Cuts eat 5–15% of the paver. The base is a volume, compacted. Edge restraint, the sand setting bed and slope to drain are why a pile of stone on the lawn is not a patio — they are named here because they are not in the two numbers.
Waste + basethe two lines a naive area box skipsPaver sq ft × (1 + waste). Base cu yd = area × (depth ÷ 12) ÷ 27 × 1.2 compaction. Compaction factor is editorial, same as the gravel tool.
On 200 sq ft, 10% waste, 6 inches of base: 220 sq ft of paver and about 4.4 cubic yards of base after compaction. Then you still need edge restraint, bedding sand and a slope that drains. HyreYard does not lay pavers.
Surface, waste, base depth
Two numbers, and a list of what they skip. Nothing is emailed.
—Paver area to order
—Base volume
—Not included
What this assumed—
Geometry plus a labelled compaction allowance. HyreYard does not lay pavers.
Start here
Pavers do not fail. Bases fail.
A sunken, rocking, weed-filled patio is almost never caused by the pavers. It is caused by what is under them and what is around them — and all of it was buried before anybody saw the finished surface, which is why it is the easiest place in hardscaping to win a bid by leaving things out.
The assembly is four things, and the paver is the least demanding of them. A compacted subgrade, a compacted aggregate base of a published thickness, a screeded bedding layer of a specified sand, and an edge restraint that stops the whole thing spreading. The paver sits on top of that and does very little except be walked on.
Which is exactly why the cheapest bid is usually the thinnest base. Base stone, its haul, its excavation and its compaction time are a large fraction of the cost of a patio and are completely invisible in the finished product. Two quotes that both say "prepare base and lay pavers" can differ by four inches of stone and half a day of compaction, and the only way to tell is to ask for the number.
The failure is slow, which protects the person who caused it. An under-built patio looks perfect for one season, develops a dip in two or three, and rocks under a chair leg by five. By then it reads as ordinary wear rather than as a base that was never there. The warranty, if there was one, has usually expired.
The four published numbers to put in a quote
Source facts, all from ICPI Tech Spec 2 — Construction of Interlocking Concrete Pavements. Copy these into your scope document and give the identical document to every bidder. That single step converts three incomparable proposals into three prices for one job.
The single most useful reading here: a patio on poor soil wants the same base as a driveway on good soil. Soil, not use, is often the bigger term.
The element
The published requirement
What its absence means
Base thickness
4 in compacted for patios and walkways over well-drained soils; 6 in for residential driveways. "In colder climates, continually wet or weak soils will require that bases be at least 2 to 4 in. (50 to 100 mm) thicker."
The largest hidden variable in the price. A quote with no base number cannot be compared with one that has a number, and the difference is not cosmetic.
Compaction
Subgrade and base to at least 98% of standard Proctor density, ASTM D698 for pedestrian areas and residential driveways; modified Proctor density, ASTM D1557 or AASHTO T180 for vehicular. Placed in 4–6 in lifts.
Stone that has been dumped and levelled rather than compacted in lifts. Passes the boot test on the day, settles unevenly within a few seasons.
Bedding sand
ASTM C33 or CSA A23.1 FA1 concrete sand, screeded to an uncompacted nominal 1 in. "Masonry sand for mortar should never be used for bedding, nor should limestone screenings or stone dust."
Stone dust or screenings used because they screed beautifully. Named in the standard as what not to use; they hold water and freeze.
Edge restraint
"A minimum of 1 in. (25 mm) vertical restraining surface should be in contact with the side of the paver to adequately restrain it."
The patio spreads at the perimeter, joints open, and the failure works inward from the edge. This is the cheapest item on the list and the one most often value-engineered out.
Read as the PDF republished by an ICPI member distributor. ICPI has since merged into the Concrete Masonry & Hardscapes Association and icpi.org redirects to masonryandhardscapes.org, so the member mirror is the copy we were able to retrieve on 5 September 2026.
Waste is a function of the pattern, not a flat ten percent
Ten percent is a convention, not a calculation. Waste comes from cutting, and how much cutting there is depends on the pattern you chose and the shape of the area — which is a decision you can still change while it is cheap to change it.
Illustrative. These stack: a herringbone inside a curved edge is not eighteen percent, it is the pattern allowance plus the edge allowance. Ask your installer what they want ordered.
Where the waste comes from. Every unit that meets an edge is cut, and the offcut is reusable only if it is large enough to start another course. A running bond in a rectangle produces offcuts that are usable at the opposite edge. A herringbone against a curve produces triangles that fit nowhere.
So the geometry dominates. A square patio in a simple pattern genuinely wastes less than ten percent. The same area laid diagonally, with a curved edge and a circular feature, comfortably exceeds fifteen. Ordering ten percent for the second case means a second order — which is where the real problem starts.
Batch variation is the reason to over-order, not cost. Concrete pavers are pigmented and cured in production runs, and runs differ in shade. A second order arrives from a different run and will not match. On a patio, in daylight, that is highly visible and there is no fix short of relaying the area. The cost of an extra pallet is trivial against that.
Keep the spares. A dozen units from the original run, stacked out of the way, is what turns a future utility trench, a cracked unit or a settled corner into an invisible repair rather than a visible patch. It is the cheapest insurance in the whole project and it needs to be decided at ordering time, because it cannot be decided later.
And cut quality is a real line item. Cuts made with a wet saw against a marked line look deliberate; cuts made with a splitter or a grinder freehand do not. On a patio with a lot of perimeter, this is a visible difference in the finished job and it is worth asking which is being used.
Why the base volume is bigger than the hole
The base number this tool gives you carries a compaction allowance, and that allowance is editorial. It is labelled here rather than folded silently into the arithmetic.
Illustrative, and the allowance is editorial. Turn it off if you are buying a pre-compacted or already-processed product.
Our factor is ×1.2, and it is a judgement. Compaction is a real volume change and ICPI requires the base to reach 98% of standard Proctor density. The ratio between the loose volume you buy and the compacted volume you end up with depends on gradation, moisture and the compactor, and there is no published national figure for "crushed stone". Twenty percent is our planning allowance, not a measurement of your quarry.
What is not a judgement is that compaction is real and specified. ICPI Tech Spec 2 — Construction of Interlocking Concrete Pavements calls compaction of the soil subgrade critical to performance and sets the base to at least 98% of standard Proctor density, ASTM D698 for patios and residential driveways. Loose stone spread to six inches is not a six-inch base; it is a five-inch base once it has been made to do its job, and the missing inch has to come from somewhere.
Lifts are where the corner gets cut. The document specifies spreading and compacting in 4–6 in lifts using 7,000 lbf (31 kN) reversible plate compactors, with thinner lifts for lighter machines. A single eight-inch dump compacted from the top gives you a firm surface over loose material, which is precisely the condition that produces a dip two years later.
And frozen material is out. "Frozen or saturated sand should not be installed, and frozen material should not be compacted." A patio built in a cold snap because the crew had a gap in the schedule is a patio built against the standard.
The four things that are not in either number
The calculator gives you a paver quantity and a base volume. Here is what stands between those two numbers and a patio that is still flat in ten years.
Slope, and which way
ICPI Tech Spec 2 — Construction of Interlocking Concrete Pavements states plainly: "Slopes should be a minimum of 1.5%." That is a minimum, and it has to run away from the house. A patio that drains toward a wall is a water-management problem with a stone surface on it.
A flat-looking patio is not flat. The slope has to be built into the subgrade and carried through every layer — you cannot add it at the bedding stage, because the bedding layer is a nominal inch and there is nowhere for the fall to go.
Where the water goes instead
A new patio is a new impervious surface. The EPA notes that in developed areas "much of the land surface is covered by buildings, pavement and compacted landscapes. These surfaces do not allow rain and snow melt to soak into the ground which greatly increases the volume and velocity of stormwater runoff". Rain that used to soak in where it fell now arrives somewhere else, faster.
Where it arrives is a decision you are making whether or not you think about it: a lawn that becomes boggy, a neighbour’s boundary, or a foundation. Establish the destination before the excavation, not after. The EPA page states the mechanism and does not publish a runoff percentage. We do not publish one either.
The subgrade under all of it
USDA NRCS Web Soil Survey gives you the mapped soil at your address, its drainage class and its hydrologic soil group, free, in about five minutes. It is the cheapest useful thing a homeowner can do before buying hardscape.
It matters because the published base minimums assume well-drained soils, and the same document adds 2–4 in on continually wet or weak ones. On a Group D clay you are building a different patio from the one on a Group A sand. A parcel-level lookup of the mapped soil, its drainage class, its hydrologic soil group and its shrink-swell potential. It is free, it takes about five minutes, and it is the cheapest useful thing a homeowner can do before buying hardscape. It is a survey map, not a site investigation of your lot.
Joints, and what fills them
Joint sand is what transfers load between units — it is the mechanism that makes a field of separate pavers behave as a surface. Empty joints are not a cosmetic issue; they are a structural one, and they are the entry point for the weeds people blame on the pavers.
Polymeric sands harden and resist washout, which helps on slopes and around edges, and they are also the material most often installed wrong — the surface has to be dry, swept genuinely clean, and watered exactly as the manufacturer states. Follow that data sheet rather than a general habit.
The order of work, and where it goes wrong
Everything expensive to fix happens in the first five steps, and everything visible happens in the last two.
1
Call 811 before you dig
Free, legally protected in every state, and it takes a few working days. A patio excavation is deep enough and wide enough to find services. This step is not advice, it is the law in every state.
2
Establish the finished level and the fall
Where the surface meets the door threshold, the lawn and any existing hard surface, and which way the water runs. Minimum 1.5% away from the house. Everything below is subtraction from this.
3
Excavate to full depth across the whole area, plus overdig
Base depth plus bedding plus paver thickness. Excavate wider than the finished patio so the base extends past the edge — the edge restraint has to sit on compacted base, not on soil.
4
Compact the subgrade, and consider separation fabric
A geotextile between subgrade and base stops fine soil pumping up into the stone and destroying its gradation. It is inexpensive relative to the base above it and it is the difference between a base that lasts and one that slowly turns into soil.
5
Build the base in lifts, compacting each one, checking depth with a tape
4–6 in lifts. Measure the depth at several points after each pass rather than judging by eye. Pay particular attention next to edges and any structures — that is where compaction is hardest and where failure starts.
6
Install the edge restraint on the base, then screed the bedding
At least 1 in of vertical contact with the paver. Then screed the bedding sand to an uncompacted nominal inch — and do not use it to level an uneven base, because "If there is an uneven base, the bedding sand should not be used to compensate for it. Over time, unevenness in the bedding sand will reflect through to the surface."
7
Lay, cut, compact and joint
Lay from a straight reference line, keep the pattern true, cut against a marked line, then compact the pavers into the bedding and fill the joints. Sweep and re-fill joints again after the first heavy rain; they will have settled.
What a good paving quote says
The highest-value section on this page. A quote containing these six lines can be compared with another quote containing them. A quote without them cannot be compared with anything.
A compacted base depth, in inches, with the number of lifts
Not "prepare base". A number, and the lift count. 4 in is the published patio minimum on well-drained soil, and your soil may not be well-drained.
The compaction standard being worked to
98% of standard Proctor density, ASTM D698 is what the industry document specifies for a patio. Asking the question tells you quickly whether you are talking to someone who has read it.
The bedding material, named to a gradation
ASTM C33 or CSA A23.1 FA1 concrete sand, at an uncompacted nominal 1 in. If the answer is stone dust or screenings, the standard names those specifically as what not to use.
The edge restraint type and how it is fixed
Which product, spiked into what, and sitting on base rather than on soil. This is the least expensive line on the quote and the one whose absence is most reliably fatal.
The direction and percentage of fall, and where the water goes
A named destination for the runoff. "It will find its way" is the answer that precedes a wet basement or a boundary dispute.
A quote that prices only per square foot of paver
The paver is the cheapest and least consequential part of the assembly. A per-square-foot price with no base specification behind it is a price for the visible half of the job.
Any bid that does not mention excavation depth or spoil removal
Six inches of base plus bedding plus paver over a decent-sized patio is a great deal of excavated soil, and it has to go somewhere. If disposal is not in the quote, it will be in a change order.
The vocabulary, so the quote can be read
Subgrade
The native soil under everything. Compacted before any stone goes on. Its drainage class is what decides whether the published minimum base is enough.
Base course
The compacted dense-graded aggregate that spreads load. Published as a minimum thickness by use and soil, and the largest hidden variable in a price.
Lift
One layer of base placed and compacted before the next. Compacting eight inches in one pass compacts the top two and leaves the rest loose.
Bedding course
The screeded ASTM C33 or CSA A23.1 FA1 concrete sand layer the pavers are set into, at an uncompacted nominal 1 in. A setting layer, never a levelling layer.
Edge restraint
The perimeter element that stops lateral spread. ICPI Tech Spec 2 — Construction of Interlocking Concrete Pavements calls for a minimum 1 in of vertical restraining surface against the paver.
Joint sand
What fills between units and transfers load between them. Empty joints are a structural problem before they are a weed problem.
Interlock
The mechanism by which separate units behave as a surface: vertical, rotational and horizontal, achieved through joint sand, laying pattern and edge restraint together. Lose any one and the other two do not compensate.
Geotextile separation fabric
Fabric between subgrade and base that stops fine soil migrating up into the aggregate. Not the woven weed fabric sold in garden centres.
Overdig
Excavating and basing wider than the finished surface so the edge restraint bears on compacted base rather than on soil. Cheap at the time, impossible to add later.
Proctor density
A laboratory reference density for a material at optimum moisture. Field compaction is expressed as a percentage of it. Standard (ASTM D698) and modified (ASTM D1557) are different references and not interchangeable.
What this calculator cannot do
Real blind spots. Two numbers cannot describe a four-layer assembly and this page would rather say so than imply otherwise.
It cannot choose your base depth. Depth follows use, soil and climate. The published minimums are on this page so you have a defensible floor, but the tool takes what you type and does not know what it is being built on.
It cannot see your soil, your frost depth or your water table. All three change what a durable assembly looks like, and all three are local. The soil part is a free lookup we point at and cannot do for you.
It is not a structural design. Anything carrying a vehicle beyond a domestic driveway, anything retaining soil, and anything supporting a structure is engineering. A quantity is not a design.
It does not know your pattern. Waste is a function of the layout and the edge shape, and the range is wide enough that a flat ten percent is wrong at both ends. The chart above is illustrative planning judgement, not measured data.
It does not price anything. No paver price, no base price, no labour rate, no regional multiplier. HyreYard holds no dataset of hardscaping jobs, bids or prices, and will not manufacture one to look authoritative.
And we do not lay pavers. HyreYard does not perform hardscaping work, does not rank contractors and takes no referral fee from anyone who does — which is why this page is free to tell you that the base you cannot see matters more than the stone you chose. Figures verified 5 September 2026.
Questions this calculator answers
How many pavers do I need?
The area of the finished surface plus waste for cuts. Patterns with diagonals waste more. 10% is a start, not a law.
How much base is under a patio?
Often 4 to 8 inches of compacted aggregate, plus a sand setting bed. Type the depth your installer specified. This page will not invent a structural section.
Web Soil Survey (USDA Natural Resources Conservation Service, retrieved 2026-09-05. Free parcel lookup of the mapped soil, its drainage class and its hydrologic soil group. The published base minimums assume well-drained soils, so this is the lookup that tells you whether they apply. A survey map, not a site investigation.)
Nonpoint Source: Urban Areas (US Environmental Protection Agency, retrieved 2026-09-05. Cited for the mechanism by which impervious surfaces increase the volume and velocity of runoff. The EPA page states the mechanism and publishes no runoff percentage; neither do we.)
Related
Patios and walkwaysWhat the base depth, the bedding and the edge restraint actually are, and how to tell whether a quote names them.
Patio size plannerHow big the sitting area wants to be, before you order stone.
Gravel calculatorIf you already know the base area and depth as a pile of stone.