My uncle told me to always set posts in wet concrete, even in clay soil.

Tried it on a job in Spokane last week and now I'm dealing with three leaning sections after a heavy rain. Anyone have a better method for wet, heavy ground?

3 comments

3 Comments

wadeyoung1mo ago

Gotta disagree on the gravel collar, that just makes a bathtub for water in our clay. We dig deeper, set in concrete, but leave the top foot of the hole open and backfill that with pure clay packed super tight. Acts like a seal.

willow_anderson8525d ago

My buddy Joe tried that clay seal trick on his property near Puyallup, set six posts for a shed last spring. Two of them started leaning after the first big rain, the water just pooled around the top and softened everything up. He dug them out and found the clay seal had actually held water against the wood, rotting the bottoms in about three months. Switched to the gravel collar method after that, says the posts are still solid two years later. I think it depends on how wet your clay gets in the winter, some soils just don't compact right no matter how tight you pack em.

rowanp151mo ago

That Spokane clay is like setting posts in wet soap. My crew switched to using a gravel collar at the base for drainage, then backfilling with the native soil.