Step 1: Planning, Layout & Square Staking

Measure your slab footprint and drive wooden stakes at each corner. Use the 3-4-5 Pythagorean triangle method (or measure diagonal corner-to-corner distances) to verify that all form angles are exactly 90 degrees.

Step 2: Excavation and Subgrade Preparation

Dig out all organic sod, topsoil, and loose material to a total depth equal to the slab thickness plus the gravel base (e.g., 8 inches deep for a 4-inch slab on 4 inches of crushed stone). Run a mechanical plate compactor over the bare earth subgrade.

Step 3: Installing & Compacting the Gravel Base

Distribute 4 to 6 inches of #57 crushed stone or dense-graded aggregate. Compact thoroughly in 2-inch lifts. A solid, uniform base prevents cracking and provides critical drainage.

Step 4: Building & Bracing Formwork

Erect straight 2x4 (for 4" slabs) or 2x6 (for 5"-6" slabs) lumber forms. Secure them with wood or metal stakes spaced every 3 feet. Slope the forms slightly (1/8 inch to 1/4 inch per linear foot) away from any adjacent house foundation to ensure positive rainwater drainage.

Step 5: Placing Vapor Barrier & Rebar Reinforcement

Lay down a continuous 10-mil to 15-mil polyethylene vapor retarder sheet. Overlap seams by 6 inches and tape with vapor tape. Place #4 (1/2") steel rebar on a 12-inch to 18-inch grid pattern, supporting the rebar on concrete or plastic chairs so it remains centered within the slab depth.

Step 6: Pouring, Screeding, Floating & Curing

Discharge the ready-mix concrete starting from the furthest corner. Screed the wet concrete flat using a straight 2x4 straightedge resting on the form tops. Bull-float the surface immediately to push large aggregate down and bring cement paste to the top. When surface bleed water disappears, apply a non-slip broom texture and cut control joints at intervals equal to 2 to 3 times the slab thickness in feet (e.g., every 8 to 10 feet for a 4-inch slab).