By Steve Graham, Networx
New energy-efficient windows may be a good investment in some cases, but oddly shaped windows require custom replacements, which quickly get prohibitively expensive.
Instead, upgrade existing oddly shaped windows to minimize the transfer of heat energy either through the glass or through cracks and gaps in the frame. While insulating shades and other energy-saving measures may not be an option for some oddly shaped windows, you can reinforce existing glass windows, and seal around the frames.
Repair, not replace
For several reasons, repairing old windows may be more eco-conscious than replacement.
• Older window frames were often made with denser hardwoods, making them more durable and insulating.
• New vinyl windows release toxic byproducts.
• Replacing windows involves all the energy used in creating the new windows, and the landfill space needed for the old windows.
Insulate the glass
Moreover, a well-sealed single-pane window fronted by a properly installed storm window can be more energy-efficient than new double- and triple-pane windows.
Both interior and exterior storm windows increase energy efficiency, but interior windows are easier to add and remove, and they are less likely to trap moisture. Unfortunately, pre-fabricated storm windows are unlikely to fit over oddly-shaped windows, and custom jobs can be expensive.
There is an easy DIY solution -- cut double- and triple-wall polycarbonate panels to fit your window opening and put them up each winter. BuildItSolar.com offers detailed instructions here. The panels are light and sturdy, but easy to cut and highly insulating. The only drawback of multi-wall polycarbonate panels, which are often used in greenhouses, is that they may distort the view because they have closely spaced ribs holding the panels together.