Shows raisinge a sagging floor gradually with bottle jacks.
How to jack up a floor.
Slowly jack up the floor.
Use a hammer a nail puller and a sledgehammer to remove the existing underpinning wood post and nails.
After they were in place we hoisted up the 4 x6 x8 beam so that it crossed all four of the new joists sliding the screw jacks underneath.
Use a hydraulic jack and a short post to shore up the floor during this process.
Use a string to watch the floor come up.
You will have to make sure your joists can handle the addition of considerably more weight from the plywood subfloor and any floor coverings.
Carefully hoist the jack until the beam reaches the floor underneath.
The 4 inch lally posts can be replaced by 6 x 6 inch lumber.
On the top side of the floor another fix it idea to lay down new hardwood over the existing floor.
Place a jack on the inside edge of each outside footing.
A common scenario is to install temporary jack posts and support beams then permanent posts and beams over new footings.
Make sure that the lumber or lally posts are perpendicular when jacking or they may slip out of position.
Underneath the floor in a crawl space or basement position the floor jack or jacks and place the beam in position.
Raise each jack by 1 8 inch at a time this will help to reduce any damage to window frames and plaster or drywall walls above the floor.
A taut string stretched across the floor will show the amount of deflection and improvement.
Block under each one until there is just enough room to fit the girder between the jacks and the joists.
Continue to raise the jack until you feel some resistance.
The solution to sagging floors or the damaged sills and joist ends that contribute to them often involves jacking.
A plywood subfloor will bridge any minor waves in the existing floor and leveling compound would help too.
Center the screw jack below the girder and on top of the wood block on the concrete pier.
Place support of the floor joists with wood studs.