The custom home design process takes 3 to 6 months and moves through four phases: schematic design, design development, construction documents, and LADBS plan check.
Big-picture decisions. Floor plan layout, room sizes, overall style, site placement. You'll review 2-3 concept options. Decisions: number of stories, bedroom/bathroom count, garage size, outdoor living scope. Deliverable: preliminary floor plans and basic elevations.
Refining the approved concept. Interior layouts, material selections, fixture specifications, window and door placement. Kitchen and bathroom designs detailed. Structural engineer and MEP consultants join. Deliverable: detailed floor plans, sections, material boards.
LADBS-ready drawings. Full architectural plans, structural engineering, Title 24 energy calculations, MEP plans, landscape plan. Every detail specified for bidding and construction. This is the most technical phase — your architect coordinates with 3-5 engineering consultants.
Submit to LADBS for review. New construction gets thorough review: structural, fire/life safety, energy code, accessibility, zoning compliance. Corrections are common — typically 1-2 rounds. Express plan check available for ~40% surcharge.
In a design-build model (like NP Line Design), the builder is involved from Phase 1. This means: real-time budget feedback during design, no surprises at bidding, and construction-ready details that reduce change orders. Design-build saves 2-4 months and 5-15% vs separate architect + builder.
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NP Line Design (CSLB #1105249). April 2026.
“Custom home design in LA follows a longer process than most clients anticipate, and the LADBS plan check timeline is the primary driver. A sophisticated design team can produce construction documents in 4 to 6 months, but then another 6 to 12 months may pass waiting for plan check approval, corrections, and resubmittal — depending on project complexity, overlay zones, and department workload. I tell clients to budget 18 to 30 months from first architect meeting to construction start for a complex custom home, and 12 to 18 months for a relatively straightforward project on a standard lot.”
The highest-value early investment in a custom home design process in LA is a pre-application conference with LADBS ($200 to $400 fee). This meeting surfaces any project-specific requirements — particular soil reports, fire department sign-offs, or planning department reviews — before your architect invests 6 months in drawings. Projects that do not do this pre-application meeting routinely go through 2 to 3 major correction cycles that add 4 to 8 months to the plan check process.
1. Hiring an architect based on their residential design portfolio without verifying their experience navigating LA-specific code requirements — an architect who routinely works in San Diego or Orange County will have real learning curve costs in LADBS
2. Finalizing interior design selections (tiles, fixtures, hardware) before the framing and rough-in are complete, then discovering that actual wall and ceiling dimensions differ slightly from the drawings
3. Not building a design contingency into the owner's budget — design changes during plan check or during construction are almost universal, and they cost real money in consultant time and schedule impact
If an architect presents you with a custom home design that was not preceded by a geotechnical report and a verified LADBS zoning review for your specific lot, they are designing in the abstract. Structural systems, foundation types, and architectural proportions all depend on site-specific data that must precede design, not follow it.
The LA custom home process runs: (1) Lot feasibility and programming (1 to 2 months), (2) Schematic design (2 to 3 months), (3) Design development and structural engineering (2 to 3 months), (4) Construction documents (2 to 3 months), (5) LADBS submittal and plan check (6 to 12 months), (6) Permit issuance and contractor bidding (1 to 2 months), (7) Construction (12 to 24 months depending on size and complexity).
Architectural fees for a custom home in LA typically run 8 to 15 percent of total construction cost. On a $2,000,000 construction budget, that is $160,000 to $300,000 in design fees. Add structural engineering ($30,000 to $80,000), civil engineering ($20,000 to $50,000), geotechnical ($8,000 to $20,000), and energy consulting ($8,000 to $20,000). Total pre-construction design and engineering costs often reach $250,000 to $500,000.
Design-build combines architecture and construction under one contract with a single entity. The advantage in LA is faster schedule (design and permitting can overlap with preconstruction bidding) and clearer accountability (no disputes between architect and GC). The disadvantage is less independent design oversight — the same company doing design and construction has financial incentive to simplify both. Design-build works well for clients who prioritize schedule and budget certainty over maximum design flexibility.
Construction of a custom home in LA after permit issuance runs 12 to 24 months for 2,500 to 5,000 square feet. Larger homes (5,000 to 10,000 square feet) typically run 20 to 36 months. High-end custom homes with complex structural systems, imported materials, or highly detailed finishes can run 3 to 5 years. LADBS inspection scheduling adds time that is often not accounted for in contractor schedules.