Every number here is a working estimate to check with your building authority. Whoever prints this page takes responsibility for what is in it.
Lessons / Footings, frost and posts
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4x4 or 6x6 post
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A 4x4 post under a 3 ply beam.
Every number here is a working estimate. Check it with your building authority.Turn JavaScript on to work the lesson. The drawing shows how it starts.
The rule this lesson teaches
A 4x4 needs a 2 ply beam, a post under 6 ft 6 in and a deck not more than 1.8 m (5 ft 10 13/16 in) up; otherwise a 6x6, up to 12 ft.