Rot Doctor

[Miscellaneous Q&A Index]

Subject: Vertical 4 x 4 Post

Date: Friday, April 3, 2020


I came across your web site and am wondering if your products would be appropriate to repair a vertical 4x4 post. It appears to be rotting from the inside. The outer edge of the post still appears fairly intact; I only saw the rot in the middle when I climbed a ladder and happened to see it.



Used properly, our products can definitely be used to fix your post.

Typically, vertical posts rot at the top, and around ground level. It is a matter of how much moisture is getting to the wood. Rot at the top is fairly easy to fix, and very durable over time, as the top no longer absorbs moisture at the same rate. Rot at ground level can be repaired. But it is often more difficult, as the wood is usually wet, and more difficult to dry out. Additionally, if absorption from the moist ground is the issue, then fixing the rot should extend the life. Maybe 5–10 years. But, if chronic ground water is an issue, repair to rot in this location is not likely to prevent future rot.

If you rot is at the top, I would also check the post as it goes into the ground. If there is rot here too, you have to decide if it is better to fix or replace. We would be happy to consult with you via a phone call if you want to discuss this further.


[Miscellaneous Q&A Index]

Have questions?

Contact us by phone 206-364-2155 or e-mail (send us your pictures) at and we will gladly answer questions about our products or how to apply them. With 20+ years of experience and many more in the boating and construction industries, not much surprises us. We are here to help our customers solve their issues. Let us help you to not have any surprises in your repair project.

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The Rot Doctor, Inc.
P.O. Box 30612, Seattle, WA 98113
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