Your windows bring air, light and warmth to your home, but they also let in cold or hot outside air, making your home less energy efficient and more expensive. If you’re thinking about investing in replacement windows for your Portland, OR home, you should take energy efficiency into account.
Energy efficient replacement windows can help reduce your energy costs and increase your comfort. In fact, they can pay for themselves in the long run through lowered cooling and heating costs. It’s important to remember, though, that not all windows are energy efficient. Construction, design and installation all effect energy efficient windows’ efficacy.
- Construction – Energy efficient windows lower energy costs by reducing solar heat transfer in the summer, and increasing solar heating in the winter. These properties are measured in solar heat gain coefficients, or SHGCs, U-factors and visible transmittance, or VTs, respectively. High-quality energy efficient windows should have an SHGC of more than 0.6 for maximum solar heat gain during the colder months, a high VT for more visible light transfer during the day, and a U-factor of less than 0.35 to lower conductive heat transfer. These effective benefits are from special construction properties like energy efficient window glazing, tinted glass, reflective coatings, and gas fillers.
- Design – There are plenty of options when it comes to window design, and almost every design has both positive and negative attributes when it comes to energy efficiency. However, there are a few window designs that stand out for energy efficiency:
- Casement – Casement windows are hinged at the sides. They typically have low air leakage rates because their sashes press against the frame while closes.
- Awning – Awning windows open out and are hinged at the top. Similarly to casement windows, they prevent air leakage because their sashes press against the frame while closed.
- Fixed – Fixed windows don’t open, making them very efficient in terms of air leakage and drafts.
- Double and Single Hung – Double and single hung windows have sashes that slide up and down to close or open the window.
- Hopper – Hopper energy efficient windows open inward and have lower air leakage rates.
- Double and Single Sliding – These windows have sashes that move horizontally to close or open. They have higher air leakage rates, but do offer good insulation.
- Installation – It won’t matter if you pick the highest quality windows with ideal construction and design if they aren’t installed properly. Always hire a professional to install your new windows to ensure an ideal installation, and be sure to have your professional install your new windows according to the manufacturer’s specifications. Double check your energy efficient windows for air seals, and, if necessary, install weather-stripping or caulk the window frame to form a tighter seal.