Timber decay and woodworm
The foot of a porch post is soft with wet rot, and the hall floor is also timber. Why does the porch post not prove the hall joists are decaying?
Not a porch post with wet rot at the foot proves the hall joists are decaying. The post foot is an exposed end in the weather, soft where rain reaches it. The hall floor is different timber in a different place, and this note does not probe it. Wet rot in the porch stays local to that post until something in the hall is actually found to be soft. A visual survey records the post. It does not carry the diagnosis indoors, and it does not design a new hall floor from a porch foot.
Last reviewed 24 October 2026. Written for buyers in England and Wales unless this answer says otherwise. No named surveyor has signed this page. It is general guidance, not a report on your house, and not legal advice.
What is the fuller explanation?
Porch posts fail at the bottom because the end grain sits in splash, often in a socket that stays wet. That is not the life of a hall joist spanning an internal room, even if both are timber and both were looked at the same morning. A real link would be a wet threshold or a joist that is itself soft. This sentence does not say that. It says the foot of the porch post is soft with wet rot.
Repair the post as a post. A joiner can splice or replace the decayed foot so the porch roof still has a support. Ask them to stop at the porch unless they find decay in the hall and write it down. Do not let the estimate swallow the floor joists because the post is also timber. The survey did not find that. If the hall worries you, have those joists seen as their own item.
What should you ask your surveyor?
- How far up the porch post does the softness go, and is the hall threshold wet?
- Did you test any hall joist, or only the foot of the porch post?
- Are you linking the porch structure to the hall, or keeping them apart?
What are the typical next steps?
- Price the rotten foot of the porch post as its own repair.
- Do not include the hall joists unless a separate defect is written down there.
- Ask the joiner to stop at the porch if the hall timbers are still firm.
Costs vary with the building and with who you instruct. Where this page does not cite a published figure, ask the surveyor, a relevant specialist, or your solicitor for a written quote. Do not treat a forum average as the price.
Also asked about this
Does wet rot in the porch post show the hall joists are going the same way?
No. The soft foot is outside, in the weather. The hall joists were not shown to be decaying, and the porch post does not prove they are.
Can the porch post be ignored because it is not part of the house floor?
No. The foot is soft and needs a joiner. That repair is real, and it still says nothing about decay in the hall joists.