How to Pour a Concrete Slab

The full process of pouring a concrete slab, from building the form to curing the finished surface.

Build the Form

Set the perimeter
Stake and brace 2x4 or 2x6 forms to your finished slab dimensions.
Level and square
Check the top edges are level and the corners are square.
Set the gravel and vapor barrier
Account for base and barrier choices before pour day.

Reinforce

A grid of rebar or welded wire mesh keeps the slab from cracking. Lay it raised off the ground and tied at the intersections so it sits centered in the slab thickness.

Estimate and Order the Concrete

Cubic yards = (length × width × thickness) ÷ 27

Add wastage then order bags or ready-mix. Have help and tools staged before the truck or mixer arrives — concrete sets on your schedule, not the calendar's.

Pour and Finish

Screed
Pull the surface flat along the forms.
Float
Work out to a smooth, level surface as bleed water comes up.
Trowel and edge
Finish with a steel trowel and round the edges.
Cut control joints
Score joints early to control future cracking.

Cure

Keep fresh concrete damp for several days — cover it with plastic or wet it down. Curing concrete that dries too fast is weaker and more likely to crack.

Related Calculators

Disclaimer: Figures on this page are general reference information. Always verify exact requirements with your project specifications and a qualified professional.