Fullerton, California

Your Fullerton architect is your builder.

Based in Fullerton. Remodels, room additions, and ADUs — designed, taken through City permits, and built under one contract by a licensed architect who is also a licensed general contractor.

AS Design Build is based in Fullerton. We design, permit, and build home remodels, room additions, and ADUs across the city — from Sunny Hills and Raymond Hills to Golden Hill, East Fullerton, and the historic neighborhoods near downtown — and in nearby Brea, Placentia, Yorba Linda, La Habra, and Buena Park.

What we do in Fullerton

Building in Fullerton: what's different

Historic districts and preservation zones

Fullerton protects many of its older neighborhoods. Residential Preservation Zones are regulated under Fullerton Municipal Code Chapter 15.48, with City design guidelines for additions and exterior changes. The City's website also lists additional proposed preservation zones under review in 2026, including Lower Golden Hill, Oceanview, and Skyline Park. If you're in or near one of these areas, check before you design.

Older housing stock

A large share of Fullerton's homes were built before 1970. They often have generous lots and good bones, along with outdated electrical, plumbing, and foundations — and sometimes past work done without permits. We account for these in design so they don't surprise you during construction. Most of these homes were also built before 1978; AS Design Build is an EPA Lead-Safe Certified Firm.

A city of established single-family neighborhoods

Fullerton has roughly 29,000 single-family homes (Fullerton Observer, 2020). Most homeowner projects here are remodels, additions, and ADUs on existing lots — the work we do every day.

Zoning lookup

Parcel zoning, lot size, and zoning maps are available through the City of Fullerton zoning page. The City's Planning Division can be reached at (714) 738-6559. We review zoning for your property in the first consultation.

Fullerton project questions

Not always. California Business and Professions Code Section 5537 allows anyone to prepare plans for a wood-frame single-family home of up to two stories plus basement. But any portion that departs from conventional wood-frame construction must be designed by a licensed architect or engineer, and the City still needs permit drawings that pass plan check, including structural and Title 24 energy compliance. Hiring an architect who is also your contractor means the person who draws the plans is responsible for building them.
Fullerton has designated historic districts, and several are Residential Preservation Zones under Fullerton Municipal Code Chapter 15.48. In those zones the City's Design Guidelines for Residential Preservation Zones apply on top of normal zoning — additions and exterior changes are expected to fit the neighborhood's original architecture in scale, materials, and rooflines. Minor work that follows the guidelines can typically be approved at staff level; major additions and new dwellings go through a more formal design review. We confirm your parcel's status in the first consultation.
On most single-family lots, yes. California law requires cities to allow ADUs on most single-family lots, and Fullerton applies its own standards within that framework. What fits depends on lot size and shape, setbacks, existing structures, and utility capacity. We start with a feasibility review of your parcel before any design fee is committed.
Many of Fullerton's 1920s–1960s homes have solid bones and a lot-size advantage that newer tracts lack, but they often hide outdated systems or past unpermitted changes. We walk the house and give you a rough comparison of remodel-and-add versus larger reconstruction before you commit.
Fullerton has 16 designated historic residential districts, and as of 2021, ten of them had been designated Residential Preservation Zones, where the City's design guidelines apply to exterior changes. The City's website also lists additional proposed preservation zones under review, including Lower Golden Hill, Oceanview, and Skyline Park.
Yes, through the Mills Act. Owners of properties in Fullerton's Historic Districts, and of National Register, Local Landmark, and Significant Properties, may apply to the City's Mills Act program, which offers property tax reductions in exchange for rehabilitating and maintaining the property.
Fullerton's local ADU standards are in Fullerton Municipal Code Chapter 15.17, adopted to implement state ADU law, which has changed several times since. The City's Planning Division can be reached at (714) 738-6559. See our ADU page for the state rules on size, height, setbacks, and fees.
Yes. When a permit for alterations, repairs, or additions valued over $1,000 is issued, the California Residential Code requires smoke and carbon monoxide alarms in the existing home, and the City of Fullerton requires an owner certification form confirming they are installed before the permit is finaled.
Yes. Aaron works in English and Korean — 한국어로 상담 가능합니다 — from the first site visit through design, permits, and construction.
AS

Written by Aaron Song — licensed architect and general contractor

CA Architect License #C-42133 · CSLB #1152969 (B - General Building Contractor) · EPA Lead-Safe Certified Firm · Master of Architecture, Harvard
Last updated October 2026. Code references are to California law as of this date; your City's review of your specific project governs.

Planning a project in Fullerton? Start with a site visit.

A free consultation at your house covers what's feasible, a rough budget range, and how the City process will go. English or Korean.

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