I’m in the process of planning a wraparound deck in Maine that’s 8 feet high on the backside of the house. Been getting mixed advice regarding the posts – some say sinking treated posts attached to footings to about 4 feet is adequate, or even better than using concrete piers/footings, which may be more suseptable to frost-lifting. Anyone up north willing to share your experiences/thoughts on this? Thanks.
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Hi, I'm out in the middle of Penobscot Bay.
Either way can be fine.
If you use sunk posts, set them on a pad or drop a bag of Sakrete premixed into the hole to let harden in place and it will be the support. Then wrap the post with plastic or foam.
If you use concrete piers, be sure they are set below frost depth (four feet here) on firm footing. I like tamped stone base of 3/4"washed or inch minus. But also be sure that the concrete doesn't stick above grade level by more than a couple inches because it can act as a thermal conductor, wicking the ground heat out of the ground to radiate it into the air. This can let the ground freeze deeper right at the pier than it does in surronding soils.
The reason for plastic or foam wrap on the wood pole/post sunk is that even if the soil only freezes 18" or 24" deep, if it is frozen to the post, it can lift the post as the freezing soil expands. With a detached slippery surface, the soil can slide past it.
Excellence is its own reward!
Thanks for that helpful advice - I'm also wondering if using the post-only method might lessen the perceived value of the deck to the average would-be buyer because they expect to see concrete. Do you think that's a realistic concern?
Not to me. I'd rather see PT into the ground than some of the post to concrete copnnections I've seen, especially when they are failing. You might want to run this by your loval building inspector too, if you have one. .
Excellence is its own reward!
Well, that represents a consensus between you and a couple of other guys who's opinions I respect. I'm convinced - Thanks again.
That's me, consensical to the n-th degree.
;).
Excellence is its own reward!
I would drive down to the city buiding dept. and ask them for a building code list for decks in that city,because believe me they vary from one city to the next.This doesn't bring attention to or red flag your project, it just provides you with the nessesary information for that area.
The reason for getting a permit for decks above 30" off the ground is to protect the homeowner, too many questionable means of construction have been used over the years on "easy" jobs like decks, and have caused injuries to people that have used them. Bob
"Rather be a hammer than a nail"
Thanks for that advice; my town's code enforcement officer has looked over our plans (which made accomodations for either the post or post and pier method) and apparently they met local requirements.