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A sister stud is a secondary stud that is installed alongside an existing stud.
Sistering can also be done to reinforce undamagedfloor joistsor rafters.
Non-load-bearing walls are usually interior partition walls that don’t carry structure weight from above.
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It serves as a jot down of splint that reinforces the bad spot in the stud.
With non-load bearing studs, the sister stud doesn’t need to be a full-length stud.
Load-Bearing
Sistering with a partial stud is not allowed by most building codes for load-bearing walls.
The sister stud must be anchored to both plates as well as to the damaged stud.
It picks up on some of the remaining structural support left by the damaged stud.
It also allows you to avoid the somewhat messy job of pulling out old studs.
Aim for about 1 to 2 feet of extension both above and below the damaged area.
Sister One Side Only
You only need to sister one side of the stud.
It’s not necessary to sister both sides.
When you hammer, the stud will vibrate or collapse.
The replacement fire block must be cut to fit and reinstalled after the sister is in place.
Instead of cutting the previous block, use a new two-by-four to cut the replacement fire block.
Replacing Insulation
Exterior wall studs that have been sistered have insulating surrounding them.
If theinsulationis in good shape, it can be reused.
To accommodate the sister stud, cut away 1-1/2 inches from the side of the insulation.
Leave the paper facing material intact.
Make certain that this sistering job has not been made necessary by some larger problem.
