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HOW TO CHOOSE THE RIGHT WINDOW SIZE

On most windows installation projects that we work on, determining the replacement windows’ sizes merely requires an accurate measure of existing window openings. Our replacement windows are custom-built to fit the original openings, after all. Once in a while, though, a homeowner may want to resize their windows during remodeling. In these cases we often get asked if there are rules on choosing replacement window sizes.

How To Choose The Right Window Size

While there isn’t a one- and-done rule for this, the following guidelines may help you determine the appropriate window size.

Window Sill Height

The International Residential Code (IRC) states that sills on operable windows should be at least 24 inches from the floor. Ideally, you should be able to see out while sitting down on a chair or on the bed. If the design calls for a much lower sill, your choices will be limited to non-operable windows like picture windows or floor-to-ceiling windows.

Window Head Height

There aren’t rules governing how tall windows should be, and in many cases, it’s a subjective design choice. Too much space between the window head and the ceiling would result in less natural light – not an ideal design if you’re planning on buying energy-efficient windows. That is, unless you’re planning on installing clerestory window to complement them. Too little space leaves little room for window treatments.

Width-to-Height Proportion

Coming up with the width in relation to height is another subjective design choice, and sometimes the architectural style comes into play. For instance, continuous windows are common in modern architecture but would look out of place in traditional architecture. Grilles can also be a factor on traditional windows: grilles that are taller than they are wide generally are best, especially on wide windows.

Once you have selected the right window proportion, keep it consistent across all windows in the house for a cohesive look; inconsistent window sizes are not easy on the eyes. If you’re unfamiliar with building codes, our expert consultants are well-versed with it and will tell you if your design is compliant. Set your expectations early on that the window design won’t be exactly the same as you planned it once these factors are applied.

Renewal by Andersen® of St. Louis serves St Charles, MO and nearby areas. If you need help with finding the right window sizes or styles such as casement windows, call us today at (314) 310-3636 or fill out our contact form to schedule a free in-home consultation with our expert consultants.

Reviews

"Renewal was fantastic! They kept you in the loop from ordering to installation. They informed you at every step of the process of what was happening. The installers were kind, courteous, and professional. Everything was cleaned up after the installation. It was as if they hadn't been there except to see your beautiful new windows. I highly recommend them."

Angie Klevorn
Nov 21, 2023

"3rd time using RBA for window replacement. Again, a very positive experience, the windows are great, the installation was done right, the professionalism was apparent from start to finish. Still have existing windows to be replaced and will definitely use RBA again to do it in the future."

Doug Dick
Nov 21, 2023

"Renewal by Andersen was a good experience for us in replacement of our windows. From the initial meeting with the sales representative, Leslie, through the waiting period for manufacturing, and then to the installment process, our experience was excellent! Communication is key for me and we were kept informed and updated as our windows were being ordered and manufactured. Calls to update us on the installation process were welcomed and appreciated. They know how much is too much so they don't pester you with unnecessary contact. We love our new windows!!! Did I say that already??😂 We can tell a major difference in reduced Street noise and also the temperature at our windows. Excellent company, highly recommend!!"

Paula Null
Nov 15, 2023

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