1) Hydro One Networks, Energy Efficiency Tips & Tools, http://www.hydroonenetworks.com/en/efficiency/windows_walls/caulking_weatherstriping/cheap_tips.asp

2) Canada Mortgage and Housing Corporation, The ABCs of Windows, http://www.cmhc-schl.gc.ca/en/co/renoho/refash/refash_021.cfm

3) Natural Resources Canada, Consumer’s Guide to Buying Energy-Efficient Windows and Doors, http://oee.nrcan.gc.ca/publications/infosource/pub/renovate/Consumers_Guide_EE_Windows_Section07.cfm?attr=4#design

4) Canada Mortgage and Housing Corporation, Understanding Window Terminology, http://www.cmhc-schl.gc.ca/en/co/renoho/refash/refash_022.cfm

5) Natural Resources Canada, Consumer’s Guide to Buying Energy-Efficient Windows and Doors, http://oee.nrcan.gc.ca/publications/infosource/pub/renovate/Consumers_Guide_EE_Windows_Section07.cfm?attr=4#design

6) Natural Resources Canada, Windows, Doors & Skylights, http://www.oee.nrcan.gc.ca/residential/personal/windows-doors.cfm?attr=4