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Community and Q&A

Cinder-Block Foundation for Small Log Cabin

arnoldk | Posted in General Questions on


I am getting ready to prepare the pillars for a small 9′ x 12′ log cabin I will be building from the trees I need to cut for where the main house will eventually go. In order to avoid having to pull a building permit, the total square footage needs to be under 108.

I am thinking about using cinder block stack two high to keep things simple and quicker to complete to work. Once completed I will be wrapping the pillars with wood to hide the cinder block.
The site where I will be building the log cabin has bedrock a few inches belong he soil which I will remove. The location is flat with only a few inches in height difference from corner to corner.

I have a few questions:
– How do I determine how many pillars I will need to support the cabin?
– Do I need rebar and if so how many per pillar?

Thank you for your help,

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  1. walta100 | | #1

    Note in most places the 108 square feet is not measured inside corners of the interior as most would assume, but rather from the exterior corners of the building. Your longest wall must be less than 10.4 feet if you are pushing the limit get a written ruling (Email would be bests) in advance if they are measuring interior or exterior space if exterior will protruding tails of the logs be counted.

    Generally when they put such a small limit on shed/ out building size they also forbid and concrete foundation so no rebar allowed. Again get it in writing before you start.

    The number of pillars depends on you floor design. A dirt floor harden with blood was common. But that put the lowest log in contact with the ground so that log would rot away in a few years.

    If any wood will be in contact with the ground try to make that log be Osage orange / Hedge apple as it will last the longest. Black locust is also very good.

    Note all door and window opening must be built to allow for the wet log to shrink as they dry over the next 10 years. The logs will get about 7% smaller across the round direction but the length will not change.


  2. arnoldk | | #2

    I've decided to keep things simple and just building the cabin on one 10 inch cinder block every 3-4 feet. No rebar or concrete will be needed in this scenario.


  3. Expert Member


    Just a caution about permits. If you are supplying power to the building it will need an electrical permit. And if you are intending to use the building to sleep in it will need a building permit. The size exemption only applies to accessory structures not used for living in (storage sheds, etc.).

    1. arnoldk | | #4

      Hi Malcolm,

      The cabin is not going to have any amenity (water, electricity...) and it is simply a place to store equipments and get out of the weather while at the property.

      Thank you,

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