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User1234
Deck raised again due to frost heave!

2 summers ago we put in a new deck. Unwise at the time, we didn't know that we required a permit to replace a deck so no permit was used. We did use a sonotube but we put the post in the tube along with the concrete at the advice of a local lumber yard. We found out after that we should have placed the metal connector on the top of the concrete at the top. I don't know if this has anything to do with the problem we are now having as the issue that I became aware of was that it could cause the wood to prematurely rot. We did put the concrete down to 5' instead of the recommended 4' (Ottawa) since we thought this would protect even more against frost heave.

Last year, our deck raised around 3" and we accepted that it could just settle that way. This year around 3" more! We have a definite slope towards the house now. I'm not sure what to do to fix this. Should we rip out these posts and replace them? We have a high water table, so could that be the problem - should we not have gone to 5'? Should we undo the bolt at the top and cut the post shorter? Is there anything that we can do that would prevent this from happening again???

All assistance is greatly appreciated!

jkirk
Re: Deck raised again due to frost heave!

well you only need to put the sonatube down 4 ft in ottawa, its the standard code right across canada. however if the tube is sitting on disturbed soil the post can sink as rain and such causes the dirt to settle more and more.

if the deck is heaving up towards the outside it will settle back down.

best bet is to post some pictures though so we can get a better idea of whats going on

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