Ask the Architect

Are triple-pane windows worth it?

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Q. We’re planning to replace our old windows, and are doing research online to make sure we make the right decision. I saw that there’s an option for “triple pane” windows instead of double panes. It appears to be much more money, but the writer of one article says it’s well worth it. Are you familiar with triple panes, do we need permits to change our windows and is it worth the expense? We’ve lived in our current home for five years and plan to be here for the rest of our lives, hopefully a long time, while we raise our family. What do you think?

A. I could simply say that you get what you pay for, but I’m certain you need more of an explanation, since you’ve taken the time to investigate and educate yourself. In your investigation, I’m sure you saw engineering data, lots of comparative numbers and U-values, the rating acronym for glass unit values. The lower the U-value, the better the insulating value of the glass.
Because the majority of heat or cool transmission or loss of energy is through the windows, while the walls, floor and roof are more insulated, it’s most important to do something to prevent losing all that energy you’re paying to create. Whether it’s your air conditioning or your heat, the outside of your house, referred to simply as the “envelope,” is of critical importance to insulate, especially with ever-rising energy prices. While most building departments don’t require a permit for changing out the windows “in kind,” meaning in the same size and location, some will require a permit for any little thing, like sanding your floors or adding closets, and I’m not kidding, so it’s best to check their rules online, or call your local building department directly.
Another thing to be aware of is that changing windows can trigger fire safety escape rules, referred to as egress windows, and most up-and-down, or double-hung colonial windows don’t meet the requirement if you don’t have at least one window in every habitable room with a size of 5.7 square feet. The window must have a clear escape opening of 20 inches in width and a minimum height of clear opening of 24 inches. Remember that a large fire rescuer must be able to save you.
Triple pane is a great value, because you’re always losing costly energy, so the return on investment, especially if this is your long-term home, makes it well worth it. Windows lose the most energy at the edges, so the type of gasket joining the windows to the frame is critical. The most effective frames have insulation blocking, not just a thermal break in the frame. A thermal break is usually a thin gasket between the outside and inside frames. Adding insulation, instead of leaving open air spaces in the frame, saves more energy, so it’s important to look for.

© 2022 Monte Leeper. Readers are encouraged to send questions to yourhousedr@aol.com, with “Herald question” in the subject line, or to Herald Homes, 2 Endo Blvd., Garden City, NY 11530, Attn: Monte Leeper, architect.