Q&A: Nailing Joist Hangers

A.David Utterback responds: The short answer is yes, you want to have a nail in every hole. It’s the shear and the withdrawl resistance of the nails that carry the structural load, and joist hangers are sized with a specific number of holes to carry specific load ranges. Typically, wider dimension members carry heavier loads, so deeper joist hangers have more holes in them for more nails.

Just as important is using the right type of nail. I can’t count the number of houses I’ve been to that have box nails, 8d galvanized nails, even roofing nails, instead of the common nails recommended by the manufacturer and required by code.

All hanger manufacturers have specific nail recommendations. Typically, the least you can use for a single joist hanger is a 10d common. The short joist hanger nails are also 10d nails, and they can be used for single joist hangers.

When it comes to double joist hangers and beam hangers, however, you need a full-length 16d common nail. When you’re hanging a beam, you won’t be hanging off a single member, so you don’t have to worry about a full-length nail sticking out one side.

Don’t use box nails or roofing nails, and don’t substitute 16d sinkers for 16d commons. You can use 16d sinkers only in place of 10d commons.

David Utterback, of the Western Wood Products Association, provides technical information and gives building code seminars throughout the country.