A patio you can use on a hot afternoon, a firm path to the gate, stone instead of bark against the house. Shaun lays it out around your septic field first, so nothing has to be torn up later — and builds it to stay flat on decomposed granite.
CSLB #979389 · C-29 Licensed · Bonded $25,000 · Free on-site estimates
Outdoor paving by the numbers
In most of the county a patio goes wherever the view is. Here, on a lot without sewer, it goes where the septic system allows. The County’s 2024 onsite-wastewater rules forbid covering a new or replacement dispersal field with any impermeable surface — paving, slabs or plastic — and won’t let a field sit in an area paved or planned for paving. Leach lines keep 8 feet from structures, driveways and pools; the tank keeps 5 feet. If an old field fails, the County can make you remove patios and walks over the usable ground before it approves a repair.
The community plan pushes the same way for its own reasons. It asks for as little non-permeable paving as possible, for walls, screens and canopies to shade the paving that is built, and for gravel or ground cover instead of solid paving around houses where that works — this is, in the plan’s words, a “hot arid climatic zone”. Meanwhile state law wants the first 5 feet around the house kept ember-resistant. Pavers, stone and gravel, placed with a plan, satisfy all three.
Patios, walks, pool surrounds and the first five feet around the house. Material choices and base detail for each are on our pavers, patios and pool decks pages; here’s how they fit a septic lot in the hills.
Patios
Interlocking pavers on a compacted base with edge restraint, placed on the side of the house away from the dispersal field and its reserve area. Where the view is over the field, we put a small terrace at the edge and keep the field itself planted.
Fire
A band of pavers, flagstone or gravel against the walls in place of bark mulch and shrubs — the zone state law singles out. It also gives you a clean edge to sweep and a place for the hose.
Stone
Flagstone set dry in decomposed granite lets rain soak in, which the community plan favours, and suits Crest’s granite setting. Mortared on a slab where you want a tight, formal terrace instead.
Pool decks
Paver or stone decks and coping around new and existing pools. The pool itself must keep 8 feet from leach lines, so the deck layout follows the same septic map — and the pool barrier needs its own County permit.
Walks
Stepped paver or stone stairs down a slope, and packed decomposed-granite paths with stone edging — the surface the community plan prefers to concrete sidewalks.
Shade
Low stone or block seat walls on the west side of a patio, and footings for a shade structure, so the paving doesn’t bake — the plan asks for walls, screens and canopies to shade hard surfaces.
Decomposed granite compacts well and drains fast, which is good news under pavers. The trouble is what it does when water runs across it: it moves. So the base is dug out to firm ground, built back in compacted lifts of crushed aggregate, finished with bedding sand and locked with edge restraint, and the whole surface is graded to shed water away from the house and away from the septic field.
Over a tank lid or access riser we leave access, never a mortared cap. If any part of the paving carries vehicles within 5 feet of the tank, the County requires a traffic-rated tank or an engineered slab. And where pervious pavers form part of a fire-access drive, the County Fire Authority wants them rated for the weight of a fire engine.
Crest, Dehesa, Harbison Canyon and the County part of Granite Hills follow County of San Diego rules. A patio, walk or deck no more than 30 inches above the ground beside it, not over a basement and not part of an accessible route, is exempt from a building permit. Raised terraces, pool barriers and anything that moves enough earth for a grading permit are not.
The septic rules apply whether or not there’s a building permit. If you’re adding a pool, a patio cover or a big terrace near the system, the County Department of Environmental Health and Quality may need to see the layout. We plan the paving to stay out of the field and its reserve area so that question usually never comes up.
The three surfaces we lay most often up here, and how each sits with the County and the plan.
| Interlocking pavers | Flagstone, dry-laid | Gravel or DG with stone edge | |
|---|---|---|---|
| Best for | Patios, pool decks, drives | Terraces, paths, garden seating | Ember zone, side yards, paths |
| Water | Sheds to a drain or edge | Soaks in through the joints | Soaks in |
| Over a septic field? | No | No — it is still paving | Ask first; keep it shallow and loose |
| Fits the plan’s policies | Shaded and kept compact | Yes — permeable, natural material | Yes — named in COS 1.5.6 |
| National cost (installed) | $10–$25 per sq ft (patio) | $16–$30 per sq ft (patio) | Quoted per job |
Sources: County LAMP 2024; community plan policies COS 1.5.4–1.5.6; Fixr patio cost guide (national, 2022).
Tank, leach lines and reserve area located from the County record or on site, and marked before anything is drawn.
Patio, pool deck and paths placed outside the setbacks; the ember-resistant band drawn against the house.
Loose decomposed granite and organic soil out; rock broken where it sits high.
Crushed aggregate in compacted lifts, graded to shed water away from the house and the field.
Pavers or stone set, edge restraint fixed, joints filled — or flagstone dry-laid in DG.
Final check of falls and edges, care notes, and a written workmanship guarantee.
Planning one? Shaun will walk the site with you and tell you what it needs — free, no obligation.
Call (619) 581-2492National cost guides give a starting point. A Crest–Dehesa job moves with how far the materials travel up a steep drive and how much rock comes out of the base. These are national cost-guide figures, not our prices.
| Project (national guide) | Typical installed range |
|---|---|
| Paver patio | $10–$25 per sq ft |
| Flagstone patio | $16–$30 per sq ft |
| Paved driveway, overall | $8–$25 per sq ft |
| Concrete deck, 12 × 24 ft pool | $7,500 average |
Sources: Fixr patio (2022), paved driveway (Aug 2025) and pool deck (Jan 2025) cost guides, national. Our written proposal itemises base, rock removal and haul-off.
Lot size and the septic layout change the job more than the address does — but the address tells us what to expect.
The Crest–Dehesa page covers the ground, permits and neighbourhoods across every kind of job. The county-wide pages go deeper on the build itself.
Straight answers before you hire. Anything else — call, and Shaun answers it himself.
Call (619) 581-2492Not over a new or replacement field — the County’s 2024 septic rules forbid covering one with paving, slabs or plastic, and a field may not be placed where paving is planned. Even over an older field it’s a bad idea: if the field fails, the County can require paving over the usable area to come out before a repair is approved.
The County table keeps leach lines 8 feet from structures, driveways and swimming pools, and the septic tank 5 feet. A patio at grade isn’t listed on its own, but it can’t cover the field — so we keep it outside both.
Not for a patio, walk or deck no more than 30 inches above the adjacent ground, not over a basement and not part of an accessible route. Raised terraces, pool barriers and big grading jobs do need County permits.
Something that won’t burn: pavers, flagstone, concrete or gravel instead of bark mulch and shrubs. State law singles out that ember-resistant zone within 5 feet of the house as part of defensible space.
It can. The community plan calls this a hot, arid zone and asks for shade over hard surfaces. Lighter pavers or stone, a seat wall on the west side and a shade structure make a big difference on a summer afternoon.
Both work on a properly built base. Pavers flex with small movement and can be lifted for repairs; a slab is cheaper per foot but cracks show. See our concrete page for the area for driveways and slabs.
Yes — based at 2351 Eltinge Dr, Alpine, next door to Harbison Canyon. California C-29 masonry licence #979389, bonded and insured.
Call Shaun at (619) 581-2492 or send the form. He’ll find the septic system, show you where paving can go, and give you a written, itemised price.
