ADU Drafting Services: What They Cost and How to Choose

ADU Drafting Services: What They Cost and How to Choose

Every legal ADU starts as a set of drawings before it's a single stud in the ground. Search "drafting services near me" and you'll get a mix of independent drafters, building designers, architects, and design-build contractors — all offering to turn your idea into plans a city will approve. They are not interchangeable, and picking the wrong one wastes money and months.

The 30-second answer

An ADU drafting service produces the construction and permit drawings — site plan, floor plan, elevations, sometimes structural — that your city's building department reviews before issuing a permit. In California, most standard ADUs don't legally require a licensed architect; a qualified building designer or drafter working with a licensed structural engineer is enough for the majority of projects. Expect to pay roughly $3,000–$15,000 for drafting alone, or have it bundled into a design-build builder's fixed price. For a deeper look at when you actually need a licensed architect versus a drafter, see our design-build vs. architect guide for Los Angeles.

What "ADU drafting services" actually covers

A drafter takes your rough idea — a detached unit in the backyard, a garage conversion, an attached addition — and produces the drawing set a plan checker needs to sign off on:

• Site plan showing lot lines, setbacks, existing structures, and where the new ADU sits
• Floor plan with room dimensions, door and window placement, and square footage
• Elevations showing exterior height, roofline, and materials
• Structural details (often stamped by a separate licensed engineer, not the drafter)
• Title 24 energy compliance documents, required on every California ADU

What a drafter typically does not do: pull the permit for you, manage the construction crew, or carry a contractor's license to build what's on the page. That's the split worth understanding before you hire anyone.

Drafter vs. architect vs. design-build builder

These three paths solve the same problem — permit-ready plans — at different price points and levels of hand-holding.

Independent drafter or building designer. The cheapest, fastest path for a straightforward detached or attached ADU on a standard lot. You bring the layout ideas; they produce compliant drawings. You're still responsible for finding a contractor separately.

Licensed architect. Worth the added cost on a tricky lot — steep slope, unusual setbacks, a design that needs to match a historic or architecturally distinct main house — or if you want a genuinely custom look rather than a standard layout. Our design-build vs. architect guide for Los Angeles breaks down when that added expense actually pays off and how to vet one.

Design-build ADU builder. Many builders in our directory fold drafting into the project instead of billing it separately. South Land Remodeling in Sherman Oaks lists architectural design and planning alongside pre-approved plans as part of its service; Golden ADU in Los Angeles and NEO Builders ADU in Studio City both bundle ADU design work with construction. The advantage: one point of accountability from drawings to move-in, and the drafting cost is baked into a single fixed-price quote instead of a separate line item you have to shop for.

If you'd rather not vet a drafter and a builder separately, browse vetted ADU builders in Los Angeles that already handle both.

What drafting actually costs

Pricing depends on scope, ADU type, and whether it's bundled:

These figures cover the drawings only — not the permit fees the city charges separately, and not construction. For the full build cost picture, see our Los Angeles ADU cost breakdown, which runs roughly $200,000–$450,000 all-in for a fully custom detached unit depending on size and finishes.

Stock plans vs. fully custom drafting

Not every ADU needs an original design from scratch, and skipping that step is often the fastest way to cut both cost and timeline.

Pre-approved or standard plans. Several California jurisdictions, including the City of Los Angeles, offer a Standard Plan Program: a library of pre-vetted ADU designs that skip most of plan check because the city has already approved the underlying design. If your lot is flat and unremarkable, this is usually the cheapest and fastest way to permit-ready drawings.

Modified stock plans. A drafter adjusts a standard design to fit your lot's specific dimensions and setbacks — less than a full custom design, more flexible than an off-the-shelf plan.

Fully custom drafting. Built from your specific goals: matching the main house's architecture, maximizing an oddly shaped lot, or fitting a design around mature trees or slope. This is where the cost climbs and where a licensed architect's judgment tends to earn its fee.

Do you actually need a licensed architect?

This is the question that trips up most homeowners searching for drafting help. The short answer: usually no. Most standard California ADUs don't legally require an architect's stamp — a qualified building designer or drafter, paired with a licensed structural engineer for the structural calculations, satisfies most jurisdictions' plan check requirements. An architect becomes worth it when the project is genuinely complex: a sloped or irregular lot, a design meant to visually match a distinctive main house, or a multi-story attached addition where structural and design decisions are tightly linked. Our design-build vs. architect guide for Los Angeles walks through exactly which situations tip the scale toward hiring one, plus how to evaluate architects specifically.

How to choose a drafting service (or a builder who bundles it)

Whether you hire a standalone drafter or a design-build builder, the vetting checklist is the same:

1. Ask who stamps the structural drawings. A drafter isn't a structural engineer — confirm who provides the stamped calculations your city requires, and that it's a separately licensed professional.
2. Get a fixed price for the full drawing set, not a per-revision hourly rate that can balloon once you start making changes.
3. Ask how many ADU sets they've drawn for your specific city. Plan-check requirements vary by jurisdiction, and local experience shortens the review cycle.
4. If bundling with a builder, confirm the CSLB license. How to vet an ADU builder in LA covers verifying an active Class B license, bond, and insurance before you sign anything.
5. Never hand over more than the legal deposit. California caps a contractor's down payment at $1,000 or 10% of the contract, whichever is less — the same cap applies whether drafting is billed separately or bundled into the build contract.

What happens after the drawings are done

Finished plans go to the city for plan check, which is capped at 60 days for a compliant, complete application under California's streamlined ADU law — though real-world review often runs shorter once the application is complete and correctly submitted. Once permits are issued, your drafter's job is typically done; a design-build builder instead rolls straight into construction using the same team, which is the main scheduling advantage of not splitting drafting and building across two separate hires. For the full permit process, see how to get an ADU permit in Los Angeles.

Get matched with a vetted option

If you already know you want an architect's level of design work, start with our design-build vs. architect guide for Los Angeles to understand the cost and process before you call anyone. If a straightforward drafted set paired with a licensed builder is more your speed, browse vetted, CSLB-licensed ADU builders in Los Angeles — many handle design and drafting in-house, so you're not managing two separate hires and two separate invoices.