How to Sister 2x10's

Old 10-13-22, 09:06 PM
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How to Sister 2x10's

I have a deck which is 36 feet long. It has piers every 6 feet, therefore the joist span is 6 feet. How do I sister the 2x10 together. I am going to use 12-foot length boards. What do you suggest: Nails, Lag screws, or bolts. What size how far apart? How far from the top and bottom edges and ends? If you suggest lag bolts what size pilot holes?
Old 10-14-22, 05:34 AM
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Assuming you have 7 piers.Your support beam will consist of three 12 ft boards on one side and two 12 ft and two 6 ft (one each end) on the other side. All butt joints fall on a pier. Use pressure treated boards and galvanized attaching hardware. I am not qualified to suggest size and location of attaching hardware.
Old 10-14-22, 11:21 AM
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Your codes will specify what fastening they want when building a beam. You didn't say where you are located but some areas have stricter or different requirements. You can look at the International Building Codes (IBC) for a start. Also, since decks are often a DIY project and are often done wrong... many building inspection departments have a flyer prepared to guide you through the most common problem areas like; footings, how to attach to the house, stairs, railings, beam requirements...

The code might say that you need a minimum of four 3" long nails evenly spaced in a line across the beam from both sides. Each row of nails every 16".

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