and plastic around doors and windows that stop heat loss by convection
Loft insulation - a thick layer of fibreglass wool laid out across the loft floor and ceiling reducing heat loss by conduction and convection
Cavity wall insulation - foam squirted into the gap between the bricks reduces convection, conduction and radiation through the gap
Thick curtains - create an air gap between the window and room stopping hot air reaching the glass by convection. Conduction is also reduced
Hot water tank jacket - fibreglass wool around hot water tanks reducing conduction and convection
What is U-value of a material?
A value that shows how fast heat can transfer through a material
The better the insulator, the lower the U-value
What is the unit of U-value?
Watts per square metre kelvin (W/m^2K)
What is an “effective” method of insulation?
One that gives you a large annual saving (they save you a lot of money each year)
