Cap Stone Buying Guide for Arkansas Walls: Overhang, Thickness, and Ordering by the Foot
Cap stone is the last course a wall gets and the first thing everyone sees. It is also the part of the wall doing a job nobody thinks about: shedding water. An uncapped stone or block wall drinks rain straight down into its core, and in Arkansas, where a wet fall runs into freezing January nights, that trapped water is what cracks mortar joints and pops faces off block. The cap is the roof of the wall. Get it right and the wall underneath lasts decades longer.
This guide covers what cap stone does, the sizing rules that make caps look intentional instead of tacked on, and how to order them. Rockhouse Stone is the supplier in this story. We stock, sort, sell, and deliver the caps; your mason sets them. But since caps get ordered wrong more often than almost any stone product, the numbers below are worth five minutes before anyone places an order.
What a cap actually does
- Sheds water. A solid cap with a slight wash keeps rain out of the wall core. This is the difference between a wall that weathers and a wall that deteriorates.
- Finishes the line. The cap gives the eye a continuous top edge. Even a rough fieldstone wall reads as finished once a consistent cap runs across it.
- Makes the wall usable. A flat 12 to 14 inch cap turns a seat-height wall into actual seating. Patio walls around here get sat on constantly; the cap is what makes that comfortable.
The three cap types you will order
Wall caps
Flat stock, usually 2 to 3 inches thick, cut or snapped to the wall's width plus overhang. These run by the linear foot along the top of retaining walls, planter walls, and skirting. If your wall curves, say so up front; shorter pieces follow a radius far better than long ones.
Column caps
Single square pieces that top columns, gate posts, and mailbox surrounds. The rule here is one piece, not four. A column cap made of one stone sheds water outward in every direction with no seam to leak. Common sizes top columns in the 16 to 24 inch range, and each cap should be sized to the finished column plus overhang, not to the block core underneath it.
Step and seat caps
The same flat product doing double duty as a step tread or bench top. If any part of your wall doubles as a step, order those pieces with the tread rules in mind; our guide to natural stone stair treads covers the thickness and depth numbers.
Sizing rules that make caps look right
Overhang: 1 to 2 inches per side
A cap flush with the wall face looks unfinished and dribbles water straight down the stone. A cap with 1 to 2 inches of overhang on each face throws a clean shadow line and drips rain clear of the wall. More than about 2 inches starts to look like a mushroom and invites the corner chip every time someone bumps it.
Thickness: 2 inches minimum, 3 reads better
Thin caps crack and look flimsy on anything taller than a border. On a wall people will see from the street, a 3 inch cap carries visual weight that matches the wall. On seat walls, thicker also means the cap will not rock loose under years of use.
Match or contrast, but decide on purpose
Two approaches work. Matching caps, limestone on a limestone wall, keep the wall quiet and let the landscape lead. Contrast caps, a buff cap on a gray fieldstone wall, outline the wall like trim on a house. What does not work is accidental near-match, a cap that is almost the wall color but not quite. Bring a photo of the wall, or better, a loose stone from it, and pick caps against real inventory in the yard. Buyers have been walking this ground to make exactly those calls for a long time; the Bennett Brothers of Hot Springs heritage behind the yard dates to 1972.
Ordering caps without the usual mistakes
Three numbers get a cap order right: the linear feet of wall, the wall's top width, and the count and size of any columns. From that we pull flat stock at the right depth so your mason is trimming length, not ripping width, which saves real labor time. Add roughly 10 percent for cuts and culls on snapped-edge material. Contractors capping walls every month should be doing this on a verified pro account with trade pricing and net terms. And if the wall itself is still being planned, start with our retaining wall stone guide so the cap order and the wall order arrive together.
Frequently asked questions
How thick should cap stone be?
Two inches is the working minimum for wall caps; 3 inches looks and wears better on prominent walls and seat walls. Column caps typically run 2 to 3 inches as well, in a single piece per column.
How much should a cap overhang the wall?
One to two inches per exposed face. Enough to throw a shadow line and drip water clear, not so much that corners become targets.
Do I need cap stone on a dry-stacked wall?
Structurally a dry wall drains on its own, but a cap still locks the top course, sheds most of the rain, and finishes the look. Most dry-stack walls we supply leave the yard with caps on the same trailer.
Can you match caps to my existing wall?
Usually, yes. Bring a photo and, if you can, a loose piece of the wall stone to the yard at 5643 N Hwy 7. Matching against pallets on the ground beats guessing from a screen every time.
Cap the wall before winter tests it
Measure the wall top, count the columns, and call 501-532-1905. We will size the caps, quote the material, and coordinate delivery anywhere in Garland and Saline counties. Or walk the yard at 5643 N Hwy 7, Hot Springs Village, AR 71909 and choose the exact stock. Project photos can also go through our contact page for a follow-up quote. Whether the wall behind it cost $500 or $5,000, the cap is the smallest line on the invoice and the part protecting all the rest.