Accessory dwelling units
ADU (accessory dwelling unit) Builder
People looking for ADU builders, granny flats, or a backyard apartment usually want the same thing: a second home with its own kitchen, bath, and door. Wolf employees review the property, prepare the permits, build your modular ADU, and handle site work, delivery, and installation in Washington and Oregon, with third-party specialists when needed.
Where Wolf works
In Washington and Oregon, Wolf employees handle your project from property review and permits through construction, site work, delivery, and installation. Some projects require third-party services, such as surveys or septic design and installation, depending on the property and jurisdiction. Beyond Washington and Oregon, local contractors complete site work and utility connections.
Who it’s for
Who an ADU can work for
Homeowners adding a second dwelling
You want a complete little house with its own kitchen, bath, and door, without remodeling the primary home. That is a detached ADU, also called a backyard cottage, backyard apartment, or granny flat.
Families keeping someone close
A parent, adult child, or caregiver needs privacy and a legal dwelling, so the unit has to be permitted as housing rather than as a shop or RV.
Owners planning long-term rental income
Washington no longer requires owner-occupancy for ADUs inside urban growth areas. Your city or county may still add local rules, so we check the parcel first.
What Wolf builds
What Wolf builds
Wolf Industries is a prefab modular ADU builder at 607 SE Eaton Blvd in Battle Ground, Washington, so if you are looking for ADU builders near you in southwest Washington, our factory is local. Homes are inspected to the same IRC/IBC (International Residential Code / International Building Code) residential codes as site-built houses. They are not HUD (the federal standard for manufactured homes) manufactured homes or trailers. We have delivered more than 650 homes, with modular homes, ADUs, and tiny homes in our range. We offer turn-key service in Washington and Oregon. Idaho projects are special-plan only, and California projects are quoted one at a time.
Wolf employees from start to finish
Wolf employees handle evaluation, design, permitting, factory production, site work, delivery, and installation, with third-party specialists when the site or jurisdiction requires them.
Permit work in writing
We assemble the packet and file with your jurisdiction. If a permittable ADU is not possible on the property, the signed permitting agreement defines the eligible refund and exclusions.
Studio-to-family footprints
Published models run 307 to 1,232 sq ft, with one-, two-, and three-bedroom layouts. Tell us who will live there and what space they need. The property review comes before a recommendation.
The whole job, start to finish
Beyond floor plans and finishes, an accessory dwelling unit builder has to handle local ADU rules, permit timelines, utility connections, delivery access, the foundation, setbacks, and parking. In Washington and Oregon, Wolf employees handle the project through each stage, with services such as surveys or septic work brought in when needed.
Built around how you will use it
What would make daily life easier for the person living here? We can discuss storage, privacy, durable finishes, wider doorways, grab bars, low-step showers, or a ramp where needed. Ask about the features that matter to you; availability and scope need to be confirmed.
The property before the floor plan
The most common mistake is falling for a floor plan before anyone has checked the lot. We confirm placement, access, utilities, and the permit path first.
Process
How an ADU project works
- 1
Property evaluation
We start with the address and check jurisdiction, setbacks, lot coverage, delivery access, and utilities before we lock a floor plan.
- 2
Design and proposal
We match a pre-engineered model and finishes to the lot and give you one proposal that separates the home line from site work.
- 3
Permitting and factory
Site permitting and factory production can move in parallel. Washington L&I (or Oregon BCD) inspects the structure; your city or county inspects the pad and hookups.
- 4
Delivery and keys
Our field crew sets the home on a permanent foundation, connects utilities, and walks you through warranty and the Owner Portal.
Models
ADU layouts to explore
Each model page shows the starting price for the home itself. The complete project price depends on trench length, the foundation, and local fees, which we review during the property evaluation.
Notice the rooms and details you would use. These are layouts to explore; we need to review your property before recommending one.
Model B — 307 sq ft
City of Portland (only)A compact one-bedroom for City of Portland projects only; property review still required.
Model K — 432 sq ft
A one-bedroom layout to compare after we understand the property and your plans.
Model E / F — 616 sq ft
Two bedrooms when family or rental use needs a second room.
Questions
Frequently asked questions
What does an accessory dwelling unit builder do?
Is Wolf a detached ADU builder or a remodeler?
Do you handle permits?
Where do you build ADUs?
How is this different from a manufactured home?
What’s the difference between an ADU, a tiny home, and a modular home?
Is a granny flat or backyard apartment the same as an ADU?
How much does a Wolf ADU cost?
Can I use an ADU as a rental?
What should I look for in an accessory dwelling unit builder?
Keep reading
Related Wolf pages
What is an ADU?
Plain-English glossary: ADU, DADU (detached accessory dwelling unit), granny flat, backyard cottage.
Granny flat builder
Same dwelling when the household still says granny flat.
Mother-in-law suite builder
Family housing for a parent, permitted as an ADU.
ADU cost in Washington
Washington ranges, site-work caveats, Battle Ground and Vancouver.
Prefab vs stick-built
Factory modular vs on-site stick vs HUD manufactured.
See whether your lot can take an ADU
Send the address and how you would use the unit. We will check jurisdiction, access, utilities, and model fit, then give you a clear next step. The evaluation is free.
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