Retaining wall cap calculator

Use the cap’s installed coverage

The cap count is the wall run divided by cap coverage, rounded to a whole cap, with the entered allowance added. The coverage can differ from the face block length. For a taper, curve, return or corner, measure the part of the cap that follows the selected wall alignment.

An end-to-end cap run with 16-inch coverage needs 23 net caps for 30 feet. With 10% cutting allowance, the order is 26 caps. That estimate does not include a separate decorative overhang, special corner cap or unusual joint.

Caps = ceil(ceil(wall run ÷ cap coverage) × (1 + waste/100))

Adhesive coverage depends on the bead

Enter the number of continuous beads and the total bead length one tube covers at your chosen diameter. The tool multiplies wall run by bead count and the allowance, then divides by tube coverage and rounds up.

A 30-foot run with two beads and an illustrative 30-foot-per-tube coverage takes 60 feet of net bead. Ten percent allowance increases it to 66 feet, so the result is three tubes. This is an example calculation, not a coverage claim for a particular adhesive brand. Check the product label, temperature requirements and approved bonding surfaces.

Curved caps need a layout check

A curve can produce joint gaps even when the total run is known. Tapered units, manufacturer radius limits and saw cuts determine the finished fit. Use the curved wall tool for arc length, then verify the cap layout with the supplier.

Keep cap costs separate from structural units. Caps often come in a different package size and may have a different return policy. Ask whether a factory end cap or corner cap is needed before placing the order.