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I’ve got a 60s era carport with a rotted post. It’s a low slope cantilevered roof about 20 feet long. It has two posts on each corner at the front, and the back is supported by the house.

The rotted post is a 2x4 sandwiched by 2x6s like an I beam.

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enter image description here I could replace it as built, Doug fir 2x. The roof is big enough that I’m a little concerned about a 2x4 holding up all that load.

The pier this rests on is perfectly sized for a 4x6. What holds me back from putting in a 4x6 is I don’t know about cutting a birds mouth into an existing beam, and the pier is not very level.

What do you all think? As built or how to sub in a bigger column?

Daniel Griscom
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monknomo
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1 Answers1

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The post looks reasonably adequate as it was originally built even by modern standards. If it wasn't you'd have seen disaster long ago, when it first started to decay.

To maintain the style detail I'd rebuild to match, using pressure-treated lumber. By doing so you eliminate the need to cut that notch and you end up with a more robust post. A single post member may have weaknesses that are addressed by using multiple boards. To be clear, each board should be cut accurately to fit its bearing points on each end. It's not just the center board carrying the roof load.

I'd fit everything and screw it all together at 18" intervals with pairs of 3" corrosion-resistant deck screws from each side. After it dries out for a few weeks, use a high-quality wood filler to flatten out the screw heads, then prime and paint.

isherwood
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