Preface - this house is located in China, where permits and contractor certifications are not a thing, and there is basically no legal remedy for compensation over shoddy work.

Last year we had this deck put in by a local team. The large posts (4) are 155~165mm square, and 3160 to 3310mm tall (the driveway has a minor slope). The smaller posts (2) are 80~85mm square.

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This year large cracks have developed in most of the posts. The cracks are mostly 15 to 20mm in depth, but some run as deep as 50mm. They occur on multiple sides of the posts and tend to run more than half of the height of each post.

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We are unable to locate the original contractor. We brought in another local last week and he said:

  1. they're fine, don't worry about it
  2. I could stick some glue in the cracks if it would make you feel better
  3. I guess I could put bolts through the posts if you're still not happy

I know nothing about carpentry, but I do understand frost-wedging. Our climate here features 3 to 4 months each winter continuously below 0 Celsius, so when I see those cracks I get very nervous with winter on the way.

Assuming these cracks ARE a problem, my initial reaction was that short of replacing them outright, some sort of steel banding would be a reasonable solution. I'm not keen on adding MORE holes unless the bolts are affixed to large external pressure plates but he wasn't going to do that.

Is this a problem? If not, will it become one soon?

Full album with additional photos: https://imgur.com/a/JEfrx

  • 1
    As Michael Karas described, it is common for posts to develop cracks like that. What is important is where the cracks are and how they run. The pictures show the cracks running along the middle of the posts. If they were to split all the way through, you would still have two solid uprights, so the cracks aren't seriously affecting their strength. Diagonal cracks are more worrisome; you can end up with two wedges and the load wants to push them apart. If you would feel better reinforcing them, a series of bolts will do it. Glue is a waste.
    – fixer1234
    Sep 24, 2017 at 23:21

1 Answer 1


It is rather common for posts of that sort to develop cracks like that if they were cut from logs and then installed without being kiln dried. Even kiln dried timbers can develop cracks along the long grain but that will happen to a lesser extent.

Cracks like that appear when timbers dry out in an uneven manner. They should not greatly affect the vertical support strength of the posts. You can watch them and if one post also begins to warp or twist then you would want to get it replaced.

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