How to Build a Fire Pit Base with Pavers

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Here is how to build a fire pit base with pavers. You need three layers under the pavers: a compacted gravel base, a thin layer of sand that the pavers sit on, and a drainage path so water does not pool under the fire. The sources we opened describe those layers for paver areas and for a granite fire pit kit. They do not give a single depth that fits every yard, so the numbers below are the ones the sources state, with the assumptions marked.

Quick answer

Dig deep enough for a base of about 5 inches of compacted gravel, about 1.5 inches of sand, and the thickness of your pavers. The Iowa State article uses about 10 inches of total excavation for 3.5-inch pavers.
Compact the soil, then the gravel in at least two passes at right angles. Check that the base is level before adding sand.
Slope the surface away from the pit and any building, about 2 inches of drop every 8 feet according to the Iowa State article.
If you use a fire pit kit, follow its installation guide first. The Polycor guide calls for a 4 to 6 foot circle at least 6 inches deep, with a crushed stone drainage hole in the center.

What the sources cover, and what they do not

The Iowa State Yard and Garden article, “Installing Concrete Pavers, Part Two,” describes a paver patio installation from 1995. It covers excavation, gravel base, sand bed, paver setting, and joint sand. It does not describe fire pits. The Polycor Round Fire Pit Installation Guide describes how to build the base and the fire ring for one granite kit with a metal insert. It does not describe pavers, and it applies to that product. We used both because the base steps overlap: the paver article explains a general paver base, and the kit guide explains how a fire pit base should drain and how it is filled.

Neither source gives a clearance distance from the fire to a building, a fence, or a deck. Those numbers come from the fire pit maker and from local code, so check both before you dig.

Step 1: Lay out the area and plan the slope

Stake out the area and mark the grade with string tied between the stakes. The Iowa State article says that if the paving is near a house or another building, the grade should slope away from the building to ensure proper drainage. It gives a slope of a 2-inch drop for every 8 feet of length.

The Polycor guide sets the size of the base for its kit: a circular area about 4 to 6 feet in diameter. The guide’s finished kit uses a 30-inch inside diameter ring, so a 4 to 6 foot circle leaves room for the stone border around it. If you are building a square or rectangular pit, the guide’s square version uses the same base steps, but the size of your pit sets the size of your excavation.

Plan the paver area so the pit has a clear ring of pavers around it. A single ring of pavers is simpler to level than a full patio, and it is easier to keep the base consistent when the pit is only one part of the setting.

Step 2: Dig out the soil and the sod

Remove the sod and the soil inside the staked area. The Iowa State article says to dig out enough soil to allow for a base, a sand layer, and the paver thickness. In its climate, the author digs out 10 inches in total: 5 inches of base, 1.5 inches of sand, and about 3.5 inches for the paver. The article notes that many pavers are about 3.5 inches thick, so the depth depends on the paver you buy. Measure your own pavers before you dig.

The article also says that preparing the paver bed is the most important step, and that performance depends on the quality of the soil and the base material. Level the soil with a rake after digging.

The article suggests renting a flat-plate vibrator for compacting the soil and the gravel. The goal is a firm, even surface with no soft spots.

Step 3: Compact the soil and build the gravel base

Compact the soil with at least two passes at right angles. The Iowa State article says this removes air pockets. Then add the base material. The article says the most common base material is quarried gravel, 3/4 inch and smaller. It also says that if the area will carry vehicle traffic, the fines in the gravel, the particles that pass through a Number 200 sieve, should be kept between 5 and 11 percent. That keeps the surface from settling and heaving. A fire pit with no vehicle traffic may not need that range, but the article’s guidance is the one we opened.

Lay the gravel in a layer of about 5 inches and compact it with at least two passes of the vibrator. The article says the final depth of the base should not vary by more than plus or minus 1/2 inch over a 10-foot length. Check the base with a straightedge or a level before you add sand.

The article warns against fixing a poor base with sand. Filling low spots with sand is a common construction error. The sand layer should not be used to correct a base that is not level. The article says that areas with more than 1.5 inches of sand will result in a washboard surface.

Step 4: Add the sand bed and screed it level

Once the gravel is level, lay two lengths of galvanized pipe about 8 feet apart, parallel to each other. Spread about a 1.5-inch layer of concrete sand between them. Drag a 2×4 across the pipes to level the sand, fill low spots, and remove high spots. Then pull the pipes and fill the grooves with sand.

The article says concrete sand works well because it does not have too fine a gradation. It warns against limestone screenings or stone dust in place of sand, because they may not compact well and will degrade over time. It also says not to compact the bedding sand, because the sand needs to move into the joints between the pavers so the pavers interlock.

The Polycor guide uses processed gravel or mason sand to fill the fire pit’s interior, and it says to compact the layers every 4 inches. That is a different job from a paver bed, so do not use the interior fill as a substitute for the sand layer under the pavers.

Step 5: Set the pavers and check the joints

Start in the center of the area and work outward. The Iowa State article says this puts any trimmed pieces at the edges instead of the center. Set the pavers with about 1/8 inch between them. Every 5 feet, check the pavers with a string line. If a paver is out of line, pry it up with a screwdriver and reset it.

Install edging before you finish the joints if the edging product needs to sit under the pavers. The article says some edging should go in before the sand layer. Follow the edging maker’s instructions.

Fill the joints with dry sand. Sweep it in with a broom, then compact the pavers with at least two passes of the vibrator. The article says all joints must be full when compaction is complete.

Step 6: Build the fire pit ring and drainage

If you use a kit, place the first row of blocks around the metal ring, check that they are level, and stack the next row. The Polycor guide says the pit’s blocks may vary in thickness because the stone is natural. It recommends sorting the blocks, putting the most consistent ones on the top and middle rows, and using shims if a layer will not sit level.

The Polycor guide also calls for a drainage hole. It says to dig a hole in the center of the circle, about 12 inches in diameter and 24 inches deep, and fill it with crushed stone. If the pit sits on a paver patio, remove the pavers in the middle of the circle to dig that hole, and pitch the remaining pavers inside the circle toward the hole. The guide’s purpose is drainage, so water runs toward the hole and not under the pit.

Fill the inside of the ring with processed gravel or mason sand and compact it every 4 inches until you reach the bottom of the metal ring’s flange. The guide says that for added stability you can use landscape adhesive on the top row of blocks. It does not say to use adhesive on the paver joints.

Step 7: Use the pit safely after it is built

A finished base is not the end of the safety work. The Polycor guide says the granite blocks are protected by the sand and the metal ring, but that a fire should be kept small, because large fires and intense heat can make granite spall or crack. It says to always attend the fire, keep a hose or a bucket of water nearby, and fully extinguish the fire when you finish.

The same guide says never to use gasoline or other accelerants to start a fire. It also says not to leave children unattended around open flames or hot embers, and not to throw foreign objects into the fire.

For gas or propane pits, the fuel system and the burner are separate from the base. Follow the manufacturer’s manual for the burner, connections, and clearances. Our guide to air mixers for propane fire pits covers only that one accessory, and it does not replace the manual.

Common mistakes the sources point to

Skipping the compaction passes. The Iowa State article says at least two passes at right angles are needed in both the soil and the gravel to remove air pockets.
Filling low spots with sand. The article says this is a common construction error and that sand over 1.5 inches deep leads to a washboard surface.
Using stone dust or limestone screenings as bedding. The article says they may not compact well and will degrade with time.
Leaving no drainage. The Polycor guide calls for a crushed stone drainage hole under the center of the pit.
Using the wrong fill inside the ring. The kit guide specifies processed gravel or mason sand for the interior, compacted in layers.

How we chose

We looked for pages from a university extension and from a fire pit maker that describe a base, a sand layer, or a drainage path in enough detail to check. The Iowa State article came from a search for paver base guidance, and the Polycor PDF came from a search for fire pit installation guides. We opened both pages with curl on 2026-10-30 and checked each quoted claim against the text we extracted. We did not use search summaries as evidence. We did not rank products or compare kits.

What we could not verify

A clearance distance from the fire to a building, deck, fence, or plant. The sources we opened do not state one. Use the maker’s instructions and local code.
A base depth for a fire pit that sits on a concrete slab. Our sources cover gravel and paver bases and a granite kit, not slabs.
Whether the 1995 Iowa State depth numbers suit your soil. The article says its numbers are for “our part of the country,” and the sources we opened do not say which climate or soil that covers.
How long the base lasts. The article says pavers require little maintenance when properly installed, but it does not give a service life.

Frequently asked questions

How deep should the base be for a fire pit with pavers?

The Iowa State article uses 5 inches of compacted gravel plus about 1.5 inches of sand, with pavers on top. That article is about a paver patio, so treat the depth as a starting point and check it against your paver thickness and your soil.

Can I use play sand or beach sand under the pavers?

The sources we opened say to use concrete sand under pavers, and they warn against limestone screenings or stone dust. We did not open a source on play or beach sand, so we cannot say how it performs. Check with the paver maker.

Does a fire pit need a drainage hole?

The Polycor kit guide calls for a crushed stone drainage hole in the center of the excavation. It is a kit instruction, so it applies to that kit. If your pit is built from another design, ask the maker whether a drainage path is needed.

How much slope should the area have?

The Iowa State article gives a drop of 2 inches for every 8 feet, with the grade sloping away from any building. That keeps water moving away from the house and the pit.

Should I put adhesive on the pavers?

The Polycor guide says landscape adhesive can be used on the top row of its fire pit blocks for stability. The paver article does not mention adhesive, and it relies on the sand joints and the compacted base.

Bottom line

For fire pit types and sizes, see our guide to the best fire pits for patios and backyards, and for fuel-line parts, see our propane tank guide for gas fire pits.

Build the base first and keep it level. Use compacted gravel, a thin screeded sand layer, and sand in the joints, and build in a slope and a drainage path. Then follow the fire pit maker’s instructions for the ring and the fire.

Sources

Iowa State University Extension, Yard and Garden, “Installing Concrete Pavers, Part Two” (originally published June 30, 1995). https://yardandgarden.extension.iastate.edu/article/1995/6-30-1995/icppt.html. Opened 2026-10-30.
Outdoor Elements (Polycor), “Round Fire Pit Installation Guide,” PDF. https://www.polycor.com/wp-content/uploads/2023/03/Fire-Pit-Installation-Guide.pdf. Opened 2026-10-30.