What are the Signs of Window Wood Rot & How Do I Repair It?

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At Perfect Windows, Doors, and Siding, we are committed to delivering high-quality, energy-efficient, and lifetime-guaranteed windows, doors, and siding with a promise of “perfection engineered for your home.” Today, we want to shed light on a common issue that many homeowners face – wood rot in windows. It’s a problem that might not always be obvious, but its consequences can be costly if left unaddressed. In this article, we will explore the signs of window wood rot and provide guidance on how to repair it effectively.

The Deceptive Nature of Paint

You might have heard people say that wood rot started becoming prevalent when lead was removed from paint. However, this is a misconception. Paint can actually conceal wood rot. Modern wood used in homes today is vastly different from the old, durable wood of the past. The paint on the exterior of your home might give the illusion of strength, but it’s merely a protective skin.

When you touch painted wood that is affected by rot, it can feel soft and unstable underneath. This is because newer wood, like the fast-growing soft Pine commonly used today, is not as resilient as its older counterparts. It lacks proper treatment and durability, making it more susceptible to rot. To detect wood rot, you’ll need to go beyond appearances and feel for softness.

Indications of Wood Rot: Focus on Corners

The weakest part of lumber is where it has been cut, and the fibers are exposed. These exposed fibers act like sponges, absorbing moisture and facilitating the rotting process. The telltale signs of wood rot often begin at these vulnerable corners. To check for wood rot, start by inspecting the corners of your windows, but remember, you’ll need to touch the wood to confirm if it’s solid or soft beneath the paint.

Where Water Sits, Rot Persists

Understanding where water collects is crucial in identifying potential wood rot issues. Water tends to settle in areas where it can’t escape easily. For instance, the top part of a window is a common spot for water to accumulate. Even though water doesn’t defy gravity, it can still lead to severe rot if it remains stagnant.

Sun exposure exacerbates this problem, particularly for southern and western facing windows with wooden frames. The sun’s relentless rays can deteriorate wood, making it more susceptible to moisture damage. As wood expands and contracts due to temperature fluctuations, the fibers open up, allowing moisture to infiltrate, further worsening the rot.

Temporary Solutions: The Pitfalls of Hiding Wood Rot

Many painters and homeowners resort to temporary solutions when they encounter wood rot. They may bond or fill in the affected areas to mask the problem temporarily. However, these are merely Band-Aid solutions. Over time, the wood will continue to contract and expand due to environmental conditions, causing the caulking or Bondo to separate.

If you’ve ever applied such quick fixes, you’ve likely noticed that the wood rot reappears within a year or two, often spreading beyond the original patch. These temporary solutions might seem cost-effective initially, but they can lead to ongoing expenses and frustration.

Repair vs. Replace: A Long-Term Perspective

When dealing with window wood rot, you have two main options: repair or replace. Repairing wood rot can be a more affordable choice in the short term. Products like Bondo and various chemical compounds can be used to patch the damaged areas. However, keep in mind that these are still temporary fixes, akin to patching a flat tire. Eventually, the issue will resurface, necessitating further repairs.

The alternative, which may seem more costly upfront, is to replace the affected window entirely. While window replacement does require an initial investment, it is often the more economical solution in the long run. Constantly patching and repairing wood rot can accumulate expenses over time, making window replacement a more sustainable choice for homeowners concerned about their budgets and long-term durability.


In conclusion, wood rot in windows is a common problem that can lead to significant structural issues if left untreated. While the signs of wood rot may not always be immediately obvious, identifying and addressing them promptly is essential. Temporary solutions can offer short-term relief but may prove costly in the long run.

Therefore, for a more enduring solution, consider window replacement. If you suspect wood rot in your windows, don’t hesitate to contact us at Perfect Windows, Doors, and Siding for expert guidance and assistance. Our commitment is to provide you with the perfect solution for your home, engineered to last a lifetime.