Fire pit construction
The part of the garden you use all winter
Most Bay Area evenings are cool once the sun drops, even in summer. That is why a fire pit gets more use here than almost anything else we build. It turns a patio from somewhere you eat dinner into somewhere people sit for two hours after dinner, and it does it for nine or ten months of the year.
The mistake we get called out to repair is a pit that was added later. A ring of block set on top of a finished patio has a couple of hundred pounds bearing on a surface that was built for foot traffic, so the pavers under it dish, the joints open, and the pit itself starts to sit crooked. Once that happens the only real fix is to lift it and build the base properly.
So we do it the other way around. The pit gets designed with the patio itself, and the base under the whole seating area, the pit and the seat wall is built at the same time and to the same standard.
Why does the base under a fire pit matter so much?
Weight and concentration. A block pit with a stone face and a cap is heavy, it never moves, and it sits on the same few square feet forever. A patio base built for people and furniture will slowly give under that, and because the pit is a hard object surrounded by flexible paving, the settlement always shows as a dished ring around it. It is the first thing we design for in any structure we build on a paved surface.
We deal with it before anything is visible. Under the pit and the seat wall the aggregate goes deeper and gets compacted in lifts, the same way we build under a wall rather than under a walking surface. The paving then runs up to the structure and gets cut in cleanly against it. It is the same base thinking behind every hardscape job we plan, and it is the reason ours are still level years later.
How big should the pit and the seating circle be?
Smaller than most people first draw it, and further away than they expect. A pit that is too wide pushes everybody back out of the heat, and a seating circle drawn too tight is uncomfortable once there is a real fire going. We usually mark both out on the ground with paint and have you stand in it before a single block is laid.
A seat wall wrapped part way around is what makes the area work. Around eighteen inches high sits like a bench, and a cap deep enough to actually sit on comfortably, rather than perch on, is what separates a seat wall from a garden edge. Leaving the circle open on one or two sides keeps it from feeling like a pen. A curved seat wall is the same construction as any other wall we build, just freestanding.
Get a free estimate on your fire pit
Built into the patio base with a seat wall around it. Family owned, with a 20 year warranty on every installation.
Call (650) 705-0628Gas or wood, and what changes underneath?
Gas is decided before anything is paved, because the line has to be sleeved and run under the patio while the base is open. Retrofitting one afterward means cutting the finished surface. If there is any chance of a built in grill going in later, we sleeve for that at the same time and cap it off until you want it.
Wood burning is simpler to build and better for actual flame. The inside of the pit gets a fire brick or steel liner so the heat never bears directly on the block, and vent holes at the base feed air to the fire and let any water out. Either way we build the pit level with the cap sitting flat, which is what stops it looking homemade.
We lay Belgard units as a Master Craftsman, and they make kits for both, so the finish matches the paving around it either way.
Why choose Exterior Designs for your fire pit?
Because we build the patio, the seat wall and the pit as one job, with one base, one set of levels and our own crews. That is the difference between a fire pit that looks like it was always meant to be there and one that looks like it was added on a weekend.
We are an ICPI Certified Paver Installer and a Belgard Master Craftsman, family owned and operated, working only in interlocking pavers and natural stone. Every installation carries a 20 year warranty and estimates are free. If you want a fire pit in an existing patio or a whole new seating area from scratch, set up a free on site visit and Todd will lay it out with you in the garden.
Ask a paver installer
Straight answers about paver installation on the Peninsula
Can a fire pit be added to a patio I already have?
Yes, and it is worth doing properly. We lift the pavers in that area, build a deeper compacted base for the pit and seat wall, build the structure, then reset the paving cut in around it. Setting a heavy pit on existing paving sinks it.
How far does a fire pit need to be from the house?
Well clear of the house, the fence, the eaves and anything overhanging like a tree canopy or a patio cover. The exact clearance depends on local rules and on gas versus wood, so we check the requirements for your address first.
Is gas or wood better?
Gas is easier to live with: instant, no smoke, no ash and nothing to clean out. Wood gives you a real fire and costs less to build. Decide early either way, because a gas line has to be sleeved while the base is open.
How high should a seat wall around a fire pit be?
Around eighteen inches reads as a bench and sits comfortably for most people. Just as important is a cap deep enough to sit on properly, and enough distance back from the fire that you are warm rather than roasting. We mark it out first.
Will the heat damage the pavers or the block?
Not when the pit is built for it. The inside gets a fire brick or steel liner so flame never bears on the structural block, and vent openings at the base keep air moving. The surrounding paving only ever sees warmth.
Do you build fire pits outside San Carlos?
Yes. We build across the Peninsula, including Atherton, Redwood City, San Mateo, Burlingame, Hillsborough, Belmont and Menlo Park, usually as part of a patio or a wider back garden project. The on site estimate is free either way.