Supporting failing deck with cinder blocks?

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I have a house with a large back deck. There is a sunken portion that is substantially reinforced to hold a hot tub, which we've used to support an inflatable-ring-type pool. After quite a bit of rain, the ground softened and we found that one end of our deck had sunk, the supporting 2x12'' beams resting on the ground. Upon inspection, the 4x4'' posts were termite-eaten and had rotted to be only 2-3 feet long. No concrete footings to be found. We jacked up the deck and installed cinder blocks sandwiched between 2x6'' boards to support the weight and it's back where it should be, but what should I do at this point? Of course renting a post hole digger and installing proper footings and new 4x4 posts is ideal, but we're on a budget. Are cinderblocks sufficient as a temporary fix?



Comments

  1. DrDontheTermiteGuy says:
    January 17, 2011 at 10:57 am

    First kill off the termites or they’ll be in the house as well.
    Cinder blocks don’t really tie it to the ground, so that it may move sideways under load. Not nice. The blocks may be enough for you local building code, but you’d better check the rules. Whatever you do, make it so that the wood posts aren’t in the ground. Use metal stirrups instead. Hunt around, some brands just screw into the ground–very easy.

  2. The Soundbroker says:
    January 17, 2011 at 10:57 am

    The problem with temporary fixes is that they become permanent. If there are no concrete footers then you need to get a proper foundation in under those supports and replace the deck supports with new pressure treated lumber (make sure you use pressure treated fasteners and connectors!). If you want to use the deck, don’t eat out for a month, skip the movies, save up the $100 or so it might take. All your really need is a shovel, a cheap section of sonotube concrete form, a few bags of high strength cement, some post anchors and some sweat to make a proper foundation. A weekend of labor will make it far safer for over a decade. If that deck collapses with people on it and investigators find the temp fix, you are liable and the lawsuit or medical costs will be FAR greater than the costs of repair. Until then, I would close the deck.

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