Your Deck Needs a Solid Foundation

Even though you may not see them, the posts (or footings) holding your deck form it's solid foundation and are vital for a strong, safe structure. A solid foundation means having the correct number of posts as well as ensuring they're properly located and solidly fixed in the ground and can't shift over the years.

Source: http://www.doityourself.com/stry/your-deck-needs-solid-foundation

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