Building a custom home in Los Angeles, on a lot you own or by knocking down the house that stands on it, runs through nine steps: feasibility, survey and soils, design, engineering and energy compliance, plan check, demolition, construction, inspections and the certificate of occupancy. Plan on more than a year from the first meeting to move-in. Construction alone averaged 10.5 months for contractor-built single-family houses in the U.S. in 2025, according to the Census Bureau, and in Los Angeles design, engineering and plan check all come before that clock starts. The decisions that move the budget most are made in the first few months.
Green Design and Build is a licensed residential general contractor (CSLB #1110975) based in Van Nuys, building across Los Angeles, Orange and Ventura counties and western Riverside and San Bernardino counties. We carry new homes and whole-home rebuilds from the first zoning check to the certificate of occupancy, hold a 4.7-star rating across 146 Yelp reviews and have completed more than 500 projects. Every dollar figure here comes from our published cost guides and is a budgeting range, not a quote. Zoning and code references are general information for the City of Los Angeles; we confirm them for your address.
Building on your lot vs. a knockdown-rebuild: what changes
The finished house can be identical. What differs is the first six months: a teardown adds a second permit, an asbestos process, a neighbor-notice period on older houses, and the loss of anything the old house was allowed to keep.
| Factor | Building on a vacant lot | Knockdown-rebuild |
|---|---|---|
| Extra permits before construction | None for demolition; utilities may need extending to the lot | LADBS demolition permit, a sewer cap permit, an asbestos survey and an air-district notification |
| Extra waiting time | None from demolition | At least 30 days of mailed and posted notice if the house is 45 years old or more, and at least 10 working days of air-district notice |
| What the ground can hide | Undocumented fill, no sewer in the street, unknown soils | An unmapped sewer lateral, an abandoned septic tank, uncompacted fill under the old slab |
| What you can lose | Nothing | Setbacks or floor area the old house had that current zoning would not allow new |
| Best when | You have the land and the budget for site work | The structure, layout or foundation no longer justifies keeping the house |
Most rebuilds we are asked about do not start out as rebuilds. On a whole-home rebuild in Woodland Hills, the finishes came off and very little of the original structure was worth keeping; a few walls stayed and everything else, from the foundations to the roof, was built new. That call is cheapest when it is made at the start, with the drawings and permits matching what will actually be built.
Step 1: Feasibility, or what the lot will let you build
Feasibility answers one question before anyone draws a floor plan: how large a house, and in what shape, will the city approve here? On a standard R1 lot in the City of Los Angeles outside a Hillside Area or the Coastal Zone, the maximum residential floor area is 45 percent of the lot area, counting the house and every accessory building together (LAMC §12.08 C.5). A 7,000 square foot lot supports roughly 3,150 square feet. The same section sets the yards:
- Front yard: 20 percent of the lot depth, capped at 20 feet, unless the developed lots on the block establish a different prevailing setback.
- Side yards: 5 feet for up to two stories; on lots narrower than 50 feet, 10 percent of the width, never less than 3 feet.
- Rear yard: 15 feet.
- Encroachment plane: an angled limit starting 20 feet above grade along the front and side setbacks, which shapes how a second floor can sit.
The city also has R1 variation zones with different massing rules, and RE, RS and RA lots have their own standards, so feasibility starts with the zoning of the specific parcel, not a rule of thumb.
Hillside lots and the Baseline Hillside Ordinance
On R1, R1H, RS, RE and RA lots in a mapped Hillside Area, the Baseline Hillside Ordinance replaces the flat-lot math. Maximum floor area comes from a slope-band table applied to a slope analysis survey approved by City Planning, with a guaranteed minimum of 800 square feet. Height is measured from hillside grade, the front yard follows the prevailing setback, and grading is capped at 1,000 cubic yards plus 10 percent of the lot area in cubic yards. Because the answer depends entirely on the survey, we do not quote a hillside percentage until the slope analysis exists. Hillside houses also bring retaining walls into the design; see our guide to retaining walls on sloped lots.
What else feasibility checks
- Historic Preservation Overlay Zones, historic monuments, the Coastal Zone and Specific Plans, each of which adds a review and some of which can block a demolition.
- Fire hazard mapping, which decides whether the wildfire construction rules described below apply.
- Sewer in the street, and the size of the existing water and electrical services.
- Protected trees, which need an Urban Forestry clearance before demolition.
- Access for equipment and concrete trucks.
Step 2: Survey and soils, before the first drawing
Two reports decide more of the budget than any finish. A boundary and topographic survey fixes the property lines the setbacks are measured from and the grades the height is measured from. A geotechnical (soils) report tells the structural engineer what the ground will carry and whether the house needs ordinary continuous footings, a thicker reinforced or post-tensioned slab, or drilled caissons and grade beams. Where the soil is expansive, with an expansion index above 20 under the California Building Code, the foundation has to be designed for it.
On a teardown the soils engineer also looks for what the old house left behind: uncompacted fill, a buried tank, a sewer lateral nobody mapped. Finding those on paper costs a report; finding them with an excavator costs a change order.
Step 3: Design, and the decisions that drive cost
Design is where most of a custom home’s cost is fixed. None of the choices below is wrong; each has a price.
| Decision | Lower-cost direction | Higher-cost direction | Why it matters |
|---|---|---|---|
| Foundation | Slab or continuous footings on a flat lot | Caissons, grade beams and retaining walls on a hillside | On a steep lot the site work can rival the framing |
| Shape | A simple footprint with walls that stack floor to floor | Many corners, cantilevers and walls that do not line up | Every jog adds framing, flashing, roofing and engineering |
| Spans | Rooms sized to ordinary lumber and engineered-wood spans | Long open spans that need steel beams or moment frames | Steel adds fabrication lead time and another trade on site |
| Glazing | Standard window and door sizes | Window walls and large multi-panel sliders | Large openings need more structure and energy-code trade-offs |
| Selections | Every finish chosen before the foundation is poured | Finishes chosen or changed during framing | Late changes cost both money and schedule |
Our cost to build a house in Los Angeles guide puts a new house at $300 to $600 per square foot all-in, covering design, engineering, permits and construction but not the land, so a 2,000 square foot house is roughly $600,000 to $1,200,000. Hillside sites and custom finishes go higher. These are budgeting ranges, not a quote, and our LADBS permit costs guide explains the fees inside them.
See the house before it is engineered: a 3D design model lets you walk the rooms and catch a wrong window while changing it is still cheap. In a design-build process, the people drawing the house price it as they draw, so the plan that reaches plan check is one the budget can build.
Step 4: Engineering, energy compliance and the 2026 codes
The permit set carries structural engineering, civil grading and drainage on sloped lots, and the Title 24 energy compliance documents. The 2025 California codes took effect on 1 January 2026 and shape a new house in four specific ways.
The 2025 Energy Code
Local building departments began enforcing the 2025 Energy Code on 1 January 2026. The California Energy Commission sums up the direction for homes plainly: heat pumps for both space heating and water heating. For a new single-family house:
- Heat-pump space heating is the baseline. The prescriptive path calls for heat-pump heating in every climate zone; any other system has to prove itself through the performance path.
- Solar PV is required, sized from the roof area with good solar access; very small or poorly exposed roofs can qualify for an exception.
- Battery-ready wiring is required when electrical service exceeds 125 amps, unless a battery is installed.
- Electric-ready circuits: a gas furnace, range or dryer needs a dedicated 240-volt circuit and reserved panel space beside it, and a future heat-pump water heater needs at least a 30-amp branch circuit.
Sprinklers, EV-ready garages and wildfire construction
- Fire sprinklers: the 2025 California Residential Code (R309.2) requires an automatic sprinkler system in one- and two-family dwellings.
- EV-ready garage: CALGreen 4.106.4.1 requires a new house with an attached private garage to have a raceway and panel capacity for a 40-amp, 208/240-volt charging circuit, or the circuit itself.
- Wildfire construction: a house in a designated wildland-urban interface area is built to the 2025 California Wildland-Urban Interface Code (Title 24, Part 7), which governs roofs, vents, siding, decks and glazing; our home hardening for wildfire guide explains the materials.
Step 5: LADBS plan check
A new house in the City of Los Angeles is permitted through Regular Plan Check, the LADBS process for large and complex projects. Plans can be submitted electronically through ePlanLA and are processed at the Metro, Van Nuys or West Los Angeles offices. LADBS says plans are assigned within a few days and reviewed and returned within weeks, depending on workload; paying 50 percent more in plan-check fees buys an expedited review. What really sets the calendar is everything around that review:
- Corrections. The plan checker returns a correction list, and the designer and engineer answer it and resubmit. A complete, coordinated first submittal is the biggest time-saver.
- Other departments. Depending on the lot, City Planning, the Fire Department, Sanitation, the Bureau of Engineering and the Department of Water and Power each clear the project.
- Hillside review. On a hillside lot, the soils and geology reports, slope analysis and grading plan are all reviewed and can each generate corrections.
A preliminary plan check meeting with an LADBS engineer can settle an unusual code question before submittal.
Step 6: Demolition, for a knockdown-rebuild
Taking down a house is its own permitted project, governed by LADBS Information Bulletin P/BC 2026-039 and South Coast AQMD’s asbestos rule:
- Asbestos survey and notice. AQMD Rule 1403 requires a survey by a Certified Asbestos Consultant before every demolition, and notification to the AQMD at least 10 working days before work starts, whether or not asbestos is found.
- Permit and pre-inspection. A licensed demolition (C-21) or general engineering (A) contractor applies with a dimensioned plot plan, and a building inspector visits before the permit issues.
- Notice for older houses. If the original permit was issued more than 45 years before the pre-inspection application, notice is mailed to abutting owners and occupants, the Council District office and the Neighborhood Council, and a “Notice of Demolition” placard is posted, at least 30 days before the permit can issue.
- Clearances and sewer cap. Historic, coastal and protected-tree clearances apply where relevant, and a sewer cap permit is required, with the cap inspected before it is covered.
Run these in parallel with plan check, but do not take the house down until you know the new one is approvable. Once it is gone, any setback or floor area it was allowed to keep goes with it.
Step 7: Construction, phase by phase
Each phase is inspected before the next one covers it:
- Site work and grading: erosion control, rough grading, utility trenches, and on hillside lots, shoring and retaining walls.
- Foundation: under-slab plumbing, then footings or slab formed, reinforced, inspected and poured.
- Framing and roof: walls, floors, shear walls and hold-downs, then sheathing, windows and roofing so the house is dried in.
- Rough trades: plumbing, electrical, HVAC and fire sprinklers, performed by licensed specialty contractors we schedule and supervise as your general contractor.
- Insulation and drywall: insulation is inspected before the walls close.
- Finishes: exterior cladding, cabinets, tile, flooring, fixtures, paint, appliances and the solar system.
- Site finishes: driveway, walks, drainage and any landscaping the approvals require.
The Census Bureau’s Survey of Construction gives the best national benchmark for this phase: in 2025, single-family houses built by a contractor on the owner’s land averaged 10.5 months from start to completion, against 6.1 months for houses built for sale and 12.8 months for owner-built houses. Custom homes take longer than spec homes because every plan is a first build, and 26 percent of contractor-built houses completed in 2025 took 13 months or more.
Step 8: Final inspection and the certificate of occupancy
Final inspection closes out every permit on the job: building, electrical, plumbing, mechanical, fire sprinkler and, where there was one, grading. LADBS is required to issue a certificate of occupancy for every new building; it is the document that says the house may be lived in. Keep it with the approved plans, permits and warranty paperwork.
How long does it take to build a house in Los Angeles?
On most lots, more than a year from the first meeting to move-in. The months before construction depend mostly on how quickly and how finally decisions are made; the months on site depend on size, foundation and changes.
| Phase | What sets the length | Published benchmark |
|---|---|---|
| Feasibility, survey and soils | Zoning, overlays, hillside slope analysis, access | Our site visit takes about two hours, with a written proposal within 48 hours |
| Design and engineering | Design rounds, consultant reports, speed of selections | Driven by your decisions; no standard figure exists |
| LADBS plan check | Completeness of the submittal, corrections, other departments | Assigned within a few days, returned within weeks; expedited review for 50% more in plan-check fees |
| Demolition (teardowns only) | Age of the house, asbestos, clearances | At least 30 days of notice for houses 45 years or older; at least 10 working days of AQMD notice |
| Construction | Size, foundation, site, change orders | 10.5 months on average for contractor-built single-family houses in the U.S. in 2025 (Census Bureau) |
| Final inspection and certificate of occupancy | Punch list and sign-offs on every permit | Follows the last inspection |
For scale, our second-story additions run nine to fourteen months from the first meeting to the final inspection, and a ground-up house runs longer, with most of the extra time in design, engineering and plan check rather than on site. The usual causes of delay:
- Redesign after engineering starts. A moved wall ripples through the structural drawings, energy calculations and plan-check set.
- An incomplete first submittal, which adds review cycles.
- Utility service. A new or upgraded electrical service can take months to schedule, so we file for it during plan check.
- Late selections of windows, cabinets and long-lead items.
- Demolishing too early, leaving an empty lot that still carries a mortgage and taxes while approvals catch up.
Keep and remodel, or knock down and rebuild?
This comes up on most 1940s to 1960s Los Angeles houses whose lot is worth more than the building. Our whole-home renovation cost guide puts a full gut to the studs at $250 to $400 per square foot and a gut with structural changes at $350 to $500 or more, against $300 to $600 all-in for building new. These are budgeting ranges, not a quote. Per square foot, new is the higher number; what separates them is what you get.
Rebuilding usually wins when the foundation and framing both need major work, when the layout you want cannot be reached without removing most of the walls, or when you want a larger or two-story house the zoning allows. If the foundation is the only real problem, foundation underpinning can sometimes save the house for far less.
Remodeling usually wins when the structure is sound and the plan mostly works (our whole-home renovation service covers that route), when the existing house sits closer to a property line or holds more floor area than current zoning would allow new, or when it is in a Historic Preservation Overlay Zone, where demolition may not be approved at all.
If your house was lost in the January 2025 fires, different rules apply; see our guide to rebuilding after the Palisades or Eaton fire.
Your team, your contract and your money
- Check the license before you sign; our guide on how to verify a contractor’s license in California walks through the CSLB lookup.
- Insist on a defined scope: drawings and engineering, the site work assumed and the soils report behind it, the foundation type, every trade, finishes by product or named allowance, permits and fees, and exclusions. Anything outside it goes through a written change order first.
- Tie payments to inspected milestones, not the calendar; see our guide to contractor payment schedules in California.
- Carry a contingency of 15 to 20 percent of the accepted bid on any teardown.
- Line up the money early; our financing options page explains the programs we offer.
- Plan the whole lot. If you may want a rental or family unit later, put an accessory dwelling unit (ADU) into the feasibility study now, because the yard it needs affects where the house sits.
Building a custom home FAQs
How long does it take to build a custom home in Los Angeles?
On most lots, more than a year from the first meeting to move-in. Construction alone averaged 10.5 months for contractor-built single-family houses in the U.S. in 2025 (Census Bureau), and in Los Angeles design, engineering and LADBS plan check come first. A teardown adds demolition steps, including at least 30 days of notice when the house is 45 years old or more.
What is the first step in building a custom home on my own lot?
A feasibility check, before any design: the zoning and floor area the lot allows, hillside, historic, coastal or fire-zone overlays, sewer and utilities, protected trees and access. Then a boundary and topographic survey and a soils report, so the house is designed for the ground it will sit on.
How big a house can I build on my lot in Los Angeles?
On a standard R1 lot outside a Hillside Area or the Coastal Zone, all buildings combined can reach 45 percent of the lot area under LAMC §12.08 C.5, about 3,150 square feet on a 7,000 square foot lot, within the front, side and rear yards. Hillside lots are sized by a slope analysis under the Baseline Hillside Ordinance instead.
Do I need a permit to tear down my house in Los Angeles?
Yes. LADBS issues a demolition permit after a pre-inspection and a sewer cap permit, and South Coast AQMD requires an asbestos survey and notice at least 10 working days before any demolition. If the house’s original permit is more than 45 years old, neighbors must be notified and a placard posted at least 30 days before the permit issues.
How much does it cost to build a custom home in Los Angeles?
Our published budgeting range is $300 to $600 per square foot all-in, covering design, engineering, permits and construction but not the land, or roughly $600,000 to $1,200,000 for 2,000 square feet. Hillside sites and custom finishes push it higher. It is a budgeting range, not a quote; the real number comes from a written proposal after a site visit.
Is it cheaper to remodel or knock down and rebuild?
Per square foot, remodeling is usually lower: $250 to $400 for a full gut and $350 to $500 or more with structural changes, against $300 to $600 all-in for new construction. Rebuilding makes sense when the foundation, framing and layout all need replacing; remodeling wins when the structure is sound or the old house holds setbacks or floor area new construction would lose.
Does a new house in California need solar panels and a heat pump?
Solar, yes, with limited exceptions for very small or poorly exposed roofs. Under the 2025 Energy Code, enforced from 1 January 2026, the prescriptive baseline for space heating is a heat pump in every climate zone, and any other system must meet the performance budget instead. Battery-ready and electric-ready wiring are also required.
When do I get a certificate of occupancy for a new house?
After the final inspection closes out every permit on the job: building, electrical, plumbing, mechanical and fire sprinkler. LADBS is required to issue a certificate of occupancy for every new building, and it confirms the house may be occupied.
Sources
Checked against the official sources below on 10 October 2026. Codes and fees change, and cities outside Los Angeles apply their own zoning, so confirm current rules for your address.
- Los Angeles Municipal Code §12.08, R1 One-Family Zone: yards and the 45 percent floor area limit.
- LADBS Baseline Hillside Ordinance correction sheet.
- LADBS Regular Plan Check: assignment, review times and expedited review.
- LADBS Information Bulletin P/BC 2026-039, Demolition of Buildings.
- South Coast AQMD Rule 1403 notification instructions.
- LADBS Information Bulletin P/BC 2023-109, Certificate of Occupancy.
- California Energy Commission, What’s New for 2025: Single-Family, and the 2025 Energy Code fact sheet.
- 2025 California Residential Code, Chapter 3 (R309.2) and 2025 CALGreen, Chapter 4 (4.106.4.1).
- U.S. Census Bureau, Survey of Construction: length of time.
Start with your address
Send us the address and a sentence about the house you want. We will check the zoning, overlays, sewer and soils questions, walk the lot with you, and tell you whether you are looking at a remodel, a rebuild or a new build, with a written, itemized proposal within 48 hours of the visit. We reply within one business day and answer the phone 8am to 6pm, every day. You can also read what our clients say.