Both rotting and mold in wood window frames are a result of moisture being allowed to come into contact with the material repeatedly for a prolonged period of time.

While rotting may be a result of a poorly functioning window, it is not always the sole cause of leaks. Often leaks in a house happen through openings in the wall structure or even the roof.

But regardless whether the source of the leak is in the window or in the structure, water damage to wood windows means one thing: the window is no longer performing as it should.

Remember, it is not always easy to recognize water damage in your window frames. While it may show up as leaks on the wall, a lot of times it is impossible to tell if the wall is damaged or moldy on the inside, until the window is taken out. 

And while to you it may not look like there is anything wrong with your windows, leaving rotten frames is a serious concern for several reasons.

  • If left untreated, rotten wood frames can begin to grow mold. Mold is not only bad for the structure, but also for occupants of the house and can lead to health problems.
  • Because rotting occurs when moisture is absorbed into the wood, it is possible for it to spread. On a long enough timeline, this rotting can affect not just the area around the windows.

What is the best solution for rotten wood frames?

If you haven’t done any research into replacement windows yet, there are two main types of window replacement: full-frame (tearout) or insert (retrofit).
In a retrofit replacement, windows get inserted into the existing frame. Your brickmould, jamb, and other window components remain intact.

With a full-frame replacement the window is taken out and components are removed down to the studs and header surrounding the window. New windows are then installed with new jambs, brickmoulds, and casings.

See the difference? Obviously, the logical conclusion is that retrofit window replacement is not advisable if you have any moisture damage or rotting in your wood frames.

Yet these type of installations happen in your city daily. Either through lies, or straight negligence, window companies often manage to convince customers that a retrofit installation is a sufficient solution for them. After all, it is easy to assume that there is nothing wrong inside of the wall, simply if you don’t open it.

Even if a retrofit window makes your home warmer in the immediate, it is simply a band-aid solution that will need to be properly rectified down the road. While most new windows have a warranty of up to 25 years. If there is any water damage or rotting in your frames, and you go the retrofit route, you may be looking at another window replacement project three to five years down the road.

This is something that shouldn’t ever happen. A retrofit vinyl window is being replaced just five years after it was installed, because of moisture damage in the wooden frame.


Although a full-frame replacement is a more expensive investment at the outset, it is still cheaper than doing replacing your windows twice.

In many ways, assessing the state of your home and recognizing the problems within the structure is a job for your project consultant, and the measuring installer. Window professionals can often recognize signs of rotting and let you know right away that a full-frame is the right choice.

Be more wary of project consultants trying to convince you otherwise. A lot of the time bad window companies just push cheap stock product to make a quick sale, without any regard for post installation service or how long the windows will actually last.

That’s where the responsibility lies with the customer. Do the research not only on the different companies, but also on the window installation process. By knowing the difference between different window components, types of installation, and window functions, you can do a fairly good assessment on the condition of your windows and frames, and decide exactly what is ideal for your replacement.

Learn everything you need to know about replacement windows:
Find out how much a window project should cost
See our full line of replacement vinyl windows
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At Ecoline Windows, we understand the importance of proper installation to the longevity and performance of your new windows. Although we do work with both retrofit and full-frame replacements, we prefer to specialize in full-replacement projects as we believe they are the most thorough and correct way to replace windows. Our professional window installers will expertly assist the condition of your windows and rectify any moisture or rotting problems at the time the window is removed. All our vinyl windows come with a vinyl brickmould, vinyl jamb, and casings to ensure your window performs for as long as possible and looks seamless on the inside and outside.