How Much Does an ADU Cost in Sacramento in 2026?
By Liberty Drafting Studios
A complete breakdown of ADU design and construction costs in Sacramento — from permits to plans to build — so you know exactly what to budget before you start.
If you're thinking about adding an ADU (Accessory Dwelling Unit) to your Sacramento property, the first question on your mind is probably: how much is this going to cost?
The honest answer is — it depends. But after completing over 1,000 residential projects across Greater Sacramento, we can give you a realistic picture of what to expect in 2026.
What Is an ADU?
An ADU is a secondary housing unit on a single-family residential lot. It can be:
- A detached backyard cottage (new construction)
- An attached addition to your existing home
- A garage conversion (turning your garage into living space)
- A JADU (Junior ADU — a unit carved out of your existing home, up to 500 sq ft)
Each type has different cost profiles. Let's break them down.
ADU Cost Breakdown in Sacramento (2026)
1. Design & Plans: $3,500 – $8,000
Before anything gets built, you need permit-ready architectural plans. This is where Liberty Drafting Studios comes in.
Our ADU design fees typically range from $3,500 to $6,500 depending on size and complexity. For a standard 400–800 sq ft detached ADU, expect to pay around $4,000–$5,500 for complete permit-ready drawings.
What's included:
- Site plan
- Floor plan
- Elevations (all four sides)
- Structural details
- Title 24 energy compliance
2. Permit Fees: $5,000 – $15,000
Sacramento County and city permit fees vary significantly based on the ADU's square footage and type. In 2026, typical permit fees run:
- JADU (up to 500 sq ft): $2,000 – $5,000
- Attached ADU (500–1,000 sq ft): $5,000 – $10,000
- Detached ADU (up to 1,200 sq ft): $7,000 – $15,000
Good news: California law (AB 68, SB 13) significantly reduced ADU permit fees for units under 750 sq ft. Many Sacramento homeowners pay under $5,000 in total permit fees for smaller ADUs.
3. Site Work & Utilities: $5,000 – $25,000
Depending on your lot, you may need:
- Utility connections (water, sewer, electrical): $5,000 – $15,000
- Grading and drainage: $2,000 – $8,000
- Driveway or access path: $1,500 – $5,000
This is often the most variable cost category — a flat lot with existing utilities nearby costs far less than a sloped lot requiring new utility runs.
4. Construction: $150,000 – $350,000+
This is the big one. General contractor costs for ADU construction in Sacramento in 2026 run approximately:
- Garage conversion: $80,000 – $150,000
- Attached ADU addition: $150,000 – $250,000
- Detached ADU (new construction): $200,000 – $350,000+
Cost per square foot ranges from $250 to $450/sq ft depending on finishes, contractor, and current material costs.
Total ADU Cost Estimates for Sacramento (2026)
| ADU Type | Low Estimate | High Estimate |
|---|---|---|
| JADU (interior conversion) | $40,000 | $100,000 |
| Garage Conversion | $90,000 | $175,000 |
| Attached ADU | $175,000 | $300,000 |
| Detached ADU | $225,000 | $400,000+ |
Is an ADU Worth It in Sacramento?
In most cases, yes — especially given Sacramento's rental market. A well-designed ADU can generate $1,500 – $2,500/month in rental income, which means a $200,000 investment can pay for itself in 7–10 years while also increasing your property value by $150,000–$250,000.
What Affects ADU Cost the Most?
1. Size — Every additional square foot adds cost. Keep it under 800 sq ft to maximize value.
2. Finishes — Standard finishes vs. high-end finishes can swing costs by $50,000+.
3. Site conditions — Sloped lots, poor soil, or distant utilities all add cost.
4. Contractor selection — Get at least 3 bids. Prices vary widely in Sacramento.
5. Design complexity — A simple rectangular footprint costs less than an L-shaped or multi-story design.
How to Start Your ADU Project
The first step is getting permit-ready plans. Without approved plans, you can't pull permits, and without permits, no reputable contractor will break ground.
At Liberty Drafting Studios, we specialize in ADU design for Sacramento homeowners. We handle everything from the initial site analysis to permit-ready drawings — and we've done it hundreds of times.
Call David directly at 916-694-9949 for a free project review, or use our online calculator to get an instant estimate for your ADU design.
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Written by
David Ardelian, Liberty Drafting Studios
Founder of Liberty Drafting Studios, serving Greater Sacramento with permit-ready architectural plans for ADUs, garage conversions, custom homes, and remodels.
