Leveling screw jacks are residential construction tools that home improvement specialists use to level sagging, uneven floors. Leveling screw jacks are typically placed under the floor, supporting it while adjusting for changes in load.
Screw jacks come in a variety of heights and offer various screw adjustment lengths. Additionally, home improvement specialists can purchase leveling screw jacks with thrust bearings installed inside the adjustment nut. These bearings reduce friction when the screw jack adjusts to changes in load and offers the ability to jack weight effectively.
Heavy floors typically require the use of hydraulic leveling screw jacks. By adding in a hydraulic element, it is possible for a leveling screw jack to lift over 4,000 pounds of weight.
To install leveling screw jacks, climb into the structure's crawl space to gain access to the underside of the floor. Place the screw jacks on concrete piers, and place lumber into the screw jacks. Once the lumber is in place, secure the lumber to the frame of the floor at a perpendicular angle, and jack it into position. A splicer may be necessary to ensure a good fit. If the floor is warped or otherwise not level, install screw jacks at every two-foot junction for the best results.