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How to Measure for Replacement Windows

Bay window with a cushioned area for reading in new home addition

Accurate Measurements Mean Better-Fitting, More Efficient Windows

Quality replacement windows can transform the look of your California home while improving its comfort and efficiency. If you are considering new windows for your home, it is important to measure the openings carefully for a precise, great-looking fit. Here are a few tips that can help you learn how to measure for replacement windows accurately:

Keep Track of Your Windows

A typical home in San Diego, Los Angeles or nearby areas has dozens of windows, and while there may be a few that are similar sizes, most will differ in size significantly. Plus, there will be several windows per room and multiple rooms to keep track of.

To record your window sizes accurately, you will need to develop a system to keep track of all the windows in each room of your home. A large notebook is ideal, with a page for each room’s north, west, east and south walls.

Sketch each wall, complete with a drawing of every window. Number each window and independently record the measurements for its width and height. Repeat the process for each room of your home.

Staying organized will help you measure each window correctly and avoid skipping any while planning to install new windows.

Measure Window Width

To determine the width of your replacement window, measure the existing window from the jamb on the left to the jamb on the right, just inside the frame. Do not include the trim that is outside the frame, installed on the interior wall. Take three measurements total — one near the top, one near the middle and one near the bottom — opening and closing the window sashes as necessary to place the measuring tape where it is needed. The smallest of these three measurements will be the width of the window.

Measure Window Height

For the window’s height, measure from the top of the frame to the bottom or sill where the window rests when it is closed. Again, leave out any trim installed around the window on the wall. Measure in three places: to the left, near the center and to the right. The smallest value will be the height of your window replacement.

Measure Window Thickness

Measure the depth or thickness of the window by opening the sash and measuring the depth of the frame, minus the width of any trim installed on the interior or exterior walls. For replacement windows in standard walls, the depth is usually not a concern. However, the depth may be important for unusual wall thicknesses, such as those in a motor home.

Check for Squareness

Measure from the top left of your window to the bottom right, then from the top right to the bottom left at similar points on the frame. If these measurements differ by more than 1/4 an inch, special framing may be required to adapt your opening for a standard home window replacement.

Window Installation & Replacement in San Diego & Las Angeles, CA

Once you have found the window sizes you need for your California home, talk to our team at OJ Insulation. We offer high-quality replacement windows at great prices, and we provide energy-efficient, professional window installations. Our experts can help you find the ideal windows for your home, and if you need advice about measuring windows or choosing window types, feel free to call our team today. We serve homeowners throughout California, and we specialize in home insulation services, gutters, window coverings and more.

Call (800) 707-9278 today or contact us online to order your replacement windows or request a quote!

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