Decks, Patios, Porches and Docks - whats happening to my deck?

Hi,
We bought a house last spring, and this past winter (New Hampshire) we found that the middle of the deck rose probably 4 inches. Now it might have been that way and we hadn't noticed. But anyway, my husband thought that if he cut the middle post down at the bottom (sorry if I'm not technical!), that the deck would relax and come down...but all it did was have that middle post hang there.
Now, almost 8 months later, it hasn't relaxed. Any idea what to do?

I've attached a photo, not sure if it will come out..
thank you!

sophie,

What might have happened is not properly installed post footings when the deck was built. Depending on the age of the deck, the freeze (uplifting) and thaw (relax mode) have caused some permanent conditions which will not just go away on their own.

It appears that you need to replace the post footings to the right depth as they are not that way right now. More than likely the post footing bottoms are at or above the frost line within your area. This continual movement will always be a problem and it will, or shall I say has ruined your deck.

If you are able to salvage the wood, great but I fear that you will have to replace what you see as "damaged" or "unrepairable" with new once proper size footings are in place.

Hope this helps!

Thanks for the quick answer. I believe the deck is only 3 years old. Besides the "lump" in the middle (and the now hanging middle post) everything looks ok.
Do we really have to replace it, what will happen if we just leave it?
here is the pix

http://www.usahostels.org/cape/secret5.htm

Sophie,

What I see is the center post under the beam has been cut. This is not considered wise and by rights it should be replaced. You are fortunate that this is at a location that digging it deeper is attainable without too much problem. My concern is if this one is doing it, are the others? It may be all you need to do but a deck 3 years old may have been too long as the other material associated with this problem, like "bowing" or "warping" may have ruined some deck boards as well.

I would suggest total replacment of the post once the new footing is in place. Here are some links to what should be done to make it simpler.

http://www.sustland.umn.edu/implement/deck_footings.html

http://www.handymanusa.com/articles/deckbuilding2.html

I hope this helps!

I have been following this post......my deck is doing the same thing... how does one find the frost depth for any area?..... I always thought 4 ft would be sufficient, but perhaps the footings need to be even deeper in NH:eek:

tobyo,

Contact your local building official! 4 foot is usually the minimum.

Let us know what your's is, ok?