The calculator above opens on a patio with exposed aggregate selected, at an example rate of $13 per square foot. That sits between broom at the example $9 and stamped at $16, which is exactly where the finish lives: decorative money, but earned in a different way than stamping.
The wash-off is the job
With aggregate, the skill is in the timing. Surface retarder goes down after the pour, and the crew comes back to wash off the top layer of paste at exactly the right point in the set. Wash too early and you tear stones out of the surface. Wait too long and the paste wins, and now you are grinding or acid-washing to rescue the finish. Weather moves that window around, so an aggregate pour owns the crew’s schedule for the day in a way a broom pour does not. That labor reality is why it prices above plain flatwork even with no mats or color hardener involved.
The rock sets the look and part of the cost
The exposed stone is the finish, so the mix design is a real decision, not a footnote. Local round pea gravel is the budget path. A specified decorative rock, or seeding chosen stone onto the surface by hand, adds material cost and labor that belongs in your rate. Settle the rock choice with the customer before you price, because switching aggregate after the quote reprices the whole job.
Where aggregate beats stamped
Three places. Grip: the exposed stone has real texture underfoot, which is why pool decks lean this way. Repairs: there is no pattern to match, so a future patch or an added section blends far better than a stamped repair ever will. And wear: the surface hides broom marks, stains, and traffic better than a smooth colored slab.
Run the numbers on a 15 by 20 pool deck surround, which is 300 square feet. At the example aggregate rate of $13 that is $3,900, against $2,700 broom and $4,800 stamped. For the plain-finish version of the same job, see the concrete patio cost calculator, and for how to set the underlying rate itself, read what to charge per square foot for flatwork.
Those are example rates, not your rates. PriceDesk runs this calculator with your own numbers on your phone, free for 14 days, no card to start.