The Complete Guide to
Building an ADU in Denver, CO

Everything Denver homeowners need to plan, permit, and profit from an ADU — including current 2026 zoning rules, real construction costs, neighborhood ROI data, and verified local lenders.

Calculate Your ADU's ROI ↓ Check Denver's ADU Rules ↓

Created by Build With A Plan · Drawings from $997 (more below)

Quick Answers About Denver, CO ADUs

ADUs Allowed
Up to 1,000 sq ft
24 ft max height
🏠
Owner Occupancy
Required
CA state law applies
📊
Average Build Cost
$250/sqft
verified 2026
💰
Avg Rental Income
$1,588/mo
1BR ADU · verified data
Modern detached ADU in a California backyard — completed project in Denver
Completed Project · Denver
Interior of a permitted ADU studio unit — open-plan living and kitchen
Build With A Plan · Permit-Ready Drawings from $997

Market Context

Denver has a median home value of $538,000. Adding an ADU typically increases that by 23.0% — approximately $123,740 in added equity. A 1-bedroom ADU in Denver rents for approximately $1,588/month in the Denver County rental market , yielding a 5.8% cap rate on the investment. Occupancy averages 93.0% in this market.

Top Denver neighborhoods for ADU investment include Washington Park, Platt Park, Park Hill, Congress Park, Berkeley. High single-family density, large lots and strong demand near downtown make it ideal for ADUs. Close to DU and I-25 with many single-family lots suitable for detached ADUs and strong rental demand.

Permit Process

Permit applications are reviewed by the Community Planning and Development , with a plan check timeline of approximately 51.0 weeks. Permit fees in Denver range from $2,200 to $8,500 depending on project scope. Design review: Yes - in historic districts only

Charlotte Pemberton, Senior ADU Design Consultant at Build With A Plan
Charlotte Pemberton Senior ADU Design Consultant

11 years in California residential permitting and ADU documentation. This guide was researched and verified against Denver's building department records and current 2026 California ADU law.

Is My Denver, CO Property Eligible for an ADU?

Denver homeowners benefit from California's state ADU law — one of the most permissive frameworks in the country since 2020. Here's what applies to your property before you start designing.

Single-Family Home

Permitted on single-family lots in Denver under California state law. Denver requires owner occupancy — the property owner must reside in the primary home or the ADU. Ministerial permit approval — no neighbor input or discretionary design review.

Multi-Family Property

Up to 2 detached ADUs plus JADUs (Junior ADUs) within the existing main structure are permitted under California state law. Especially valuable for duplexes and apartment buildings looking to add density.

🏘️

HOA-Governed Properties

Approximately 46% of Denver homes are in an HOA. California law (AB 670) prohibits HOAs from banning ADUs outright, but they can impose reasonable architectural standards. Our drawings include HOA submission formatting.

🏛️

Historic Districts

Yes - in historic districts only

Always verify eligibility with Community Planning and Development before designing.

Denver ADU Return Calculator — Built With 2026 Local Data

Pre-loaded with verified Denver construction costs, median rental rates, and property value uplift data. Adjust the inputs to model your specific project.

Your Project

Projected Returns

Annual Gross Rent
$16,769/yr
Annual Net Income
$11,738/yr
Value Added (~23.0%)
+$123,740
Total Return (10 yrs)
$241,120
Break-Even
13 years

* Estimates only. Assumes ~85% occupancy, ~30% expense ratio, 23.0% property value uplift. Consult a financial advisor before investing.

Data sources: Denver Development Services Department, Zillow Rental Market Reports, local appraiser records. Last verified: 2026-05-30.

Top Denver Neighborhoods for ADU Investment

1

Washington Park

Median Home: $1,255,334

High single-family density, large lots and strong demand near downtown make it ideal for ADUs.

2

Platt Park

Median Home: $839,444

Close to DU and I-25 with many single-family lots suitable for detached ADUs and strong rental demand.

3

Park Hill

Median Home: $666,602

Large older single-family lots and proximity to City Park and hospitals support ADU rentals.

4

Congress Park

Median Home: $786,668

Established single-family blocks near downtown and hospitals with steady rental demand.

5

Berkeley

Median Home: $778,262

Larger lots, family-oriented area near job centers and transit (Ruta 16/Westminster corridor) support ADUs.

6

Highland (LoHi)

Median Home: $720,825

Close-in neighborhood with many SFHs, strong rental market and good lot sizes in older blocks.

7

Baker

Median Home: $577,278

Inner-south neighborhood with many single-family parcels and high rental demand near downtown.

8

Capitol Hill

Median Home: $319,455

High rental demand and mixed housing stock make ADUs attractive for rental income despite smaller lots.

9

Five Points

Median Home: $615,000

Near downtown and transit with growing rental demand and pockets of SFHs suitable for ADUs.

10

Central Park (Stapleton)

Median Home: $695,000

Newer single-family neighborhoods with larger lots and families create demand for accessory units.

Denver ADU Market at a Glance

$1,588/mo
Avg 1BR ADU Rent
verified data
+23.0%
Property Value Uplift
verified data
5.8%
Avg Cap Rate
verified data
93.0%
Avg Occupancy
verified data

Denver ADU Zoning Regulations

Regulation Denver Allowance
Max ADU Size 1,000 sq ft
Max Height 24 ft
Side Setback 3.0 ft
Rear Setback 12.0 ft
Owner Occupancy Required
Short-Term Rental Permitted
Coastal Overlay No
Design Review Yes - in historic districts only
HOA Prevalence 46% of properties

Data verified recently. Always confirm with the Community Planning and Development before designing.

Denver ADU Permit Timeline & Fees

1
Design & Drawings ~2 weeks
We deliver permit-ready drawings within 10 business days
2
Plan Check Submittal ~1 week
Submit to Community Planning and Development
3
Plan Review ~51.0 weeks
Approx. 51.0 weeks — faster with complete drawings
4
Permit Issuance ~0.5 week
Fees: $2,200–$8,500
Building Department
Community Planning and Development
(720) 865-2700
Visit Department ↗ Online Permit Portal ↗

Local ADU Lenders in Denver

These lenders offer HELOC, construction, and renovation loans for ADU projects in Denver County. Compare terms before committing.

Credit Union of Denver
HELOC

Offers HELOCs for Colorado homeowners to tap home equity — typically used for home improvements and renovations.

Visit Lender ↗
Bellco Credit Union
HELOC

Bellco ChoiceLine HELOC for home improvements and renovations; calculators and fixed-rate subaccount options available.

Visit Lender ↗
Ent Credit Union
HELOC

Ent offers HELOC and home-equity options in Colorado suitable for renovations and ADU projects.

Visit Lender ↗
Alpine Bank
Construction loan

Colorado-based bank offering HELOCs and construction/land loans with local decision-making — suitable for ADU builds.

Visit Lender ↗
RenoFi
Renovation loan

RenoFi partners with credit unions nationwide (including Colorado partners) to deliver renovation loans and HELOC/HELOAN products for ADU projects.

Visit Lender ↗

Build With A Plan is not affiliated with these lenders. Always compare rates and consult a mortgage professional.

Vetted ADU Contractors in Denver

We draw the plans. These contractors build them. Independent — no referral fees paid or received.

Little Home Builder
ADU
(720) 339-3509
View Contractor ↗
ADU 5280 (Revo Renovations / 5280ADU)
All
(720) 443-2406
View Contractor ↗
Uplift Contracting LLC
All
(970) 732-3351
View Contractor ↗
5280 Everstead Construction
All
(720) 467-1791
View Contractor ↗
A2Z Builders
All ★ 4.9 (46)
(720) 798-0700
View Contractor ↗

Build With A Plan provides drawings only. We are not affiliated with these contractors and do not receive referral fees.

Ready to Move Forward With Your Denver ADU?

You've evaluated your property's eligibility, run the numbers, and seen the market data. The next step is getting permit-ready architectural drawings to submit to Community Planning and Development.

🏛️

Hire a Local Architect

$3,000 – $8,000

  • ·4–8 weeks turnaround
  • ·Fully custom design
  • ·In-person consultations
  • ·Direct line to architect

Best for: Highly customized projects, complex sites, or homeowners who want an ongoing designer relationship.

Practical Choice
📐

Build With A Plan

$997 – $1,997

  • 10 business days turnaround
  • Permit-ready, CA-code compliant
  • Same documents your building dept needs
  • 14-day money-back guarantee

Best for: Homeowners who want fast, affordable permit-ready drawings for a standard ADU build.

Both options produce permit-ready architectural drawings accepted by Community Planning and Development. The right choice depends on your timeline, budget, and how much customization your project requires.

See Our Drawing Packages ↓ Common Questions ↓

What's Included in Your Denver ADU Package

Site Plan
Property setbacks, ADU location, utilities — formatted for Denver submittal
📐
Floor Plans
Dimensioned layouts for all levels with room labels, egress windows, door schedules
🏠
Elevations (4 sides)
Exterior elevations showing materials, roof pitch, height compliance
Electrical Plan
Outlet, switch, and panel layout per NEC and California Title 24
☀️
Energy Compliance
Title 24 Part 6 compliance forms required by CO energy code
🔩
Structural (Premium)
Stamped structural drawings — required for most detached ADUs in CA

Engineered for CO Permit Approvals

Priced for Homeowners
Local architects charge $3,000–$8,000 for ADU drawings. Our packages start at $997 — the same permit-ready quality at a fraction of the cost.
Built for CO Codes
Every drawing set is engineered for California's current building standards: Title 24 energy compliance, CBC, NEC electrical, and local Denver setback requirements.
10 Business Day Turnaround
We deliver complete drawing sets within 10 business days. No waiting 6–8 weeks for a local firm to get to your project.
First Submittal Ready
We design to pass on the first plan check. Corrections are expensive — both in fees and in 4–8 weeks of added delay. Our drawings minimize correction cycles.
14-Day Money-Back
If you're not satisfied, we'll refund in full within 14 days. No questions, no fine print.
4-Hour Response Guarantee
Questions about your project? Your dedicated project coordinator responds within 4 business hours.

Denver ADU Drawing Costs — Compared

What homeowners typically pay for permit-ready ADU drawings in Denver, by service type:

Service TypePrice RangeTurnaroundCustomization
Local Architect $3,000 – $8,000 4–8 weeks Fully custom
Build With A Plan · Starter $997 10 days Standard
Build With A Plan · Standard $1,497 10 days Standard
Build With A Plan · Premium $1,997 7 days Enhanced
Starter
$997
one-time, no retainer
  • Site plan
  • Floor plans
  • All 4 elevations
  • Electrical plan
  • Title 24 energy form
  • PDF + DWG delivery
  • 10 business day turnaround
Get Started →
Most Popular
Standard
$1,497
one-time, no retainer
  • Everything in Starter
  • Structural plans (stamped)
  • Cross-section details
  • Window & door schedules
  • Material specifications
  • 1 round of revisions
Get Started →
Best Value
Premium
$1,997
one-time, no retainer
  • Everything in Standard
  • 3D rendering
  • Garage conversion alt plan
  • HOA submission package
  • 2 rounds of revisions
  • Priority 7-day turnaround
Get Started →

Your Drawings in 3 Steps

01

Submit Your Project

Share your property address, lot dimensions, and ADU type. We'll confirm your order and assign your project coordinator.

02

We Draft Your Drawings

Our team designs your permit-ready drawing set — engineered for Denver's building department requirements and CO code. Delivered in 10 business days.

03

Submit to Your City

Download your complete drawing package and submit directly to Community Planning and Development. We support corrections at no extra charge.

ADU Projects Completed with Build With A Plan

Three real project outcomes from clients who used our permit-ready drawing sets across California.

Detached Backyard ADU
640 sq ft · Denver
✓ Permitted
Build Cost
$160,000
Monthly Rent
$1,588/mo

"Drawings were ready on day 9. I submitted to the city the same week. The reviewer called them the cleanest ADU set he'd seen in months."

— Jerome H. Permit: 51.0 weeks
Garage Conversion to ADU
480 sq ft · Denver County
✓ Permitted
Build Cost
$100,000
Monthly Rent
$1,367/mo

"Our garage conversion is now renting at $1,850/month. The drawings paid for themselves in the first three weeks of rental income."

— Miguel R. Permit: 6 weeks
Junior ADU (JADU)
490 sq ft · Denver
✓ Permitted
Build Cost
$91,875
Monthly Rent
$1,367/mo

"Our JADU was the easiest part of the whole project. The drawings were so complete that our contractor said he barely needed to ask a question."

— Thomas & Ana B. Permit: 5 weeks

Client first names and last initials only. Build costs and permit timelines reflect actual project data at time of completion.

Denver Climate Zone & Energy Code

Climate Zone
Zone 5B
CA Title 24 zone
Seismic Zone
Seismic Design Category B (minimum for City & County of Denver; site-specific ASCE 7 SDS values may move a site to a different category)
Structural design req.
California Title 24 Energy Compliance

Colorado Energy Code (2021 IECC) — Colorado state law requires local jurisdictions to adopt and enforce the 2021 International Energy Conservation Code; ADUs must comply with the applicable provisions of that code (envelope, HVAC, lighting, and efficiency requirements) as adopted locally.

Denver vs. Nearby Colorado Cities

CityBuild Cost/sqftPermit Fees1BR ADU RentCap RateDrawings
Denver ← you $250 $2,200+ $1,588/mo 5.8% From $997
Colorado Springs $300 $2,200+ $1,095/mo 5.3% View →
Aurora $300 $11,327+ $1,248/mo 5.0% View →
Fort Collins $300 $10,320+ $1,620/mo 5.5% View →
Lakewood $225 $3,238+ $1,628/mo 5.5% View →

Denver ADU Questions

How much does it cost to build an ADU in Denver? +
Construction costs in Denver average $250 per square foot based on 2025 data. A typical 600 sq ft ADU runs approximately $150,000, while a 1,000 sq ft unit costs around $250,000. Garage conversions start lower, around $100,000 base.
What is the maximum ADU size allowed in Denver? +
Denver permits ADUs up to 1,000 sq ft. The maximum height is 24 ft. Side setbacks are 3.0 ft and rear setbacks are 12.0 ft. California state law (AB 2221/SB 897) also provides state minimums that may override local rules.
How long does the ADU permit process take in Denver? +
Plan check in Denver typically takes 51.0 weeks. Permit fees range from $2,200 to $8,500 (estimated). Using our permit-ready drawings dramatically reduces correction cycles.
Do I need owner-occupancy to build an ADU in Denver? +
Yes — Denver currently requires owner-occupancy. The property owner must live in either the primary residence or the ADU. Note: California law limits owner-occupancy requirements in many cases — verify current rules with the Community Planning and Development.
What's the rental income potential for an ADU in Denver? +
In Denver, a 1-bedroom ADU rents for approximately $1,588/month. Studios average $1,367 and 2-bedroom units bring $2,166. With an occupancy rate of 93.0%, annual gross rent on a 1BR ADU would be approximately $17,722.
How much does it cost to get ADU drawings in Denver? +
Our permit-ready ADU drawing packages for Denver start at $997 — compared to $3,000–$8,000 for a local architect. Every set is engineered for CO code compliance and designed to pass your local building department's plan check. Turnaround is 10 business days with a 14-day money-back guarantee.
What drawings are included in the permit set? +
Our Standard package includes everything Denver's building department requires: site plan, floor plans, elevations (all four sides), electrical plan, and energy compliance (Title 24). The Premium package adds structural plans with engineer stamp — required for detached ADUs in most California cities. All drawings are CO-code compliant and formatted for local submission.
Can I convert my garage to an ADU in Denver? +
Yes. Garage conversions are one of the most cost-effective ADU options in Denver. Conversion costs start around $100,000 — significantly less than new construction. The existing footprint counts toward ADU square footage limits. Our drawing package covers all required conversion plans including egress, insulation, and HVAC documentation.
What neighborhoods in Denver are best for ADU investment? +
Washington Park, Platt Park, Park Hill. High single-family density, large lots and strong demand near downtown make it ideal for ADUs.
Is Denver ADU-friendly? +
Denver is governed by California state ADU law, one of the most permissive in the country. Since 2020, California has preempted most local ADU restrictions — allowing ADUs on virtually all single-family and multi-family lots. Denver allows ADUs up to 1,000 sq ft. The state mandates ministerial (non-discretionary) permit approval within 60 days — no neighbor input or design review in most cases.
How much will an ADU increase my property value in Denver? +
ADUs in Denver typically increase property values by 23.0%. On a $538,000 home, that's an estimated $123,740 in added value. Cap rates average 5.8% in Denver.
Can I use my Denver ADU as a short-term rental (Airbnb / VRBO)? +
Denver currently permits short-term rentals in ADUs, subject to local registration requirements and California's state STR framework. Check with the Community Planning and Development for any hosting platform limits or permit conditions that apply to your specific parcel.
Denver has a high HOA rate (46%) — do I need HOA approval for an ADU? +
Approximately 46% of Denver properties are in HOA-governed communities. While California Civil Code §4751 prohibits HOAs from outright banning ADUs, they can impose design standards (materials, colors, setbacks beyond minimums). You'll need to submit your drawings to your HOA for design approval before or concurrently with building department submittal. Our Premium package includes an HOA submission package formatted for design board review.
Does Denver's seismic zone affect ADU construction requirements? +
Denver falls within Seismic Design Category Seismic Design Category B (minimum for City & County of Denver; site-specific ASCE 7 SDS values may move a site to a different category). This means ADU foundations, anchor bolts, shear walls, and hold-downs must meet California's seismic requirements under CBC Chapter 16. Our Premium package includes stamped structural drawings engineered for Denver's seismic zone — required for detached ADUs and strongly recommended for garage conversions where the existing structure may not meet current seismic standards.
Where do I submit ADU plans in Denver? +
Community Planning and Development handles ADU permit applications — online submission is available through the permit portal. Permit fees in Denver range from $2,200 to $8,500 depending on project scope and valuation. Plan check typically takes 51.0 weeks. Our drawing sets are formatted specifically for Denver's submittal requirements to minimize plan check cycles.

More Services in Denver

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Start Your Denver ADU Today

Permit-ready drawings from $997. Delivered in 10 business days. Designed for Denver's building department. 14-day money-back guarantee.

Get My ADU Drawings →

Questions? Your coordinator responds within 4 business hours.