How To Level Old Floor Joists

A plywood subfloor will bridge any minor waves in the existing floor and leveling compound would help too.

How to level old floor joists.

A common scenario is to install temporary jack posts and support beams then permanent posts and beams over new footings. Set a hydraulic jack and post under the beam and jack up the joists about 1 8 in. If the uneven floor is due to floor joists that have warped or twisted over time or were incorrectly installed the only way to level the floor is to remove the subflooring and shim the joists. Leveling the floor with shims is when you attach thin wedge shaped pieces of wood on top of the low areas of the joists to make the top joists even.

Tack a beam under the sagging joists. Floors in older properties are very often out of level. If the floor slants irregularly cut strips that bridge the cap at each floor joist. If you have an uneven floor you may need to think about leveling floor joists with shims.

On the top side of the floor another fix it idea to lay down new hardwood over the existing floor. Nailing two 2x4s together will work to span about three joists unless the sag is under a weight bearing wall. Using a chalk line. A day until they re level.

Screw the strips into the floor joists or subfloor. Jacking them up too fast may cause cracks in the walls and floors overhead. The solution to sagging floors or the damaged sills and joist ends that contribute to them often involves jacking. You will have to make sure your joists can handle the addition of considerably more weight from the plywood subfloor and any floor coverings.

To do this simply cut several leveling strips the same size as the original strip. A taut string stretched across the floor will show the amount of deflection and improvement.