How To Jack Up Floor Joists

The sagging floor was the symptom and somewhere under the house there had to be a cause.

How to jack up floor joists.

Well after doing the navy seal crawl up under the house we found that the joists that were supporting that floor were not actually attached to the sill plate any longer as seen in the photograph below. It is critical to use heavy steel plates between the jack and the beams to avoid crushing wood fibers in the beams destroying their integrity or worse yet punching a hole through the floor. Stretch a string across the floor to evaluate the amount of deflection then use it as a benchmark for improvement when jacking. The only tools required is a bottle jack string straight claw hammer circular saw and a light source.

A day until they re level. Where these repairs are not sufficient also consider shoring up joists or beams that were cut drilled or notched for pipes wires or ducts. Drive 16 penny nails through the holes in the plates and into the wood framing. Make repairs to settling piers and weak joists to fix swagging floors and roof lines.

On both sides of the problem area. Jacking up a floor and leveling it is easy with these simple instructions. Lower the hydraulic jack to transfer the floor load to the new screw jack. Adjust the screw jack up or down to achieve a level surface.

If a crack or sag is isolated to one area the sister joist should extend at least 3 ft. Tiger brand adjustable floor jack model js 15 15 gauge floor jacks telescoping jack for temporary support size range 1 1 3 4 4 out of 5 stars 368 19 67 19. Adjust the screw jack so that the top and bottom plates are flush to the wood surfaces above and below. The steel plates should be a minimum of 25 inch 0 6 cm thickness and large enough to distribute the full load of that jack across the beam.

Jacking them up too fast may cause cracks in the walls and floors overhead.