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Pour a Concrete Patio: The Complete Project Guide
Published July 19, 2026
A patio can be built two genuinely different ways — a poured concrete slab or a paver system over a gravel base — and picking the right calculator depends on which path you're taking, since they use different materials and different volume formulas entirely. This guide lays out both paths so you choose the right one before ordering anything, rather than mixing calculators meant for different approaches.
Poured path: concrete slab calculator. Paver path: gravel calculator for the base layer, paver calculator for the units themselves, and sand calculator for bedding and joint sand.
Choosing poured concrete vs. pavers
A poured slab is a single continuous surface, generally faster to install for a simple rectangular shape and easier to keep weed-free, but harder to repair invisibly if it cracks (a crack in one section of a monolithic slab is visible across the whole surface) and it's a one-shot pour — mistakes in forming or finishing are locked in once it cures. Pavers cost more in labor to lay individually but allow easier spot repairs (lift and replace individual units), handle ground movement better without a visible crack, and support more design flexibility (patterns, curves, mixed materials).
See concrete bags vs ready-mix for the decision framework on how to source concrete if you go the poured route on a larger patio.
Poured path: forming, reinforcement, and the pour
Size the concrete slab calculator from patio area and thickness (4 inches is a common patio slab thickness, thicker if it will see vehicle load). Build forms level and well-braced before ordering concrete — forms have to hold the wet concrete's weight and shape until it cures, and a form failure mid-pour is a serious problem, not a minor one. Wire mesh or rebar reinforcement is standard for crack resistance, and a compacted gravel sub-base under the slab (similar to the paver path's base layer) helps drainage and reduces settling.
Plan control joints (scored lines that give the slab a predetermined place to crack rather than cracking randomly) at regular intervals before the pour, typically spaced at roughly 2-3 times the slab thickness in feet — skipping control joints doesn't prevent cracking, since concrete shrinks slightly as it cures regardless, it just means the crack happens wherever the slab is weakest rather than somewhere planned and less visually noticeable.
Paver path: base, pavers, and joint sand
Size the compacted gravel base with the gravel calculator (typically 4-6 inches deep for a patio), then the field pavers with the paver calculator at your chosen pattern's waste percentage — see paver patterns and waste guide for how much running bond vs. herringbone actually differs. Finish with bedding and joint sand from the sand calculator, and install edge restraints around the full perimeter to keep the pattern from spreading over time.
Compact the gravel base in multiple thin lifts rather than one thick pass — a plate compactor typically only effectively compacts the top few inches of loose material per pass, so a 5-inch base built and compacted as one loose layer often ends up less dense than the same 5 inches built in two compacted lifts.
Drainage and slope for either path
Whichever path you choose, the finished patio surface needs a slight slope away from the house — typically around 1/8 to 1/4 inch per foot — so water runs off rather than pooling against the foundation or the patio surface itself. This slope has to be built into the base layer (gravel or compacted subgrade) before the final surface goes down; it's essentially impossible to correct after a slab has cured or pavers are fully set.
Excavation depth: the step both paths skip in a quick estimate
Total excavation depth needs to account for the full assembly, not just the visible finished surface — a paver patio's excavation typically needs to be the base depth plus bedding sand depth plus paver thickness (often totaling 7-9 inches for a standard residential patio), and a poured slab's excavation needs the gravel sub-base depth plus the slab's own thickness. Underestimating total excavation depth is a common planning miss that shows up as the finished patio sitting higher than intended relative to a doorway threshold or surrounding grade.
Working around existing structures
A patio built against the house needs its slope and finished height planned relative to the house's siding and any door thresholds — most codes and best practice call for keeping siding a minimum clearance above the finished patio surface (commonly a few inches) to avoid moisture wicking into the siding material, which is easy to overlook when focused mainly on the patio's own drainage slope.
Tools and materials checklist
- Stakes, string line, and a line level for establishing the patio's outline and slope.
- A plate compactor for the gravel base (paver path) or subgrade (poured path), rented if not owned.
- For poured concrete: form boards, stakes, a screed board, a bull float, and an edging/jointing tool.
- For pavers: a rubber mallet, a paver-cutting saw or splitter, and edge restraint spikes.
- Landscape fabric under the gravel base (paver path) to slow weed growth from below, if desired.
- A shovel, wheelbarrow, and hand tamper (or rented plate compactor) for excavation and base prep on either path.
Maintaining the finished patio
A poured slab benefits from periodic sealing (frequency depends on climate and traffic, often every few years) to reduce staining and water absorption, and any cracks that develop over time should be filled promptly to keep water from working its way in and worsening the crack through freeze-thaw cycles. A paver patio's main ongoing maintenance is joint sand top-up and occasional re-leveling of any individual paver that settles unevenly — a real advantage of the paver approach, since a settled paver can be lifted and reset without the all-or-nothing repair a cracked slab section requires.
Planning for future access needs
If underground utilities, irrigation lines, or a future addition might need access beneath the patio, this is worth thinking through before committing to either path — a paver patio allows lifting a section for access and resetting it afterward with minimal visible disruption, while a poured slab generally requires cutting and patching, which is far more visible and labor-intensive for the same access need.
FAQ
Which is cheaper, a poured patio or pavers?
Materials cost is often comparable or slightly favors poured concrete for a simple shape, but labor and long-term repair cost tend to favor pavers, since a cracked slab section is harder to repair invisibly than lifting and replacing a few individual pavers.
Does a poured patio need a gravel base too?
Yes — a compacted gravel sub-base under a poured slab improves drainage and reduces the chance of the slab settling or cracking from an unstable subgrade, even though the finished surface is a single continuous pour rather than individual units.
Can I switch from a poured plan to a paver plan partway through, or vice versa?
It's possible early on (before the base or forms are built), but the base preparation genuinely differs between the two — a poured slab's subgrade doesn't need the same depth or compaction spec as a paver base — so it's worth firmly deciding the approach before any excavation begins rather than partway through.
How long before I can use a new poured patio?
Concrete typically reaches enough strength for light foot traffic within about a week, but full cure strength (safe for furniture and heavier use) commonly takes closer to a month — check your specific mix's guidance and avoid heavy loads or dragging furniture across it before then.
How deep should I excavate for a paver patio?
Total excavation is typically base depth (4-6 inches) plus bedding sand depth (about 1 inch) plus paver thickness, commonly landing around 7-9 inches total for a standard residential installation — always confirm against your specific paver thickness and base spec rather than assuming a flat number.
Do I need a permit for a patio?
It varies by jurisdiction and sometimes by the patio's size or whether it's attached to the house — many areas don't require a permit for a simple ground-level patio, but it's worth a quick check with your local building department before starting, especially for a larger project or one that changes drainage patterns on the property.
Should I seal a paver patio the same way as a poured slab?
Paver sealing is optional and mainly cosmetic/protective (enhancing color, reducing staining, sometimes helping polymeric sand stay locked in the joints), whereas a poured slab's sealing has a somewhat larger role in reducing water absorption and staining across one continuous surface — both are worth doing, but neither is strictly required the way base compaction and slope are.
Can I add a fire pit or outdoor kitchen feature to a patio after it's built?
On a paver patio, yes relatively easily — lift the pavers in the area needed, excavate and build the feature's own foundation, and reset the surrounding pavers; on a poured slab, adding a feature after the fact generally means cutting into the existing concrete, which is more disruptive, so planning known future features into the original patio layout is worth doing on the poured path specifically.
Does patio slope direction matter if the patio sits right against the house foundation?
Yes, significantly — the slope needs to carry water away from the foundation, not toward it, so the high edge of a patio adjoining the house should be at the house side with a consistent fall outward, since even a well-built patio can contribute to foundation moisture problems if it's graded the wrong direction.