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Factors That Affect Replacement Window Sizes

Choosing the right windows for your home remodeling project involves many considerations. Much has been said about choosing the right materials, hardware and energy-efficient features, but a less-discussed aspect involves window sizes. Let’s look at the factors that affect the choice of replacement window sizes.

 

Factors That Affect Replacement Window Sizes

Wall Openings

Building codes notwithstanding, window replacement projects generally don’t involve expanding the wall openings. Most new construction windows are built as part of the wall framing; therefore, expanding the wall opening may incur additional costs because the wall framing will have to be rebuilt. There is also the risk of damaging the siding or voiding its warranty coverage. There are exceptions, such as combining adjacent windows into a large window, since these smaller windows are built on a single wall opening.

Aesthetics

It’s always a good idea to sketch out what your new windows will look like before making your decision. Whether you choose to draw it by hand or by computer or through augmented-reality applications on a smartphone, make sure that you are happy with what it looks like on paper (or on screen) before you commit to it.

Sun Exposure

Natural light is an important factor when choosing window size; large windows will allow more light into your home. You have to consider whether letting direct sunlight into your home is something that you want as it could fade fabrics and furniture in your home, though low-emissivity coatings can help block unwanted ultraviolet (UV) rays and can make your home hotter. Consider the four principal directions:

East – East-facing windows lets you meet the sunrise every morning and gets you your daily dose of vitamin D. However, they may be too bright for people who prefer to sleep in during weekends.

West – West-facing windows provide a great sunset view, which is why large picture windows are often installed on the west wall.

South – The natural light that comes through south-facing windows tends to be harsh, but can be useful in large rooms or in areas with open floor plans.

North-facing windows provide the most balanced natural lighting throughout the day. Rooms with north-facing walls can benefit from large windows.

If you need further guidance with choosing the right window sizes, our consultants can help you with your choice.

Renewal by Andersen® of St. Louis is your leading provider of replacement windows and patio doors. Give us a call at (314) 983-9977, or fill out our contact form. We serve customers in St. Louis, MO, and nearby areas.

Reviews

"Have nothing but great things to say about the window installation done today by John Hutchinson with Renewal by Andersen! He was friendly, personable and professional and did a great job installing. He did a great job of putting down roller pads and tarps with next to zero clean up. Would highly recommend them for any window replacement needed!"

Mark V.
Jun 26, 2025

"We had our new Renewal by Andersen windows installed on June 5th & 6th, 2025 and we LOVE them! The quality, beauty, and functionality are best-in-class! The whole experience from dinner presentation at Lazy River Grill, the initial in-home sales consultation and measurement, the regular communications from the salesman and concierge, and the installation team’s professionalism and skills made the process so seamless. This is the second home we have opted for Renewal windows and doors and have been delighted both times! Thank you Renewal by Andersen STL! "

Jeff C.
Jun 7, 2025

"I had an excellent experience with RbA STL. Our designer, Courtney, was great and the finished product is awesome. The installation was easy and the gentlemen left our home cleaner than they found it upon entering. I would recommend RbA STL - you’ll get tired from their constant contacts, and that’s a GOOD thing!"

Jeramy D
Jun 3, 2025

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