Can I Build an ADU in Greenwood Village?

Can I build an ADU in Greenwood Village?

Yes. Since June 30, 2025, Colorado’s ADU law (HB24-1152) requires Greenwood Village to allow one accessory dwelling unit on lots zoned for a single-family home. It can be detached, attached or inside the house, and approval is administrative, with no public hearing. Your lot’s setbacks, size limits and utilities decide what fits.

Does Colorado’s ADU law apply to Greenwood Village?

Yes. Greenwood Village is one of the Front Range cities the state lists as a subject jurisdiction under HB24-1152, so it has to follow the state’s ADU rules. The city opposed the bill while it was debated, but since June 30, 2025, a homeowner’s right to build one ADU comes from state law, not a local vote.

Here’s what that means for your property, in plain terms.

What Greenwood Village has to allow

• One ADU on any lot where a single-family home is allowed
• Any of the three types: detached (a backyard cottage or carriage house), attached, or internal (a basement or converted space)
• Approval through an administrative review based on objective standards, with no public hearing and no vote by a board or council

What Greenwood Village can’t require, in most cases

• That the owner live on the property, with narrow exceptions (for example, a short-term rental permit)
• A new off-street parking space for the ADU
• Design or dimension rules so restrictive they effectively block an ADU

What the city can still regulate

• Size: state law protects ADUs in roughly the 500 to 800 square foot range, and the city can require the ADU to be smaller than the main house
• Building, fire, stormwater and utility codes, including proof that water and sewer service are available
• Short-term rentals, impact fees and historic properties

City code updates don’t always keep pace with state law, so the zoning standards for your specific parcel still matter. We check them for every Greenwood Village project before design starts. For a closer look at how these rules work next door, see our guide to ADU permits and zoning in Denver.

What kind of ADU can I build in Greenwood Village, and can my HOA stop it?

You can build a detached, attached or internal ADU, and your HOA can’t ban it outright. Under HB24-1152, HOA covenants that prohibit ADUs on single-family lots are void. HOAs can still set reasonable rules, such as design or material standards, as long as they don’t unreasonably raise costs or effectively block a compliant ADU.

The three ADU types, and where each fits

• Detached ADU (backyard cottage or carriage house). The most private option and the most popular for guests, family or rental income. It needs room for setbacks, utility runs and access. A carriage house built over a new detached garage adds parking and storage while keeping the ADU off the ground floor.
• Attached ADU. Shares a wall with the main house, which can simplify utility connections. Design matters here: the addition should read as part of the original home, not an afterthought.
• Internal ADU. A basement or existing space converted into a separate unit with its own entry. Often the lowest cost per square foot, but ceiling height, egress windows and fire separation have to meet code.

What decides what fits on your lot

• Zoning district setbacks, height limits and lot coverage
• The size of the main house, since the ADU can be required to be smaller
• Where water, sewer, gas and electric service can connect
• Grading, drainage and mature trees
• HOA design standards, which can shape materials, rooflines and placement

Many Greenwood Village homes sit on larger lots than central Denver, which often leaves room for a detached ADU that feels like a true guest house. On high-value properties, an ADU should be designed to match the main home’s architecture and finish level. A well-designed ADU adds to the property; a poorly matched one can work against it.

How much does it cost to build an ADU in Greenwood Village?

A custom ADU built by SDB typically runs $400 to $550 per square foot, so a 500 to 800 square foot unit generally lands between $200,000 and $440,000. Where yours falls depends on the ADU type, site work, utility connections and finish level. Your fixed price comes from a design review of your actual property.

Why online estimates often look lower

You’ll see figures closer to $250 to $365 per square foot for the Denver area. Most of those cover construction only, at builder-grade finishes. They usually leave out design, engineering, permits and project management, and the difference tends to show up later as allowances and change orders. A smaller ADU also costs more per square foot than a house, because it still needs a full kitchen, bathroom, foundation, roof and utility connections.

What moves the price most

• Type: an internal conversion usually costs least; a detached carriage house over a new garage costs most
• Utilities: long runs for water, sewer and electric from the main house add cost quickly
• Site: grading, drainage, access for equipment and tree protection
• Finishes: matching the main home’s materials and design level on high-value properties
• HOA standards: required materials or rooflines can affect cost

How long it takes

An ADU moves through three phases: concept and pricing, design and permitting, then construction. With our process, you get concept plans and a fixed project cost within a few weeks. Permit review time depends on the city’s workload, and construction length depends on the ADU type and site. Detached units take the longest because they’re built from the foundation up.

Who can design and build an ADU in Greenwood Village?

Sustainable Design Build (SDB) designs, permits and builds ADUs in Greenwood Village and across the Denver metro under one contract. We’re a builder-led design-build firm founded in Denver in 2016, with in-house architecture, interior design, permitting and general contracting. That means the people drawing your ADU are the same people pricing and building it.

How we start every ADU: the Project Concept Service

Within a few weeks, you get three things most homeowners wait months for:

1. Buildable drawings you own, based on real measurements of your property
2. A fixed project cost, set at the end of the concept phase, not after permits
3. A realistic permit and construction schedule

Before design starts, we check your parcel’s zoning, setbacks, utilities and HOA standards, so you know what fits before you invest in plans.

Why Greenwood Village homeowners work with SDB

• One team, one point of contact. An assigned project manager handles your ADU from design through final inspection.
• Design that matches your home. Our architecture and interior design team plans the ADU to fit the main home’s style and finish level.
• Fewer surprises. Design and cost move together, so you don’t fall for a plan you can’t afford to build.
• Full visibility.  When working with SDB you receive access to industry-leading project management with our construction tracking applications, complete with client portal. Your client portal shows the schedule, daily logs, photos, budget and change orders in real time.
• Recognized work. Best of Mile High 2024 Best Homebuilder, BusinessRate Best Home Builder 2023 and 2025, and a 2026 Denver Post Best of the Front Range nominee.

See our ADU services, project types and process on our Denver ADU builder page.

Find out what your Greenwood Village lot can hold. Schedule a consultation or call (720) 667-4876.

Sources (for reference; optional to publish)

• Colorado Division of Local Government: Accessory Dwelling Units (HB24-1152 subject jurisdictions)
• Colorado Lawyer: New ADU and Occupancy Limit Laws in Colorado
• Greenwood Village: Tell Legislators to Vote NO on Bills 1152, 1304 and 1313