Exposed Aggregate Calculator

Total Project Cost is proportional to Surface Area -- every cost component (concrete, retarder, sealer, and, for the seeding method, decorative aggregate and labor) is a direct per-square-foot rate, so Surface Area dominates the total more reliably than any other input: a 10% change in area moves the total by roughly the same 10%, while no other single input reaches that share of the total on its own. Exposure Depth and Method both look like they might not matter much because they're small coded selections (1-3 and 1-2), and a small nudge around their default values rounds right back to the same integer -- but each has a real, substantial effect across its actual range. Exposure Depth changes the surface retarder coverage rate (250 sq ft/gal for a light reveal down to 150 sq ft/gal for a heavy reveal, needing about 67% more retarder), the seed rate for the seeding method (1 to 3 lbs per sq ft), and the sealer coverage rate. Method changes whether seed aggregate cost applies at all (zero for integral aggregate, since the aggregate is already mixed in) and changes the labor rate (seeding requires an extra broadcast-and-roll step, at $5.50/sq ft vs.

$4.00/sq ft for integral). Waste Factor is a direct multiplier on the concrete, retarder, and sealer quantities together, so it moves Total Project Cost by roughly its own percentage. Slab Thickness only affects the concrete volume line item -- it doesn't touch retarder, sealer, or seed aggregate quantities at all, since those are all calculated from surface area alone.