How do you safely replace a rotted porch post?
Rotted or damaged structural porch posts need to be replaced while properly supporting the weight overhead using a temporary jack post. Failing to secure the structure before removing the old post risks a collapse, while hidden rot caused by failed flashing often damages underlying boards and pillars.
What people tried
Every workaround mentioned in the threads below. We haven’t tested any of them — and nobody here is claiming they worked.
- 1Installing a temporary jack post right next to the original to support the structure
- 2Placing a block down on the ground to support weight before removing the old post
- 3Replacing the old post with a steel post and building a non-structural box around it
- 4Supporting the 6x6 beam with jack posts, cutting out the rotted portion, sistering in a replacement piece with metal plates, and installing a post bracket on a concrete slab.
In their words
Unedited, grouped by where they were said, most upvoted first within each place, each linked to the thread it came from.
“We recently received a code violation for our porch boards and steps needed to be replaced but I think this post needs to be replaced too how would you do this?”source ↗
“A temporary post right next to it quickly take out the old one replace to boards under it and then add a new”source ↗
“Anyway, the paint was getting a little long in the tooth, so I went up there to prep and paint and one of the boards that make up the box was totally rotted out and just came off with zero effort.”source ↗
“The 2x4 is basically done and the 6x6 is rotted in the area above the pillar but sounds pretty solid further away from it.”source ↗
“The source of the rot appears to be that some metal flashing between the 6x6 and the 2x4 failed and then water just started getting in there (PNW so there's plenty of that).”source ↗
Where this came up
People with this problem also raised
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