Sistered Sistering Floor Joists
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Doing so strengthens weak joists and can help straighten sagging joists.
Sistered sistering floor joists. How to sister a floor joist. Sistering joists means beefing them up with additional material. This article provides step by step instructions and pictures on how to make structural repairs by sistering floor joists alongside weak joists. If you have sagging cracked or twisted joists which can happen in older houses this project will provide the extra support the floor needs.
So a 2 foot extension will be 4 feet sistered to the existing joist with appropriate fasteners 3 nails in a w pattern every 12. Properly sistering floor joists is very important and should not be rushed to save time. Since this is a repair of a faulty or damaged floor joist it is imperative to do this project correctly and there are a few big mistakes to avoid.