On September 9, 2025, the Broomfield City Council approved Ordinance No. 2265, a significant update to the city’s municipal code that will make accessory dwelling units (ADUs) easier to get approval for on your lot. The ordinance took effect September 16, 2025, and aligns Broomfield’s local rules with Colorado’s new statewide ADU legislation (HB24-1152).
This is an important milestone. Here’s a breakdown of what changed, in both the City’s legal language and in plain English.
Here we go!
Where ADUs Are Allowed
Code 17-32-160(A), (C) says: ADUs are a permitted accessory use on any lot that allows a detached single-family dwelling. They may be internal, attached, or detached.
Setback Requirements
Code 17-32-160(C) says:
- Detached ADUs must meet accessory building setbacks for the zone, but never less than 5 feet from property lines.
- ADUs may not be placed in front of the primary home.
- If attached (or too close to meet separation rules), they must meet principal structure setbacks.
Parking Requirements
Code 17-32-160(E) says:
- No new off-street parking required if the property already meets base zoning parking minimums.
- If the main home falls short, one additional space must be provided for the ADU.
- Tandem parking is permitted.
Size Limits
Code 7-32-160(D) says: ADUs are capped at 50% of the main home’s footprint or 800 sq ft (whichever is less). Every lot is guaranteed at least 500 sq ft, even if the calculation is smaller.
Occupancy & Use
Code 17-32-160(F) says:
- Max occupancy = 2 people.
- The property owner must live on-site.
- Short-term rentals prohibited.
Design Compatibility
Code 17-32-160(G) says: ADUs must visually match the primary home. At least 50% of wall surfaces (including 50% of any street-facing wall) must use similar materials/colors. Entry doors must remain subordinate to the main house.
Utilities & Septic
Code 17-32-160(G), (H) says: ADUs generally share utilities with the primary home. Septic users require sign-off from Broomfield Public Health & Environment.
What Counts as an ADU
Code 17-32-160(J)–(L) says:
- Not allowed: RVs, trailers, shipping containers, or mobile homes.
- Allowed if compliant: Manufactured, modular, or tiny homes on proper foundations, clad to match the main house.
Title Notice
Code 17-32-160(I) says: Owners must record a declaration of use describing the ADU’s size and location. For detached ADUs, this is required before a Certificate of Occupancy is issued.
So, in plain English…
Can I even build one? If you can have a single-family home, you can have an ADU. It could be a basement apartment, a unit over the garage, or a separate little backyard house.
Where can it go? Front yard? Nope. Side yard? Yes. Backyard? Sure! Just keep it at least 5 feet off your property line (more in some zones), and you’re good. This flexibility opens up way more lots than before.
Do I need to pave more parking? Most folks won’t have to touch their driveway. If you’re short on spaces, plan for one more — but you can park cars in a line, which is a huge help on tight lots.
How big can it be? Think: a one-bedroom, a small two-bedroom, or a studio. Even if you’ve got a tiny house, you can still build something meaningful (500 sq ft guaranteed).
Who can live there? No Airbnb side hustle here (sorry!). This is meant for family, long-term tenants, or renters… and you’ve got to live in either the main house or the ADU.
Does it have to match my house? It’s not supposed to stick out like a sore thumb. Your ADU should look like it belongs on your lot (matching paint, siding, roofline, etc.).
How does it run? It runs on your house’s utilities. Septic folks – you’ll need a green light from the health department.
Do I have to file anything? Yes. You’ll need to record a simple note on your property title so it’s clear the ADU exists and is following the rules.
How Broomfield Stacks Up
- Boulder: Went further — ditched owner-occupancy and parking requirements in 2025.
- Denver: Still catching up to state law.
- Broomfield: Kept some restrictions (owner-occupancy, 2-person cap) but modernized setbacks, parking, and design rules.
Translation: Broomfield is moving in the right direction, but not as far as Boulder.
So… What Does This Mean for You?
The good news: Broomfield has lowered the barriers. ADUs are now more doable than ever.
The tricky part: Zoning codes are still zoning codes. It’s easy to get lost in the fine print about setbacks, title declarations, and occupancy caps.
That’s where Olerra comes in. We can…
- Run a feasibility report on your property so you know exactly what’s possible.
- Handle permitting and compliance so you don’t have to argue setbacks with the City.
- Manage the whole process (design, manufacturing, site prep, and installation) so you can focus on the end result.
Bottom line: Broomfield cleared the path. We’ll help you walk it.
Sources & Further Reading
- Ordinance No. 2265, City & County of Broomfield (PDF)
- City & County of Broomfield Rules & Regulations
- Broomfield Enterprise ADU Ordinance Change Article
- Colorado House Bill 24-1152 (ADUs Statewide)
About Olerra
Olerra Living Innovations is redefining backyard living in Colorado. As a state-certified modular ADU manufacturer, we specialize in cold-formed steel construction that delivers unmatched durability: fire-rated, snow-load tested, and engineered for Colorado’s toughest conditions. Our ADUs offer premium finishes, sustainable design, and faster installation than traditional construction.
What sets Olerra apart is our vertically integrated approach. We handle every step: property feasibility, design, permitting, manufacturing, site work, and installation, so homeowners enjoy a seamless experience with fewer delays and surprises. Whether for rental income, multigenerational living, or personal space, Olerra ADUs transform backyards into long-term value.
Connect with Olerra
For more information about the exact cost of your ADU, including permits, administrative process, etc., contact Olerra today. We will help you select the perfect size and design for your modular flat according to the available space on your property. Our process is seamless and will take more than half the burden off your shoulders.
Book a consultation with us today so we can help you out, and you don’t end up wasting any of your time. We will provide you with a free property check and a quote form, so reach out today and avail this great deal.