A Critical Choice When Replacing Your Windows

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You’ve likely seen the ads for $100 window replacement. Most window replacement companies will sell homeowners windows based on price, and price alone. This can be incredibly tempting. However, if you’ve ever heard the horror stories of structural rot around windows, you can appreciate that more information is needed when deciding on new windows for your home.

The most important factor is this -

When replacing the windows in your home, your contractor should offer a choice between replacement windows and new construction windows.


This is a critical choice, and being armed with information will help you decide.


Replacement Windows


Replacement windows are an economical choice for some situations, however it is important to know-

Replacement windows are only a good choice when replacing very old wood windows that were often built into the walls of homes or into straight masonry openings.

In this situation, removing the window frames is not practical so the window sashes are removed, and the new window and frame are installed inside of the old frame. The important thing to realize with this method is that the condition of the existing window frame, flashing, and caulk will play a critical role in the overall performance of the window.

If these elements are allowing water intrusion, simply putting in a replacement windows will not solve the problem, despite what some window replacement contractors will tell you.

The reason this method is used so often is because it is easier and does not involve disturbing the interior trim.



New Construction Windows


New Construction Windows will cost more up front, but can save thousands of dollars down the road.

The best way to assure that your new windows will perform well and not leak is to completely remove the old ones, frame and all.

This would be the case when using new construction windows. This allows the opening to be inspected and prepared properly to prevent water intrusion into the wall cavity. This includes installing a sloping sill pan before the window is installed. The window’s nailing flanges can be integrated into the water resistive barrier of the house after window is installed. In this method, the window is completely weatherproofed before exterior trim and siding are installed.

Proper Sill Pan Preparation
Proper preparation of sill pan for window replacement

Trim and siding should never be used as flashing.


Trim and siding are there to protect the underlying water resistive barrier from UV rays that will break it down.

The new construction window replacement method is more expensive but much more reliable. While it may be tempting to go with the less expensive option now, remember -

Water damage caused by window opening issues not corrected when using replacement windows is exponentially more expensive to repair than it would have cost to do it the right way to begin with.

Replacement Window Caused Rot
Rot caused by installation of Replacement Window where New Construction Window should have been used.

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