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ADrohen
Deck piers in high water table

Hey folks,

I have a deck that wraps around the front and side of the house and is at the 2nd floor level. The deck needs to be rebuilt this year, but more importantly the piers supporting the deck have been disintegrating over the past couple years and move quite a bit with the frost. A few of the piers have even moved from their original position and are at a lean.

There's a high water table to deal with also. At times the heaving during the winter is so bad that a couple deck posts will swing in the breeze, making a very unsafe situation.

I've started to investigate geotechnical engineers, but I thought I'd throw a thread out there to see if anyone else has had to deal with a similar situation.

The entire deck will come down this summer, but starting from the ground up, what should I do in order to build more stable supports in a high water table/frost heaving area of W. MA?

Thanks for any suggestions that may be of help!!
Andy

Wilddecks
Re: Deck piers in high water table

Are the post just sitting on top of the ground? Get a professional piling guy to wash some pilings down into the ground around 8'. Take some rebar and concrete down below the frost level to help stablelize it in the winters.

A piling guy is the guy who builds docks that has an auger.

ADrohen
Re: Deck piers in high water table

Thanks, I'll check on that.

The posts are on concrete piers. The piers are about 4 ft deep right now, which I would have thought was deep enough.

canuk
Re: Deck piers in high water table

If the piers are indeed 4 feet in the ground and still moving then ...... you either have to go further down to a more solid base or you might try something like the Big Foot system.

I really like this system .... it provides a wide footing which is better than simply the narrow profile of a pier ... also because of it's tapered design helps prevent it from heaving up.

http://www.bigfootsystems.com/

Just a thought.:)

chrisg00
Re: Deck piers in high water table

You can use a big foot system and dig all you want. I've used this system on a few jobs. From decks to additions, and even sinking homes, it's very economical, fast, and to building code. It's basically large (12-16")spirical bit, drilled into the earth. A small machine about the size of a large wheel barrell drills it down until it reaches necessary depths and readings. That may be 4' or 40'. The machine has a digital display the operator uses to know when to stop. Building dept. will get a whole breakdown of depths and soil readings from the installer after installed. I swear by this system. It's saved me a lot of time, money, and headaches!

http://www.tmpo.ca/about/publications/ottawacitizen.php?lang=en

http://www.yellowbot.com/techno-metal-post-of-mass-foundation-solutions-newton-center-ma.html

ADrohen
Re: Deck piers in high water table

Chris, this looks pretty good! I think it may be what I'm looking for. Any ideas on the cost at all?

Thanks for the help!

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