Fiberglass window frames have advantages over wooden frames such as being resistant to changes, leaks, and warping over time. They are also easy to install as the frames remain square and level without additional reinforcement. Fiberglass is also a good insulator, making windows with fiberglass frames energy efficient. Common window types include double hung and side hung, with double hung traditionally being timber but also available in aluminum, and side hung generally being made of timber as well.

1. changes, meaning the won’t expand
or contract like wooden frames –
they also won’t leak or warp over
time.
They are easy to install – fiberglass
designs remain square and level
without the need for metal
reinforcement
Fiberglass window frames are good
thermal insulators, so they are
energy efficient.

2. Double hung
•Traditionally timber - western red cedar or hardwood, but also available in aluminium
•Usually purpose made
•Counterbalancing systems, including lead weights and spiral friction balances
•Insect screens fitted on the outside
•Some roll-up screens fitted inside
Side hung
•Generally timber - western red cedar or seasoned hardwood
•Stay-openers may be used
•Insect screens fitted on the inside