4x4 Screw Jack Post 14.5in-18.5in Adjustable House Jacks - Heavy Duty

In this review of the 4x4 screw jack post set, the bottom line is straightforward: builders and DIYers who need temporary, adjustable support for joists, beams, and short-term shoring will appreciate the solid capacity and simple operation. The package reviewed includes two screw shore jacks and a metal handle, and the single biggest reason to buy is the high working load capacity paired with a compact footprint that fits 4x4 lumber. This is a practical tool for leveling floors, supporting beams during repairs, and stabilizing short posts in crawlspaces or basements.

Key Features

• Package contents: Two screw shore jacks and an 11.8in metal handle provide everything needed to start shoring without buying extra tools.
• Height adjustment: The jack adjusts from 14.5in to 18.5in so it can cover a useful mid-range of lifts for flooring and foundation repair tasks.
• Base mounting options: A 3.5in x 6in base plate with four 0.5in and two 0.3in mounting holes offers flexible installation to secure the jack to a floor or footing.
• 4x4 compatibility: The jack is shaped to accept standard 4x4 posts directly, making installation quick when using common lumber sizes.
• Durable construction: Made from alloy steel with a protective black coat, the jacks resist corrosion and stand up to repeated use on job sites.
• High load capacity: Rated for up to 24,700 lbs, the jacks provide substantial temporary support for structural lifting and repairs.

Who It's For

This product is aimed at contractors, tradespeople, and experienced DIY homeowners who need a reliable temporary support solution for leveling floors, supporting beams during replacement, or stabilizing short posts in basements and crawlspaces. The high load rating and compact base make it suited to renovation work where controlled adjustment and strong support are required.

Those who should look elsewhere include users who need very long travel jacks, continuous permanent support systems, or jacks specifically sized for posts other than 4x4 without shimming. Also, anyone unfamiliar with safe shoring practices should consult a professional rather than rely solely on temporary screw jacks.

Pros & Cons

Pros

• High working load capacity gives confidence when lifting or supporting heavy timbers.
• Simple turn-handle adjustment with the included metal wrench speeds setup and changes in height.
• Compact design fits neatly under 4x4 lumber and the base plate offers versatile mounting options.
• Durable alloy steel construction with protective coating resists wear and corrosion.

Cons

• Intended for standard 4x4 posts; 3.5in x 3.5in posts will require shims for a stable fit.

Specifications

Package	2 screw shore jacks + 11.8in metal handle
Height range	14.5in - 18.5in
Base plate size	3.5in x 6in
Mounting holes	Four 0.5in and two 0.3in holes
Compatible post	Designed for 4x4 lumber
Material / finish	Alloy steel with black protective coat
Working load capacity	Up to 24,700 lbs

Our Verdict

The 4x4 screw jack post set is a practical, heavy duty choice for anyone who needs temporary adjustable support for floor leveling, beam repair, or short-term shoring. With a high working load, straightforward height tuning using the included handle, and a compact base plate, it represents solid value for renovation work when used with proper shimming for nonstandard posts.

Frequently Asked Questions

Can these jacks be mounted to a floor?
Yes, the base plate includes multiple mounting holes so the jacks can be fastened to a suitable floor or footing for added stability.

Will a 3.5in x 3.5in post fit?
A 3.5in x 3.5in post is smaller than a 4x4 and will need shims around all sides to ensure a stable seat in the jack.

Are these suitable for permanent support?
These jacks are intended for temporary shoring and adjustment during repair or construction, not as a permanent support solution.