Energy Efficancy Of A Home Flashcards
What is the equation for payback time?
Initial cost
Payback time= ————–
Annual saving
What is the pay back time for loft insulation in the entail cost is £200 and annual saving is £50
4 years
What are the most effective methods of instillation?
The ones who have the biggest annual saving
What is the definition of payback time
The money you have saved on heating bills will entail cost of installing eventually the time it takes is the payback time
The ones with short payback times tend to be…
The most cost effective
What does cavity wall installation stop?
The bricks reduce convection and radiation across the gap
The foam stops conduction
What does loft insulation stop?
Conduction and convection
What does draught proofing stop?
The loss of convection
What does a hot water tank stop?
Lagging and fibre glass wool reduces conduction and radiation
What does thick curtains stop?
Conduction
Radiation
What do u-values show?
How fast Heat can transfer through materials
So does a better insulator have a high or low U-value?
Lower
Are effectiveness and cost effectiveness the same thing?
No
