How to correctly build the foundation of a two-post car lift?

Building a proper foundation for a two-post car lift is critical for safety, stability, and performance. Below is a step-by-step guide outlining the correct way to construct the foundation:
1. Follow Manufacturer Requirements
Every lift manufacturer provides specific foundation requirements, which typically include:
Concrete thickness
Concrete strength (PSI)
Anchor bolt specifications
Always check and follow these before proceeding.
2. General Foundation Requirements
Concrete Thickness
Minimum:4 inches (100 mm)
Recommended:6–8 inches (150–200 mm) for heavier or commercial-duty lifts
Concrete Strength
Minimum:3,000 psi (21 MPa)
Preferred:3,500–4,000 psi (25–28 MPa)
Reinforcement
Rebar grid or mesh is recommended to prevent cracking and improve load distribution.
Spacing: Rebar #4 or #5, spaced at 12–18 inches on center.
3. Slab Dimensions
Width: At least 10 feet (3 meters) between columns
Length: Around 18–20 feet (5.5–6 meters) overall for vehicle clearance
Flatness: Surface must be level within 1/8 inch over 10 feet.
4. Location & Soil Check
Ensure the lift is installed indoors or under cover.
Avoid areas with soft soil or backfilled trenches.
Compact soil well and consider footings if soil is questionable.
5. Curing Time
Allow at least 28 days for concrete to cure before installing the lift.
Avoid drilling into fresh concrete.
6. Anchor Bolt Installation
Use specified expansion bolts or chemical anchors.
Drill holes using a hammer drill after layout is complete.
Clean the holes thoroughly before anchor insertion.
7. Layout & Drilling
Use a chalk line or laser to mark the exact column positions.
Double-check center-to-center distance and squareness of layout.
Important Tips
Never install a lift on asphalt, brick, or old cracked concrete.
Do not use epoxy patches to make up for weak concrete.
If unsure, consider hiring a structural engineer to verify slab integrity.