HSP handled every permit. First rent check arrived exactly when they promised.
San Diego · Tacoma · Lakewood — ADU specialist
ADUs — designed, permitted, and built by one team.
Permitted ADUs and garage conversions for California and Washington homeowners. Free consultation, written proposals, in-house permitting, and a dedicated project manager — with direct owner involvement on every job.
- In-house permitting
- Written proposals & timelines
ADUs. Garage conversions. Permitted and built for the way you live.
From concept to completion
Our services
ADU construction, handled end to end.
Every ADU service under one contractor — design direction, detached ADUs, garage conversions, attached ADUs, junior ADUs, permits and build.
Detached ADU
Standalone backyard ADUs — design, permits, and build under one contract. Rental income or multigenerational living.
Learn moreAttached ADU
ADUs attached to your home — structural engineering, permits, and build under one contract.
Learn moreGarage conversion
Garage-to-ADU conversions — fully permitted, design through finish, under one contractor.
Learn moreJunior ADU
Junior ADUs (JADUs) within your home — up to 500 sqft, fully permitted, with private entrance and kitchenette.
Learn moreWhat we build
Related work we handle — same team, same standard.
From backyard guest houses to garage conversions that generate rental income — we handle every type of ADU project. Read the guide before you call.
Backyard ADUs
Standalone detached ADUs — guest houses, rental units, or multigenerational living. Permitted and built from the ground up.
Read the guideGarage conversions
Convert an existing garage into a fully permitted living unit — kitchen, bath, private entrance, and rental income.
Read the guideRental income
ADUs in San Diego rent for $1,400–$2,400/month. We walk through the rental math and projected ROI at the consultation.
Schedule a consultationJunior ADUs
JADUs — up to 500 sqft within the existing home footprint. Permitted, with private entrance and kitchenette.
Read the guideWhat we build
ADUs. · Garage conversions. · Guest houses. · Rental income. · Permits handled.
Selected projects
Recent ADU work across San Diego and Washington.
A sample of recent ADU projects in San Diego, Tacoma, and Lakewood. Hover any project to preview — full case studies and before/afters available on request.
- 2025
San Diego backyard ADU
Detached 800 sqft backyard ADU — permitted from day one, design through final inspection under one team.
- 2025
North Park garage conversion
Permitted garage-to-ADU conversion — full kitchen, bath, and private entrance. First rent check on schedule.
- 2024
Tacoma backyard ADU
Detached ADU on a Pierce County lot — design, permits, and build under one team.
- 2024
Lakewood ADU
Backyard ADU near American Lake — multigenerational living, design through final inspection.
Before & after
See the transformation.
Drag the slider on any project to compare the before with what we built. Real homes, real scope, real permitted ADUs.
Project gallery
ADU projects across San Diego, Tacoma, and Lakewood.
Drag any tile to reorder. Click to open the full preview — then jump between projects with the floating dock.
San Diego backyard ADU
Detached backyard ADU — 800 sqft, private entrance, full kitchen and bath. Design, permits, and build in-house.
Tacoma backyard ADU
Detached ADU on a Pierce County lot — design through final inspection under one team.
San Diego garage conversion
Permitted garage-to-ADU conversion — North Park. Full kitchen, bath, and private entrance.
Lakewood backyard ADU
Detached ADU near American Lake — design, permits, and build under one contract.
Why us
Why San Diego and Washington homeowners pick us.
In-house permitting
We handle city and county ADU permitting directly in California and Washington — no third-party expediters, no lost weeks. The permit timeline is built into your written proposal so you know what to expect.
Direct owner involvement
The owner is on every project. A dedicated project manager gives you regular on-site updates from start to finish.
Written proposals & timelines
Every project starts with a free consultation and a written proposal: line-item scope, permit timeline, and total cost. Change orders are written and approved before work proceeds.
Service area
Where we work.
Serving San Diego (San Diego County, CA), Tacoma, and Lakewood (Pierce County, WA).
HQ in San Diego, CA
Reviews
What our San Diego and Washington neighbors say.
on Google · 298 reviews
“Our ADU now covers our entire mortgage. This changed our family's life forever.”Sandra & James R. · Google
I was nervous about the process. They made it completely stress-free.
Best financial decision we ever made. HSP found savings we didn't know existed.
About HSP ADU Builders
An ADU team that treats your home like it matters.
Locally owned and cross-state licensed. HSP ADU Builders handles ADU design, permitting, and construction in one place — detached ADUs, garage conversions, attached ADUs, and junior ADUs across San Diego County and Pierce County. Transparent, structured, direct.
Licensed in California and Washington, bonded and fully insured. Every project starts with a free on-site consultation and a written proposal.
Read our story →Learn before you call
The questions homeowners ask before they build an ADU.
In-depth guides answering the most common questions about permitting, costs, rental income, and what to expect — written by a licensed ADU contractor.
Ready to start?
Free consultation. Written proposal. Then we build.
Call 1-888-484-3132 or schedule a free consultation. We'll walk through your project on-site and put a clear scope and timeline in writing.