Choose ring shank nails or screws that are long enough to penetrate the joists by 11 2 in and space them every 6 in.
Strengthening roof joists.
How to strengthen beams using plywood.
Add an additional row of fas teners midway between the joists to pull the layers tightly together.
Long spans of joists in newer homes may wobble or bounce from foot traffic.
Joists and orient panel ends over joists.
Snow increases the overall weight of your roof adding to the forces acting on your rafters.
If the attic joists are not adequate one way to strengthen the floor for live loads is to sister the old joists.
When installing on the underside of the joists the process is the same.
You can however strengthen the joists.
Laminated and single piece beams are often reinforced with plywood.
Sistering is the process of adding a new joist next to each existing joist.
In the case of 2x6 joists you can pair them up with additional 2x6 joists by nailing them together side by side.
Strengthening existing roof rafters is a difficult process that often requires professional help.
As incremental parts of a building s structure joists are not easily replaced.