How big should a patio be?

Big enough for the furniture you use with the chairs pulled out, plus room to walk behind them, plus any grill. Measure your own furniture on the lawn; HyreYard publishes no per-seat rule.

How much walkway space do I need?

Walk behind a pulled-out chair and measure the band you want clear. Type that as the walkway; the planner adds it to every side.

How much slope does a patio need?

ICPI Tech Spec 2 says slopes should be at least 1.5%. That is about 0.18 inches of fall per foot, running away from the house.

Do I need a permit for a patio?

Often not for flatwork at grade, where the model exemption is adopted: not more than 30 inches above adjacent grade and not over a basement. Zoning, HOA and easements still apply. Ask your building department.

What comes after the size?

Take the area to the paver calculator for pavers and base, then add the bid to the landscaping cost estimator.

Does this work for a hot tub or a roofed patio?

No. A spa adds weight, wiring and clearances, and a roof is a structure. Plan them with a designer and your building department.

HyreYard tools

Patio size planner

Set your table and chairs out on the lawn, pull the chairs back, and measure. Add the walkway you want and any grill zone.

1.5% minimum slope for a paver patio ICPI Tech Spec 2, Construction of Interlocking Concrete Pavements: “Slopes should be a minimum of 1.5%.” That is about 2.2 in of fall across 12 ft, away from the house.

A patio should be the furniture zone with chairs pulled out, plus a walkway band on each side, plus any grill area. A 12 × 10 ft zone with a 3 ft walkway and a 30 sq ft grill area is 318 sq ft. Slope it at least 1.5% away from the house.

Work out your patio size

Geometry on your measurements. Nothing is stored or emailed.

— Patio area

— Dimensions

— Minimum fall

What this assumed —

A planning area, not a slab design. Take it to the paver calculator next.

How to measure

Measure the furniture, not the lawn

Put your table and chairs on the lawn where the patio will go, and measure what they actually take up.

1
Set the furniture out
Table, chairs and any lounger, arranged the way you will use them.
2
Pull the chairs out
Slide each chair back as if someone is getting up. That is the furniture zone.
3
Measure length and depth
Length runs along the house; depth runs out from it. Use a tape, in feet.
4
Decide the walkway
Walk behind a pulled-out chair and measure the band you want clear on each side.
5
Add other zones
Measure the grill, a planter or a path to the door in square feet and add it.

Two patios, run through the planner

A dining patio with a grill

A 12 × 10 ft furniture zone, a 3 ft walkway on every side, and a 30 sq ft grill area: 18 × 16 ft plus 30 sq ft is 318 sq ft. At ICPI’s 1.5% minimum, the 16 ft depth needs at least 2.9 in of fall.

A bistro table, no walkway

A 7 × 7 ft zone with no walkway is 49 sq ft, with at least 1.3 in of fall across it.

Measurements are examples; type yours. The area goes into the paver calculator next.

A patio has to slope

A dead-level patio holds water. ICPI Tech Spec 2 sets a minimum slope for that reason.

The figure. ICPI Tech Spec 2, Construction of Interlocking Concrete Pavements: “Slopes should be a minimum of 1.5%.” That is 2.2 in of fall across 12 ft, our arithmetic on the published percent.

It is a minimum. Bedding settles unevenly and pavers shift slightly. A patio built exactly at the minimum can have low spots below it.

Standing water does damage. It works into the joints and, in a freezing climate, freezes and thaws at the surface. Water that reaches the base softens what the patio stands on.

Choose the direction. Away from the house first. Then ask where the water goes past the edge.

Where the water goes after it leaves the patio

The slope moves water off the surface and delivers it to the strip along the low edge.

A new hard surface. EPA: “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 soaked into that ground now runs to the low edge.

The soil decides what happens next. NRCS group A soils are low runoff; group D soils are high runoff. On a group D soil, “it will soak away” is not a plan. Web Soil Survey tells you which you have, free.

Keep it off the house and the neighbor. Never direct the fall toward a foundation. Rules on sending runoff onto a neighbor’s land vary by state; find out before you build.

Options. A smaller patio. A split fall so no one edge takes it all. A gravel strip or planted bed along the low edge. A designed drain to a real outlet where the soil will not take it.

What goes under the patio, from ICPI Tech Spec 2

Size is the first decision. These figures decide whether it lasts; the paver calculator works out the volumes.

Layer	ICPI figure
Compacted base	4 in minimum under a patio on well-drained soil; 2 to 4 in more on wet or weak soil in cold climates.
Compaction	98% of standard Proctor density, ASTM D698, in 4 to 6 in lifts.
Bedding sand	ASTM C33 or CSA A23.1 FA1 concrete sand, about 1 in, not used to level the base.
Edge restraint	At least 1 in of vertical contact with the paver.
Slope	At least 1.5%.

A patio at grade may need no building permit

The model exemption is narrow, and other rules still apply.

The model list, Texas Windstorm Insurance Association Building Code, 2024, section 105.2, read on 5 September 2026, exempts: “Sidewalks and driveways not more than 30 inches (762 mm) above adjacent grade, and not over any basement or story below and are not part of an accessible route.”

Read the limits. A patio built up on fill to level a slope can pass 30 inches above grade, and then it is not exempt.

The closing sentence. “Exemptions from permit requirements of this code shall not be deemed to grant authorization for any work to be done in any manner in violation of the provisions of this code or any other laws or ordinances of this jurisdiction.”

Still ask about: lot coverage or impervious-surface limits, setbacks, HOA covenants, easements and any local stormwater rule. One call to the building department can cover them if you ask each one.

What a patio bid should say

The area and its dimensions
So you can check them against what you measured here.
Base depth in inches, and the soil it assumes
ICPI’s minimum is 4 in on well-drained soil.
Compaction method and lifts
4 to 6 in at a time.
Bedding material, by name
ASTM C33 or CSA A23.1 FA1 concrete sand.
Slope as a percent and a direction
At least 1.5%, away from the house.
Edge restraint as its own line
Which product and how it is fixed.
A price per square foot with no base spec
Ask what sits under the surface.

What this planner cannot see

Your lot. Trees, doors, downspouts, slope and setbacks cut the rectangle you measured. Walk the site.

Structure. It is an area and a fall, not a slab design. A roof, a spa or a raised patio is a different job.

Smaller can be better. A patio sized to how you actually sit costs less and sheds less water. HyreYard does not build patios.

Questions this calculator answers

How big should a patio be?: Big enough for the furniture you use with the chairs pulled out, plus room to walk behind them, plus any grill. Measure your own furniture on the lawn; HyreYard publishes no per-seat rule.
How much walkway space do I need?: Walk behind a pulled-out chair and measure the band you want clear. Type that as the walkway; the planner adds it to every side.
How much slope does a patio need?: ICPI Tech Spec 2 says slopes should be at least 1.5%. That is about 0.18 inches of fall per foot, running away from the house.
Do I need a permit for a patio?: Often not for flatwork at grade, where the model exemption is adopted: not more than 30 inches above adjacent grade and not over a basement. Zoning, HOA and easements still apply. Ask your building department.
What comes after the size?: Take the area to the paver calculator for pavers and base, then add the bid to the landscaping cost estimator.
Does this work for a hot tub or a roofed patio?: No. A spa adds weight, wiring and clearances, and a roof is a structure. Plan them with a designer and your building department.

Sources and methodology

Figures dated September 5, 2026. Last reviewed September 18, 2026.

ICPI Tech Spec 2, Construction of Interlocking Concrete Pavements (Interlocking Concrete Pavement Institute (© 1995 ICPI, revised February 2020), retrieved September 5, 2026). Minimum slope, base, compaction, bedding and edge figures.
Work exempt from permit (Model administrative provisions, read in Texas Windstorm Insurance Association Building Code, 2024, section 105.2, retrieved September 5, 2026). The flatwork exemption and its limits.
Nonpoint Source: Urban Areas (US Environmental Protection Agency, retrieved September 5, 2026). Hard surfaces increase the volume and speed of runoff.
Web Soil Survey (USDA Natural Resources Conservation Service, retrieved September 5, 2026). Hydrologic soil group for your lot.

Paver calculator Take this area next: pavers and base.
Patios and walkways What a patio job includes and how to read the quote.
The base specification What a written base spec should state.
Drainage diagnostic Where the patio’s runoff will go.
Landscaping cost estimator Add the patio bid to a project budget.

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