Contact Us
(303) 833-4715
Contact Us
(303) 833-4715

Northern Denver & Front Range's Premier Design-Build Firm

Additions and ADUs in Commerce City, CO

Finally Room for the People and Plans That Matter Most

Start Planning Your Project

Why Commerce City Homeowners Choose Christie's

Because the Home You've Built
Should Finally Have Room for Everyone In It

For more than 25 years, Christie’s has helped homeowners create space that genuinely changes how the household runs. A self-contained ADU where your parent can be close without either of you losing your own front door. A second-story addition that finally gives returning adult children, or a live-in caregiver, real separation from the main house. A garage conversion that stops sitting empty and starts pulling its weight as a fully finished living space.

At Christie’s Design/Build Remodeling, we know Commerce City’s 2025 ADU code change opened a door most homeowners here have never walked through before. The dual-track process, city plan check and independent HOA architectural review, is genuinely new territory for this market, and we walk you through every step of it with straight answers and no surprises. Whether your home is a ranch in the older central core or a newer subdivision property in Buffalo Run or Reunion, we plan additions and ADUs around what your lot, your structure, and your family actually need.

In Business

25+ Years

Helping Commerce City homeowners navigate ADUs, multi-generational additions, and the new permitting landscape with clarity and confidence.

Our Model

One Team

Your Commerce City addition or ADU moves through one coordinated team from early design and HOA review through construction, finishing, and the final walkthrough.

Where We Work

Commerce City, CO

Serving homeowners throughout Buffalo Run, Reunion, River Run, Hazeltine, Adams City, and established neighborhoods across Commerce City.

Peace Of Mind

5-Year Warranty

Your new addition or ADU in Commerce City stays protected after construction, so you can settle into the space with genuine confidence.

What Makes Additions & ADUs Different In Commerce City

More Space Has to Feel
Like It Was Always Part of the Plan

Adding onto a Commerce City home, or building an ADU in the backyard, means understanding the city you’re actually working in, not just the one on paper. Newer homes in Buffalo Run and Reunion bring 200-amp service and unfinished basements that are practically ready to become something; older ranch homes closer to the central core may need panel upgrades, foundation reviews, and a structural conversation before a single wall gets moved. Commerce City’s 2025 Land Development Code finally opened the door to ADUs and additions that simply weren’t possible here before, but that also means most homeowners are navigating this process for the first time with no local precedent to lean on. We walk the full sequence with you, city plan check, HOA architectural review if it applies, and every decision in between, so the result feels like it was always part of your home.

.01

Commerce City Homes Span Two Eras

Newer subdivision homes and older ranch-core properties each open up different possibilities for added space. We look at your specific lot, structure, and HOA situation before anything else gets decided.

.02

Your Home's Era Shapes the Path

Older ranch homes in Commerce City’s central core often carry structural and mechanical realities that shape every addition decision. Knowing those conditions early means the new space connects the way it should.

.03

Aging Panels and Systems Need Checking

Older Commerce City homes can hide outdated wiring or undersized panels behind their walls. Catching those realities during design keeps your budget and your timeline intact.

.04

Hail and Freeze-Thaw Drive Material Choices

Commerce City’s hail seasons and hard freeze-thaw cycles mean exterior material choices on any addition or ADU carry real durability stakes. We factor those conditions into roofing, siding, and foundation drainage from the very first design conversation.
See Our Work

Commerce City, CO Neighborhoods

More Room Without Leaving
the Commerce City You Call Home

Commerce City is full of homes where families have already put down real roots, and that’s exactly why an addition or ADU can carry so much more weight than just adding a room. Some households in the older ranch core are running out of space without any obvious place to expand, and a rear bump-out or in-law suite is the only path forward. Others in Reunion or Buffalo Run have the square footage but no separation, no private entry, no self-contained space for a parent or an adult child stepping back home. The 2025 code change that finally allowed ADUs in Commerce City opened a door most homeowners didn’t even know existed yet, and navigating that new permitting path alongside HOA review takes someone who knows the actual sequence. Lot size, existing structures, setbacks, and whether your neighborhood is HOA-governed all shape what’s genuinely buildable before a single design decision gets made. We start every project by asking what kind of household arrangement would make staying here feel right, not just for today, but for the years ahead.

Buffalo Mesa

Give Your Buffalo Mesa Home the Space Your Family Has Outgrown

Buffalo Mesa was built for families, and the families who stayed are the ones who’ve watched those needs quietly shift over the years. When your post-2000 construction home has the bones but not quite the layout, a well-planned addition or ADU can deliver the separation a returning adult child or aging parent actually needs, a private entry, a real kitchen, a space that feels like theirs. The Metropolitan District’s design review is part of the process here, and we work through those architectural standards from the first sketch so nothing surprises you later.

Turnberry

Grow the Space Without Changing What Your Family Already Loves About It

Families in Turnberry picked these KB Home floor plans because they work, good bones, modern systems, and a layout that made sense on move-in day. What’s missing now isn’t the home itself, it’s the space that didn’t exist yet: a private in-law suite so a parent can move in with their own entry and their own kitchen, a dedicated ADU tucked behind the main house for a returning adult child or a rental tenant, or a primary suite addition that finally gives you the retreat this neighborhood’s price point always promised. We design around Turnberry’s covenant standards and architectural review process from day one, so the addition fits the home it’s attached to, and sails through HOA approval without surprises.

Fronterra Village

More Room for the People Who Matter Most

Homes in Fronterra Village were built with solid bones and real potential, and that unfinished basement sitting beneath your feet is exactly where a self-contained in-law suite or private ADU living space can take shape. Because the neighborhood runs under HOA architectural oversight, exterior work on additions needs to align with the community’s established look, and that’s something we navigate for you from the first design conversation. Whether you’re finishing below grade for a multi-generational suite or adding on to create the separation your household genuinely needs, every detail, materials, entry points, interior flow, gets considered as part of the whole home.

Reunion

Make Room for What's Coming Next

Even newer homes in Reunion can start to feel tight once life shifts in a direction you didn’t plan for, a parent who needs to be closer, an adult child back home, or a rental opportunity you’re ready to act on now that Commerce City’s 2025 ADU rules finally make it possible. The modern construction here is actually an advantage: updated panels, current-code framing, and unfinished basements or oversized garages that are genuinely ready to become something more. We work around Reunion’s HOA architectural standards, your lot’s setbacks, and the city’s plan-check process so the addition or ADU fits the neighborhood and supports the household arrangement you’re building toward.

Buffalo Run

Make Room for the People You're Building This Life Around

Buffalo Run homeowners put down roots here for the long haul, the golf course, the park, the neighborhood feel, and when the family arrangement shifts, an addition or ADU becomes the natural next move rather than a reason to leave. Maybe your parent needs a place that’s close but genuinely their own, with a private entry and a full kitchen rather than just a spare room down the hall. Maybe an adult child is coming back and everyone needs real separation to make that work well. Because Buffalo Run is HOA-governed across multiple subdivisions, we start every project with an architectural review read so you’re not redesigning mid-process, your addition fits the neighborhood from day one.

Our Commerce City Additions & ADU Process

From the First Conversation to the Day You Move In

Adding an addition or ADU in Commerce City right now means navigating a permitting landscape that most homeowners here have never touched before, because until 2025, these projects simply weren’t allowed. An older ranch in the central core faces a completely different set of structural and mechanical realities than a newer home in Reunion or Buffalo Run. Our process walks every project through site evaluation, design, city plan check, HOA review where required, construction, and final completion, keeping each step clear so the space you end up with genuinely fits the life you were planning for.

Start Planning Your Project
(303) 833-4715

.01

Site & Structure Review

Every Commerce City addition or ADU starts with a serious look at the property itself. We evaluate your lot size, setbacks, existing structure, and how the 2025 Land Development Code rules apply to your specific situation. For newer subdivision homes in Buffalo Run or Reunion, that often means detached ADU feasibility; for older ranch homes in the central core, it may mean a rear bump-out or second-story path. Understanding that before design begins keeps the project grounded in reality from day one.

.02

Goals & Design Direction

Before plans take shape, we sit down and talk through what this space actually needs to do for your household. Maybe it’s a private entry and a full kitchen for your mom, or a self-contained unit your returning adult child can genuinely settle into. We think through separation, circulation, and how the new space will feel relative to your existing Commerce City home, so nothing gets designed before we understand what really matters.

.03

Detailed Project Planning

Once the direction is clear, we translate it into a buildable plan your property can actually support. Foundation conditions, framing requirements, electrical service, plumbing, and interior layout decisions all get worked out around your specific home, not a generic template. For Commerce City’s older ranch stock that may mean a panel upgrade alongside the design; for newer HOA-governed homes, it means coordinating material selections with your architectural review standards before anything gets submitted.

.04

Permits & Trade Coordination

Before construction begins, we handle the dual-track approval process that Commerce City homeowners are navigating for the first time in 2025. That means filing with the Building Safety Division for the city’s plan check and, where your HOA requires it, preparing a separate architectural review submission on its own timeline. Keeping both tracks organized and moving together is what prevents the months of delay that catch homeowners off guard when they manage it themselves.

.05

Construction & Communication

With city and HOA approvals in place, your addition or ADU starts taking real shape. Framing, insulation, mechanical systems, drywall, flooring, cabinetry, and finishes all move forward under one coordinated team. Whether we’re building a detached ADU in your backyard, a primary suite above the main floor, or an in-law conversion inside the existing structure, you stay informed at every stage without having to chase anyone for answers.

.06

Final Review & Completion

As construction wraps up, we walk the finished addition or ADU with you and go through the details together, not a quick handoff, a real review. We confirm finishes, work through any remaining items, and make sure the new space connects the way it should to the rest of your home. The goal is that whoever moves in, your parent, your adult child, your tenant, steps into something that already feels complete and ready for them.

Our Commerce City Additions & ADU Process

From the First Conversation to the Day You Move In

Adding an addition or ADU in Commerce City right now means navigating a permitting landscape that most homeowners here have never touched before, because until 2025, these projects simply weren’t allowed. An older ranch in the central core faces a completely different set of structural and mechanical realities than a newer home in Reunion or Buffalo Run. Our process walks every project through site evaluation, design, city plan check, HOA review where required, construction, and final completion, keeping each step clear so the space you end up with genuinely fits the life you were planning for.

.01

Site & Structure Review

Every Commerce City addition or ADU starts with a serious look at the property itself. We evaluate your lot size, setbacks, existing structure, and how the 2025 Land Development Code rules apply to your specific situation. For newer subdivision homes in Buffalo Run or Reunion, that often means detached ADU feasibility; for older ranch homes in the central core, it may mean a rear bump-out or second-story path. Understanding that before design begins keeps the project grounded in reality from day one.

.02

Goals & Design Direction

Before plans take shape, we sit down and talk through what this space actually needs to do for your household. Maybe it’s a private entry and a full kitchen for your mom, or a self-contained unit your returning adult child can genuinely settle into. We think through separation, circulation, and how the new space will feel relative to your existing Commerce City home, so nothing gets designed before we understand what really matters.

.03

Detailed Project Planning

Once the direction is clear, we translate it into a buildable plan your property can actually support. Foundation conditions, framing requirements, electrical service, plumbing, and interior layout decisions all get worked out around your specific home, not a generic template. For Commerce City’s older ranch stock that may mean a panel upgrade alongside the design; for newer HOA-governed homes, it means coordinating material selections with your architectural review standards before anything gets submitted.

.04

Permits & Trade Coordination

Before construction begins, we handle the dual-track approval process that Commerce City homeowners are navigating for the first time in 2025. That means filing with the Building Safety Division for the city’s plan check and, where your HOA requires it, preparing a separate architectural review submission on its own timeline. Keeping both tracks organized and moving together is what prevents the months of delay that catch homeowners off guard when they manage it themselves.

.05

Construction & Communication

With city and HOA approvals in place, your addition or ADU starts taking real shape. Framing, insulation, mechanical systems, drywall, flooring, cabinetry, and finishes all move forward under one coordinated team. Whether we’re building a detached ADU in your backyard, a primary suite above the main floor, or an in-law conversion inside the existing structure, you stay informed at every stage without having to chase anyone for answers.

.06

Final Review & Completion

As construction wraps up, we walk the finished addition or ADU with you and go through the details together, not a quick handoff, a real review. We confirm finishes, work through any remaining items, and make sure the new space connects the way it should to the rest of your home. The goal is that whoever moves in, your parent, your adult child, your tenant, steps into something that already feels complete and ready for them.
Start Planning Your Project
(303) 833-4715

What Commerce City Homeowners Want From Their Addition or ADU

More Room for the
Family You're Holding Together

Addition and ADU projects in Commerce City are almost never about square footage for its own sake. Most homeowners are working through something that showed up at the dinner table: a parent who needs to be closer, an adult child who came back and has nowhere to land comfortably, or a household that simply ran out of room without any obvious place to grow. Commerce City’s 2025 code update opened the door to ADUs for the first time, which means many homeowners here are starting this conversation fresh, with no neighbors who’ve been through it and no local roadmap to follow. What they want most is a setup that gives everyone in the family real independence, real privacy, and a home that finally matches the way they actually live.

Room for the Whole Family

Finally, the Right Fit

In Commerce City's newer master-planned subdivisions like Reunion and River Run, many homes were designed for one household, not two generations under one roof. A well-planned ADU or primary suite addition can give everyone the space and privacy they need without anyone having to leave the neighborhood they already call home.

Layouts That Actually Flex

Space You Grew Into

Older ranch homes in Commerce City's central core were built for a smaller, simpler household. A rear bump-out or second-story addition can bring better flow and real flexibility without pulling the family away from the neighborhood they love.

Built-In Storage That Works

A Door of Their Own

Newer Commerce City lots in neighborhoods like Buffalo Run and Reunion often have more room than homeowners realize. A thoughtful addition or detached ADU can layer in storage, laundry, and private living space without crowding the yard everyone already enjoys.

Genuine Separation, Real Privacy

Close, Still Independent

For homeowners in Reunion and Buffalo Run, an ADU or private in-law suite can make multigenerational living feel sustainable instead of strained. A private entry, full kitchen, and dedicated living space let family members stay genuinely close without stepping on each other.

Built for Hail Country

Built for Colorado Seasons

Commerce City additions need to hold up to hail, hard freezes, and muddy Colorado seasons without losing their finish or their function. Durable siding, impact-rated roofing, and practical interior materials keep the new space looking and living well for the long haul.

What To Consider When Building An Addition or ADU in Commerce City

Plan for the Space Your Family
Actually Needs Next

An addition or ADU can completely change how a Commerce City home works for the people living there, but the best projects start with more than a layout sketch. A newer home in Reunion or Buffalo Run may offer a completely different path than an older ranch in the central core, while your lot size, existing systems, HOA covenants, and utility placement all shape what’s genuinely buildable. Before design begins, it helps to be clear about what the new space needs to solve, who it serves long-term, and what will make it feel right years after the crew packs up and leaves.

Who is this space really for, and what does their daily life look like inside it?

Before you think about square footage or floor plans, sit with that question honestly. If it’s your mom, picture her making coffee in the morning without walking through your kitchen to do it. If it’s a tenant, think about what makes a rental feel like a home versus a room. The clearest projects start when the homeowner can describe a normal Tuesday in the finished space, that picture shapes every decision that follows.
Commerce City’s housing stock splits pretty sharply. If you’re in Buffalo Run or Reunion with a newer two-story and an unfinished basement, you’ve got a genuinely strong foundation to work from. If you’re in an older ranch in the central core, the path looks different, smaller lot, older systems, maybe a panel upgrade in your future. Neither situation is a dealbreaker, but knowing which one you’re standing in before you start designing saves a lot of recalibration later.
This is the one that catches Commerce City homeowners off guard more than any other. The city’s 2025 code change opened the door for ADUs, and that’s genuinely exciting, but if your home is in one of the newer master-planned communities, your HOA runs its own architectural review process on a completely separate timeline. City approval and HOA approval are two different tracks, and both have to clear before construction starts. Knowing that upfront keeps your timeline expectations grounded in reality.
It’s easy to design for the immediate need: the parent moving in this fall, the adult child home for now. The better question is what the space looks like when circumstances shift. Wider doorways and a zero-threshold shower cost almost nothing to add during construction and extend the suite’s useful life for decades. A detached ADU built with a private entry and full kitchen works for family today and a tenant tomorrow. The spaces that hold their value, and their usefulness, are the ones that were planned for more than one chapter.

Our Reviews

Trusted by Commerce City Homeowners
With the Spaces Their Families Depend On

Choosing a team for an addition or ADU in Commerce City means trusting someone to guide you through a process most homeowners here have never faced before. You’re trusting them with your home, your family’s arrangement, and a space that needs to work for years to come. Our reviews reflect exactly the care and honesty Christie’s brings to every Commerce City project, from that very first conversation through the final walkthrough.
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Areas We Service Across Commerce City

More Space
Right Where Your Family Needs It

Across Commerce City, homeowners are figuring out how to make the house they already own work for a household that keeps growing and changing, whether that means a private suite for an aging parent in a Buffalo Run home with an unfinished basement, or a rear addition on an older ranch in the central core that finally gives everyone breathing room. From the newer master-planned neighborhoods in the north to the post-war streets closer to the city’s original grid, every property brings a different set of possibilities. Christie’s meets you where your home actually is, the lot, the structure, the HOA rules, the life you’re building, and helps you find the path forward that genuinely makes sense.
  • Ralston Valley
  • Oberon
  • Pomona Lakes
  • Whisper Creek
  • Spring Mesa
  • Olde Town Arvada
  • Allendale
  • Lake Arbor
  • Scenic Heights
  • Alta Vista
  • Club Crest
  • Hackberry Hill
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(303) 833-4715

Other Areas We Service

Weld County

Greeley, CO
Erie, CO
Fort Lupton, CO
Firestone, CO
Frederick, CO

Boulder County

Boulder, CO
Lafayette, CO
Longmont, CO
Louisville, CO

Adams County

Brighton, CO
Northglenn, CO
Thornton, CO

Jefferson County

Arvada, CO
Westminster, CO

Broomfield County

Broomfield, CO

Larimer County

Loveland, CO
Windsor, CO

Commerce City Addition & ADU Frequently Asked Questions

The Questions Behind
Adding Space That Actually Works for Your Family

Adding onto a home you already love raises a whole different set of questions when the rules are brand new. In Commerce City, ADUs only became legal in 2025, so most homeowners here are starting from scratch, without neighbors or family members who’ve been through the process before. The answers depend on your lot, your HOA status, your home’s age and systems, and whether you’re thinking attached or detached. These are the questions we hear most from Commerce City homeowners who are ready to make room for what their family actually needs right now.

Still Have Questions?
We're Here To Help.

Contact Us
(303) 833-4715

Did Commerce City really just legalize ADUs, and what does that mean for me?

Yes, really. Commerce City’s 2025 Land Development Code update was the first time ADUs were permitted on single-family lots in the city. That’s a significant change, and it means most homeowners here are navigating this process with no local precedent to lean on. The good news is that the rules are clear: one ADU per single-family lot, a maximum size of 1,000 square feet or 75% of your primary home’s floor area (whichever is smaller), and a 22-foot height limit for detached units. The less obvious news is that city approval and HOA approval are two separate tracks, and both have to happen before a shovel goes in the ground.
If you submit a complete, code-compliant drawing set to the Building Safety Division on the first try, plan check takes approximately six weeks. That six-week window assumes everything is in order, which is why the quality of your design documents matters so much. Incomplete or non-compliant submittals get kicked back and restart the clock. On top of city plan check, if your property is in an HOA-governed community (which applies to roughly 44% of homes here, including most of Buffalo Run, Reunion, and River Run), you’ll need architectural review committee approval running on a completely separate timeline. Full project timelines for a custom ADU or significant addition run nine to eighteen months when design, permitting, and construction are properly sequenced.
Not necessarily, but it does mean you have an additional approval layer that runs independently of the city permit. Your HOA’s architectural review committee evaluates the design for consistency with neighborhood standards, and they typically require professional drawings to even submit. The outcome of that review can affect exterior materials, roofline design, entry placement, and other elements that directly shape how livable the finished space is. It’s one of the most common surprises homeowners encounter, and one of the best reasons to work with a design-build team that knows how to prepare submissions that hold up under HOA scrutiny before you invest months in city plan check.
Under current Commerce City rules, the answer is no. Water, sanitary service, and electrical cannot be separately metered for the ADU. The unit shares utility service with the primary dwelling. This is a meaningful operational consideration if you’re planning to rent to an unrelated tenant, it affects how you structure billing and how your mechanical systems are designed. It’s not a dealbreaker, but it’s a detail that shapes the project from the inside out, and it’s something to work through with your design team before you finalize the unit’s layout and systems.
You can, but the starting point looks different than it does for a newer subdivision home. Older ranch and minimal-traditional homes in Commerce City’s central core often have 100-amp electrical panels, crawl-space or slab-on-grade foundations, and smaller lots, all of which shape what’s structurally and mechanically feasible. A second-story addition on a home like yours requires a full engineering review of the existing foundation and wall framing before design even begins. Panel upgrades from 100-amp to 200-amp service are frequently part of the scope. None of these are showstoppers, they’re just honest line items that a good design-build team surfaces early so they don’t show up as surprises midway through.
A finished basement bedroom is a place to sleep. A premium in-law suite is a place to live, and that distinction is the whole point. What makes the difference is genuine separation: a private exterior entry that doesn’t route through your home, a full kitchen (not a kitchenette), in-unit laundry, a dedicated HVAC system, and sound attenuation between the two spaces. If you’re housing an aging parent, that privacy and independence is what makes the arrangement sustainable long-term, for them and for you. If you’re planning to rent the space, that same level of finish and separation is what commands strong rental rates and keeps good tenants. We build in-law suites at this tier to function as real homes, not afterthoughts.
Adding significant square footage or a new structure will trigger a reassessment. The increase is proportional to the value added, and that added value is real, which is both the point and the trade-off. ADU-equipped properties in the area are cited as commanding a meaningful resale premium, and rental income from a one-bedroom unit can offset carrying costs substantially over time. The tax increase is a legitimate ongoing operating cost to build into your financial picture. We’d rather you know that going in than discover it on your next assessment notice. Transparent conversations about the full picture, construction scope, permitting, taxes, rental dynamics, are just how we work.
It starts with a site visit and an honest conversation about what your lot, your home’s systems, and your goals actually support, before anyone talks about drawings or timelines. From there, design development captures the layout and details that matter most to your family: the entry placement, the kitchen configuration, the accessibility features that make the space work for whoever’s moving in. Permitting runs concurrently with HOA review where applicable, and construction follows once both approvals are in hand. The whole sequence, design, permitting, build, runs nine to eighteen months for a full ADU or addition. It feels long until you’re sitting on that back porch on the first warm evening of the year with your parent in the unit next door, and then it feels like exactly the right amount of time.

Start The Conversation

Start Something New
for the Family You're Building Around

When your Commerce City home still fits your heart but not your household, an addition or ADU can change everything. A private space for a parent. Room for an adult child coming back. Or a self-contained unit that earns real rental income every month. Christie’s Design/Build Remodeling walks you through Commerce City’s brand-new ADU permitting process, from HOA review to plan check, so you’re never guessing what comes next. This is your home. Let’s make it work harder for everyone in it.
Start Planning Your Project
(303) 833-4715

Our Other Remodeling Services

Kitchen
Remodeling

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Basement
Finishing

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Whole-Home
Remodeling

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Bathroom
Renovation

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Deck
Construction

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Outdoor
Living Spaces

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From The Blog

What to Know Before You
Build Your First ADU

Planning an addition or ADU in Commerce City means navigating a process that most homeowners here are figuring out for the very first time. Our blog breaks down the dual HOA-and-city approval track, design decisions, permit timelines, and everything else that helps your new space feel worth every step.