By David M. Fitzpatrick
Special Sections Writer
While insulation and good construction are key to keeping as much heat as possible inside your house in the winter, there is perhaps no bigger heat-leaker than your windows. If you have old windows in your home, replacing them could be the biggest key to saving money on heating costs — no matter how you heat your home.
The first step in replacing a window in your home is to determine the condition of the existing window. If the existing frame is rotting, you may have to use new-construction windows. This method requires tearing out the trim and frame of the existing window, and reframing the opening as necessary. The new window would be installed using the same methods as those used in new construction. If the existing windows are in relatively good shape, you will be able to use replacement windows. These are relatively easy for a handy homeowner to install, and usually leaving interior and exterior trim undisturbed. Often, you’ll have much less time with a big hole in your house.
Wood or Vinyl?
The first big decision is whether to get wood or vinyl windows. It’s a matter of taste and what you’re willing to spend.
Wood windows are often considered more attractive and wood is a great natural insulator. They may feature a maintenance-free clad exterior and a wood interior that can match woodwork in your home. Wood windows tend to be more expensive, as the production is more complex. Custom sizes will take some time and cost more. “Wood is good,” but it requires more maintenance to prevent rotting, such as regular staining.
Vinyl windows are manufactured in an extrusion process, where melted plastic is pushed through a die, coming out cooled in the needed shape. This is quicker, easier and cheaper to produce than wood windows. Custom sizes are easy for the manufacturer to produce, and so are not much more expensive. “Vinyl is final” because it requires virtually no maintenance. It will not rot, will last a long time and needs no staining. The flip side: generally it is only available in white or beige.
The Big Energy-Savings Factor
After proper installation and sealing to prevent heat leakage, this is the most important factor to consider when you put in new windows. Windows bleed heat, but the type of glass you choose can greatly improve insulation and reduce energy loss.
Clear insulated glass is the least expensive. It typically offers an insulating value of R-2.
Low-E insulated glass is coated with a microscopically thin layer of metal that acts as a selective filter. In Maine’s climate, it helps keep heat in when it’s cold outside and helps keep heat out when it’s hot outside. It also reduces conductive heat loss, which is how heat naturally goes to colder areas. It typically offers an insulating value of R-3.
Gas-filled low-E insulated glass has gas — usually argon — between double panes, further reducing the conductive heat process. There have been other with different gases, but in terms of cost benefit, argon low-E is the way to go. R-value is about R-3.
Most windows sold in Maine use some type of low-E glass, as it is the best option for our climate. While clear insulated glass windows might save you a few bucks, you’ll quickly make the difference up in heat loss. Sure, R-2 and R-3 don’t sound much different, but every little bit of energy savings counts.
Don’t Let Your Energy Savings
Fly… Out the Window!
Weather-stripping. Even with the best glass in the best windows, poor weather-stripping can make it just as bad as if you had a big hole in place of the window. Most manufacturers make windows very tight, so this shouldn’t be a problem. Beware cheap windows with cheap weather-stripping, which can completely undermine your efforts to conserve heat.
Installation. A window should be caulked around the outside, and there should be some form of insulation around the inside of the window and the old frame. If that is done well, the installation should be as tight as a new construction window.
DIYers. While a replacement window is fairly easy to install, consider hiring a professional if you’ve never done it. Your dealer sales representative should be able to recommend several contractors with whom they are familiar and who have proven track records.
Trim. If you need to do any damage to the trim, inside or out, while installing a troublesome window, you may need replacement trim.