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AIM Builders / ADU Construction

ADU Construction
More room for what’s next.

Accessory dwelling units designed and built for your property, from a garage conversion to a detached unit.

ADU Construction in Redmond, Bellevue and the Eastside.

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Planning sketchStart with a plan

Make room for what comes next.

  • Detached, attached, or a garage conversion?
  • What's the intended use: rental, family, or a home office/studio?
Find your starting point

How much would you like to change?

These are project types, not an assumed order of price. Site work and existing conditions can change the comparison.

01

Garage conversion

Assess the structure, moisture conditions and work needed to create living space.

02

Attached ADU

Plan the connection to the existing house alongside access, privacy and utilities.

03

Detached ADU

A separate building with site preparation, construction access and utility connections.

An ADU is a small house with all the systems of a full one: foundation or conversion work, framing, plumbing, electrical, heating, a kitchen and a bathroom, plus its own permits and inspections. Whether it is a detached unit, an attached addition or a garage conversion, the build quality has to match the main home, because it becomes part of your property's value and daily life.

The honest starting point is your lot, not a floor plan. Size limits, setbacks, parking and utility connection rules are set city by city across the Eastside and Puget Sound, and they can differ lot by lot. We research what applies to your address, walk the property to check access and where sewer, water and power run, and only then talk about design and budget.

Once the site picture is clear, the process runs like our other work: a written, itemized estimate and schedule before construction, one point of contact through permits, inspections and the build, and a final walkthrough of the finished unit. We do not quote feasibility or approval timelines before seeing the property, because guessing at either one helps nobody.

A closer look / Planning your space

Start with the whole property.

Detached, attached, or a garage conversion?

An illustration to start the conversation. Your layout and specifications follow a walkthrough of your own space.

Existing homePossible ADUAccessUtilities to review
ADU site-plan illustration. Not to scale. Layout, materials and requirements depend on your project.
Layout, materials and the details

Three ways to add living space.

01

Detached ADU

A separate building provides physical separation from the main house. Planning starts with its location on the property, construction access and connections to utilities. Site work and the distance to existing services are important scope questions.

02

Attached ADU

An attached unit connects to the existing home. Review how the addition or conversion meets the current building, where the entrance will be and how shared systems and privacy will work. Existing construction affects design options.

03

Garage conversion

Converting a garage starts with assessing the structure and whether its floor, walls and roof are suitable for living space. Review moisture conditions, openings, insulation and utility routes before assuming the conversion is simpler than a new building.

04

Design, utilities and permitting

Coordinate the unit layout with access, water, sewer and electrical planning. Identify the required design information and applications with the permitting authority for the property. Confirm current requirements for that address and scope before finalizing the plan.

Your written scope

What goes into the work.

A site visit to confirm access, utilities, and local requirements before we finalize any design or price. We do not promise approval timelines, since that depends on your specific city's process.

  • Detached and attached ADUs
  • Garage conversions
  • Permitting and code compliance
  • Kitchenette and bathroom builds
  • Site-specific utility and access planning

The items included in your project are defined in your written estimate.

Plan the investment

What changes the total.

  • Detached new construction vs. converting an existing garage
  • Utility hookups: how far the unit sits from existing sewer, water, and electrical
  • Local permitting requirements, which vary by city and by lot
  • Kitchen and bathroom scope inside the unit
Compare scopes in the Pricing Guide
Before construction

Feasibility before a finished design

Start with the address, available property records and intended use. Review the applicable authority, site constraints, utility locations and access for equipment. A useful concept depends on those findings; it does not establish permit approval.

Questions, answered

Plan with a little more clarity.

How big can my ADU be?

Size limits are set locally and vary by city and lot, so we confirm this for your specific property rather than quoting a general number.

How long does permitting take?

Permitting timelines are set by the local jurisdiction and can vary. We'll tell you what applies to your project once we know your city and scope, not before.

Will an ADU increase my property value or work as a rental?

That depends on your local market and situation, which we're not positioned to advise on. We build to the plan you and your own research or advisor land on.

Does an ADU always need a permit?

Yes. A new dwelling unit, detached, attached or a garage conversion, requires building permits and inspections, and utility connections can involve separate reviews. Requirements differ by city across King and Snohomish County, which is why we research your address before finalizing any design.

How long does it take to build an ADU?

A typical ADU build runs in the range of a few months of on-site work once permits are in hand, scope dependent. Permit review time is set by your city and is outside our control, so we do not promise approval dates. We give you a construction schedule with the written estimate.

Can we live at home while the ADU is built?

Almost always. Most of the work happens outside the main house, and we agree on access, working hours and staging before anything starts. Utility tie-ins are planned to keep interruptions short and scheduled, not surprises.

Also see

Keep planning.

Related services, planning tools and the areas we build in.

Complete Home RemodelingFlooringBathroom and kitchen pricing guideADU Construction in RedmondADU Construction in Issaquah
Free In-Home Consultation

Your next chapter starts at home.

Tell us what you would like to change. Adi visits, measures and listens, and you receive a written, itemized estimate with one point of contact from the first walkthrough to the final details.

WA Reg #AIMBUBL742DO · Bonded and insured ↗
Call (425) 671-2917Pricing Guide