We’re getting ready to paint and I was checking around my porch. There are three columns that support the roof over my porch. One of them had a decorative cross member that was dislodged because of dry rot at the location where the cross member was nailed to the column. I saw some dry rot there and started to excavate the rot. rot dim 1 rot dim 2 rot dim 3 can see concrete columns base

Here are some pictures of the bottom of the post. It has a small amount of concrete around the posts. The post goes into the concrete an inch or two deep.

What should I do about this. I think that since there are two others columns supporting the porch roof this one with the rotted base didn’t really affect the general load bearing aspect.

How should I fix this? Just add a lot of bondo, or wood filler, et.

Take the post out and put in a new one? (I don’t want to do this bc I would need to take out all he decorative cross beams.

Cut out the old wood base and graft on a nicer/new to replace the big sections that we cut out?

  • 2
    Hopefully you have checked the other posts (or will) for similar problems... Apr 14, 2019 at 14:10

3 Answers 3


Are you sure about the load bearing? It may sag if you are not careful...

Anyway either replace the post completely or make a replacement bottom section and support the rest of the structure - acrow jacks work well for this type of thing.

This is one example of a supplier of acrow jacks - many others... : https://www.scaffolding-direct.co.uk/new-size-3-acrow-prop-2-4m-4m/

  • Do you recommend bottle jacks(hydraulic) or screw jacks? While researching people say the hydraulic can leak and lose tension.
    – milesmeow
    Apr 15, 2019 at 16:30

The post should really be replaced, at the least add a new bottom utilizing a structural splice

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The issue with the structural splice, the new post section will not be the same dimension as the original, and will be quite noticeable. With a new post, it still may not be the same, but it will not be a noticeable as the splice.

Another way to do it is to either have a post custom cut to the size of the original.

Just a mention, it is wise to inspect the other posts at the very bottom. The post pictured since it is in the concrete a bit, the others will be too? The concern is the concrete or actually a course of brick pavers added after the posts were set, made a pocket to hold water which allowed the wood to rot most likely sooner rather than later.

  • Yes the other posts are in concrete too. They don’t seem to have any dry rot. What is the best way to check without damaging the posts. Just drill a hole?
    – milesmeow
    Apr 14, 2019 at 15:44
  • The screwdriver you were using would work on the worst spots by trying to insert it a the bottom were the post meets the concrete. An ice pick, scratch awl or another screwdriver that has a smaller blade will work too. If it sinks in easy, those posts would need repair as well. Drilling a hole would go in easy in any case, since it displaces the wood. It would give an idea still. The methods I mention above would need to separate the wood, which should be much more difficult to do.
    – Jack
    Apr 14, 2019 at 15:50
  • 1
    What about tapping for sound? If it sounds more hollow or less dense at the base that would be the first indication and then I would use an awl or ice pick.
    – milesmeow
    Apr 14, 2019 at 15:52
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    Before you install the replacement piece, place the bottom end in a bucket with about 2 inches of the best wood preservative you can find (alas, the good ones have been pulled from the market) and let it soak for several hours.
    – Hot Licks
    Apr 14, 2019 at 19:28
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    @Criggie, Drilling a drain hole may help, but not that much. Concrete acts like a sponge and will soak up any water it comes in contact with. It will still allow moisture to be in close contact with the post. The idea of setting the post on a pedestal is a good one, but not of concrete. There are metal pedestals that are made to fit under posts to elevate it above the concrete. This allows some air to get to the bottom to help the post bottom to dry out
    – Jack
    Apr 15, 2019 at 14:02

Take as much of the rotten bits out. Soak/spray 2 or 3 times the inside with an epoxy slow hardening paint, let it harden pref a few days, fill up the hole with a slow polyester selfmixing anchoring cartridge and similar wood

If you want to see the wood and not polyester, use the same wood 45°routed on the front. Epoxy spray the parts that will be in contact with the resin. Covering the wood with epoxy spray is because the polyester resin will be soaked up into the wood leaving the filler not to spec.

I use: http://www.ramset.com.au/Resources/Website/Product/Detail/img714p31.jpg

Make sure everything fits before mucking around with the poly

In the olden days i used old drained motor oil. 30 years on, the cheap pine still looks ugly and smelly but in good shape in the Netherlands

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