Concrete & Masonry
Concrete, paver, gravel
Concrete work starts with one number that trips people up: volume. It isn't an area - it's area times thickness - so a slab an inch too thick or too thin changes the order by a full wheelbarrow-load. Get the volume right and everything downstream (how much to order, bags versus ready-mix, what it costs) falls into place.
These tools handle both halves. The volume calculator turns your length, width and thickness into cubic yards - or 60/80 lb bags - with a waste allowance so you don't run dry mid-pour. The cost calculator then prices the job: concrete is cheap by the yard, but forms, rebar, finishing and labor are where the real money goes.
Guides
Frequently asked questions
How do I calculate how much concrete I need?
Multiply the area by the slab thickness, then convert to cubic yards: length × width × depth in feet, divided by 27. Add about 10% so an uneven subgrade or a bit of spillage doesn't leave you short - you can't pause a pour to fetch more. The concrete calculator does the conversion and the waste for you.
Bagged concrete or ready-mix delivery?
Bags suit small jobs - fence posts, a small pad, repairs - up to roughly a quarter of a cubic yard. Beyond that, ready-mix delivered by truck is cheaper and far less work than mixing dozens of bags by hand. A cubic yard is about 45 × 80 lb bags, so the crossover comes fast.
How thick should a concrete slab be?
Four inches is standard for patios, walkways and shed floors; step up to five or six inches for driveways and anything that carries vehicles. Thicker slabs need more concrete and usually rebar or wire mesh - work both into your volume and your budget.
What drives the cost beyond the concrete itself?
The mix is a small part of the bill. Formwork, a compacted gravel base, rebar or mesh, the finish (broom, stamped or polished) and labor typically cost more than the concrete. The cost calculator uses installed national-average rates, so the estimate reflects the whole job - not just the mud.