Concrete Control Joint Spacing

Where to cut contraction (control) joints in a slab: the spacing in feet (about 2-3 times the slab thickness, capped), the saw-cut depth (a quarter of the slab), and the panel grid with an aspect-ratio check.

Run the calculator

Formula and source

Spacing = min(factor x thickness, cap); depth = 0.25 x thickness; panels = ceil(length/spacing) x ceil(width/spacing); aspect kept under ~1.5:1.

ACI 302.1R / 360R slab-on-ground guidance (by name).

Audience

This tile is built for trades and the adjacent professions in the Carpentry and Construction group. The interactive calculator runs entirely in your browser. No account, no fee, no advertising, no tracking.

Related tiles

Posture

Rough Logic answers the math question the working professional asks on the job. The site is a calm, fast, ad-free, account-free, ever-free reference. It does not interpret code. It does not replace the licensed professional. It does not store your inputs. The Authority Having Jurisdiction governs all installations and inspections.