How do I build a fire pit with pavers?

A paver fire pit is usually a ring of heavy segmental wall blocks set on a compacted gravel base, with a steel insert or a firebrick lining inside to take the heat and flat pavers or flagstone around it as the patio. With a kit, the stacking takes an afternoon. Most of the work, and most of what decides whether the pit stays level and legal, is choosing the spot and building the base. This guide covers a wood-burning pit only.

Pick the spot first

Distance is the decision that matters most, and it is set locally. In Suffolk, a recreational fire must be more than 25 feet from any structure.^[3] Fairfax County is less clear-cut for a built-in pit. There, recreational fires may not be held within 25 feet of a structure or combustible material, but its definition of a recreational fire leaves out fuel contained in an outdoor fireplace or portable outdoor fireplace.^[1] Its rule for portable outdoor fireplaces, which it says includes fire pits, is 15 feet from a structure or combustible material, with an exception for one- and two-family dwellings.^[2] For a block pit in Fairfax, ask the fire marshal which rule applies before you dig.

The U.S. Fire Administration's general advice is to keep fire pits at least 10 feet from your home and anything that can burn,^[4] but where your county or city sets a larger distance, that is the one you must meet. Are backyard fire pits allowed in Virginia covers the rules in more detail.

Measure from the inside edge of the pit to the house, deck, fence, shed and woodpile, and look up for overhanging branches. A level spot saves work; a sloped one may need a retaining wall, which is a different job.

Size is local too. Suffolk limits a recreational fire to no more than 3 feet in diameter and 2 feet high,^[3] and Fairfax County sets a fuel area no more than 3 feet across and 2 feet high for a recreational fire,^[1] so an inside diameter of about 3 feet is a sensible ceiling for a backyard pit.

Call 811 before you dig

A fire pit pad is shallow, but it is still digging. In Virginia, contact Virginia 811 at least 3 working days before you dig,^[5] and wait for the marks. The service is free, and you need a new ticket each time you dig.^[5] State law sets a two-foot tolerance zone on either side of the marks,^[5] where digging is limited to methods such as hand tools.

Choose the materials

The ring. Use wall blocks or a fire pit kit made for the purpose. Their weight and interlocking lips keep the ring stable; thin patio pavers stood on edge usually are not.

The liner. Concrete block is not firebrick. Unilock notes that too much heat can break concrete units down over time unless the pit is designed for high temperatures, and recommends lining the fire pit with a metal liner or fire-rated brick.^[7] Its kits come with a metal insert meant to hold the shape and structure of the outer walls.^[7] If you prefer brick, Rutland's fire bricks, for example, can be used to line a fire pit, and the buff bricks are rated up to 2700°F.^[9]

The base. Use crushed stone sold as paver base, not round pea gravel, which does not lock together. Unilock's installation guide gives 4 to 6 inches of base for pedestrian walkways and says clay bases generally need to be dug deeper.^[6] The same base works under the ring and the patio around it. A plate compactor settles only about 4 inches at a time, so Unilock has you build the base up in layers of 3 to 4 inches.^[6]

The floor. Quikrete's poured fire pit plan finishes with a layer of lava rock as a thermally resistant surface to start fires on.^[8] The same works inside a block ring.

Building it

The steps above cover the order. A few points make the difference:

• Get the first course right. Every error in the bottom ring shows up twice as large at the top. Check each block with a short level both ways, and tap high blocks down with a rubber mallet rather than adding gravel under one corner.
• Stagger the joints. Each block should bridge the joint below it, as in a brick wall. Kits are usually designed so this happens on its own.
• Cut with care. If you have to cut a block, use a splitter or a masonry saw with a water feed to hold the dust down. Wear eye and hearing protection and a respirator.
• Let mortar and concrete cure. Rutland's Dry Mix 211 refractory mortar needs to air dry for at least 24 hours before heat is applied.^[10] Poured concrete takes far longer: Quikrete's plan says to let the concrete cure for 30 days before the first fire.^[8]

For the patio around the pit, how to lay a paver patio covers the base, edging and joint sand in detail.

Before the first fire

Keep extinguishing gear beside the pit. Fairfax County requires a portable fire extinguisher with at least a 4-A rating, or other equipment such as dirt, sand, a water barrel or a garden hose,^[1][2] ready to use. The U.S. Fire Administration also advises that you put a metal screen over a wood fire to keep sparks from drifting out.^[4]

The screen matters in spring. From February 15 to April 30, Virginia's 4 PM Burning Law bans open-air burning before 4 p.m. if the fire is within 300 feet of the woods or dry grass that could carry fire to the woods.^[11] The Virginia Department of Forestry says a fire completely contained within a ring of rocks, cinderblocks or a metal ring and covered by a 1/4-inch or smaller metal screen may be acceptable, but it must still be attended and flammable material should be cleared from a 20-foot area around it.^[11] Some localities are stricter: in Suffolk, during this period "there is no burning of any type permitted before 4 p.m."^[3] Burn dry, seasoned wood; why a fire pit smokes so much explains why, and how to keep a fire pit from cracking covers looking after the blocks.

Stop and call a pro if

• You want a gas fire pit or a gas line to it. Running natural gas or propane and connecting a burner is licensed work: Virginia's Board for Contractors certifies gas fitters as a regulated trade.^[12]
• The yard slopes enough that the pit or patio needs a retaining wall or steps to sit level.
• The only spot that fits is within your locality's distance of the house, a deck or a fence. Moving the pit is cheaper than a fire.
• You hit or damage a utility line while digging. Virginia 811's advice is to stop digging immediately, step away from the area and call 911 if the damage lets flammable, toxic or corrosive gas or liquid escape, or if there is any other danger.^[5] After that, notify the affected utility, then report it to Virginia 811.^[5]
• The utility marks run through the spot or you find an unmarked line, pipe or cable while digging.
• You want a built-in fireplace, chimney or outdoor kitchen rather than an open pit. Those need design, and often permits.

Getting it built

What a fire pit costs in Virginia explains what goes into a quote if you would rather hire it out. Browse fire pit and fire feature businesses, concrete and hardscaping businesses in Blacksburg, or more concrete and hardscaping answers.

Describe your fire pit once and licensed local businesses quote it.