Additions and ADUs in Louisville, CO

A Home That Finally Has Room for Everyone You Love

Why Louisville Homeowners Choose Christie's

Because the Home You've Chosen to Stay In
Should Finally Have the Space to Prove It

For more than 25 years, Christie’s has helped Louisville homeowners figure out how to stay in the city they’ve deliberately chosen, and build the space that makes staying make sense. A basement that’s been sitting unfinished for fifteen years, finally converted into a real in-law suite with a private entrance, a full kitchen, and a no-step shower your parent can actually use. A detached ADU in the backyard that works for mom today and becomes a long-term rental in five years when her situation changes.

At Christie’s Design/Build Remodeling, we start by being honest about what your 1980s ranch can actually carry, the electrical panel, the existing plumbing, the basement ceiling height, because in Louisville, those details surface at the permit stage whether you’ve planned for them or not. From Old Town’s historic overlay to newer subdivisions near McCaslin and the established neighborhoods tucked between Highway 42 and the open space, we plan additions and ADUs around your real home, your real lot, and the next twenty years of your life in it.

In Business

25+ Years

Helping Louisville homeowners turn aging basements, underused garages, and modest ranch footprints into private, fully permitted living space for the people they're building the next chapter around.

Our Model

One Team

Your Louisville addition or ADU stays with one coordinated team from feasibility and design through permitting, construction, and the final walkthrough.

Where We Work

Louisville, CO

Serving homeowners throughout Old Town Louisville, Harper Lake, Coal Creek Ranch, Centennial Valley, and established neighborhoods across Louisville.

Peace Of Mind

5-Year Warranty

Your new Louisville addition or ADU stays backed after construction wraps, so you can settle into the space with real peace of mind.

What Makes Additions & ADUs Different In Louisville

The Space You Build
Should Feel Like It Always Lived Here

Adding onto a Louisville home means you’re starting with real, specific conditions, a 1980s ranch that’s served your family well but never quite had enough room, a basement with ceiling heights that may or may not clear habitable space minimums, and a permit process that’s actually more predictable than most neighboring cities thanks to Louisville’s May 2024 ADU ordinance. What that clarity doesn’t change is the honest work of assessing your electrical panel, your HVAC, and your plumbing before any design decisions get made, because those systems surface at the permit stage regardless. At Christie’s Design Build, we put the full picture on the table early, lot setbacks, Old Town overlay requirements if they apply, utility feasibility, and construction contingency, so the number you’re working toward is the real one. The goal is an addition or ADU in Louisville, CO that works for your parent today and converts for someone else five years from now without feeling like it was ever an afterthought.

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Louisville Ranches Have Real Character

Louisville’s 1970s–1990s ranches and split-levels each open up different paths for added space, basement conversions, garage ADUs, or pop-tops. We study your structure and lot first so the right direction is clear before design begins.

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Louisville's Ranch Bones Set the Starting Point

Louisville’s 1970s–1990s ranches carry their own structural realities, rooflines, and basement configurations. We assess those conditions first so the addition ties in naturally and holds up as one home.

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Louisville's 1980s Systems Need Honest Review

Louisville’s older ranches frequently have undersized electrical panels and original plumbing that wasn’t routed with a second unit in mind. Surfacing those realities during planning keeps the budget honest from day one.

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Front Range Weather Demands Thoughtful Material Choices

Louisville’s elevation brings hard freeze-thaw cycles, intense sun, and dry winters that put real pressure on exterior materials and insulation, especially where new construction meets a 1980s wall. We spec those details so the added space stays comfortable and holds up across every season.

Louisville, CO Neighborhoods

More Room Without Leaving
the Louisville You've Chosen to Stay In

Louisville is filled with 1970s and 1980s ranches that families have owned long enough to outgrow, homes on modest lots where a parent’s arrival, a returning adult child, or a third kid suddenly makes the floor plan feel impossible. Some households need a genuinely private in-law suite before the situation becomes urgent, with its own entrance and a real kitchen, not a converted spare bedroom. Others have a backyard or an older detached garage that could finally become something useful. Sometimes it’s the primary suite or the main living area that simply never fit how the family actually lives, and everyone has been quietly making it work for years. What makes each project here in Louisville specific is the home itself, older mechanicals, modest lot dimensions, setbacks, and utility routing that all shape what’s actually buildable before design begins. Louisville’s May 2024 ADU ordinance removed the public hearing requirement, which means a qualifying lot can move toward permit on a defined, knowable track. We start every conversation by asking what this home needs to carry your family through the next twenty years.

Coal Creek Ranch

When a Newer Home Still Has Room for the Life Ahead

Coal Creek Ranch homes were built with intention, mountain views out back, trails winding through open space, a neighborhood families deliberately chose and tend to stay in. But even a well-designed newer home can leave you short on the specific configuration life eventually asks for: a fully private suite for a parent who needs their own kitchen and front door, or a dedicated ADU that works for family now and earns rental income later. HOA architectural review is part of the process here, and we come in already familiar with how master and sub-association approvals work, so the design clears that process rather than stalls in it. What gets added looks like it was always meant to be here.

Cherrywood

Build What's Missing Without Changing What the Street Fell in Love With

Homes in Cherrywood already have the bones families come back to, established lots, mature trees that take decades to grow, and a ten-minute walk to Old Town that most Louisville neighborhoods can’t match. What’s often still missing is a purpose-built space: a fully private in-law suite where your parent has their own entrance and kitchen, a primary suite that finally matches how you actually live, or a dedicated home office that isn’t a corner of the guest room. We design every addition around Cherrywood’s canopy, character, and existing architecture, so what you add reads like it was always there, not like something that arrived later and never quite settled in.

Old Town Louisville

When a Beloved Old Home Finally Has Room for Everyone

Old Town’s mining cottages and period homes carry a quiet character that’s hard to replicate, which is exactly why the families who live here aren’t looking to leave. But a compact floor plan built in 1910 or 1975 wasn’t designed for a parent who needs nearby privacy or an adult child who needs a real kitchen of their own. An addition or ADU here means reading the home’s original construction methods and materials carefully, then designing something that earns its place on the block rather than interrupting it. We coordinate early with the City on any applicable design considerations so the finished space feels rooted in Old Town’s character, not added onto it as an afterthought.

Centennial Heights

Give the Home You're Staying In the Space It's Always Needed

Centennial Heights homes don’t come to market often, and the families who live here tend to stay, which means when a parent’s health shifts or an adult child needs a real place to land, moving isn’t the answer. The ranch and two-story homes on these spacious lots have real potential for a well-designed addition or ADU, whether that’s a fully private in-law suite with its own entrance or an expanded primary wing that finally fits how your household actually lives. We work with the chalet-style rooflines, the prominent decks, and the mature lot character that define this neighborhood so what gets built reads as intentional, part of the original home, not an afterthought behind it.

Rock Creek Ranch

Make the Home That Already Fits You Work for the Long Run

Rock Creek Ranch homeowners didn’t land here by accident, the gated setting, the modern construction, the finish level all lined up with exactly what you wanted. But even a newer, well-built home stops working when a parent needs genuine privacy, an adult child comes back, or the household simply shifts in ways the original floor plan never anticipated. Because these homes carry a deliberate, contemporary character, any addition or ADU has to hold that same standard. We coordinate carefully with the community’s access and architectural review process, then match materials, rooflines, and proportions so what we add feels like it was always part of the plan.

Our Louisville Additions & ADU Process

From the First Conversation to the Day It Feels Like Home

Adding an addition or ADU in Louisville brings questions that are specific to this city and the home already standing on your lot, the 1980s electrical panel that needs upgrading before a secondary unit can be permitted, the basement ceiling that may fall just short of habitable height, the Old Town historic overlay that adds a distinct layer of review for properties in that district. A ranch near Old Town Louisville calls for a very different conversation than a newer home in a planned subdivision. Our process moves each project through site evaluation, design, permitting, utility coordination, construction, and final walkthrough with one team keeping the whole picture clear from start to finish.

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Site & Structure Review

Every Louisville addition or ADU starts with an honest look at what your property can actually support. We walk the lot, confirm setbacks, assess the existing structure, and look at how your household moves through the home today. On Louisville’s 1970s and 1980s ranches, that also means evaluating foundation conditions, load-bearing walls, and the condition of older mechanical systems before design decisions get made. That groundwork shapes everything that follows.

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Goals & Design Direction

Before plans take shape, we talk through who this space is really for and what it needs to do over the next ten to twenty years, not just right now. In Louisville, that often means a basement or detached garage conversion that works for your parent today with no-step access and wider doorways, but converts naturally to a rental or adult-child unit when the situation changes. We think through how the new space connects to your existing home so every decision carries a purpose.

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Detailed Project Planning

Once we know where you’re headed, we translate your goals into a buildable plan grounded in what your Louisville property can actually support. That means addressing aging electrical panels, original HVAC, unrouted plumbing, and the specific requirements Louisville’s ADU ordinance sets around egress, ceiling height, and energy code before a permit gets filed. Working through those realities now is what keeps your project honest and your timeline from unraveling mid-construction.

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Permits & Trade Coordination

Before construction begins, we coordinate Louisville’s permit filings, review timelines, utility-connection sequencing, and trade scheduling for your specific project. We account for the permit fee range, energy code requirements, and the order each specialty trade needs to arrive, especially on basement conversions and garage ADUs where electrical, plumbing, and HVAC work must land in the right sequence. That organization gives you one clear point of contact instead of chasing answers from multiple directions.

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Construction & Communication

With Louisville’s permits in place, your new space starts taking real shape. Framing, insulation, mechanical upgrades, drywall, flooring, cabinetry, and finishes all move forward under one coordinated team, whether we’re finishing a basement into a fully accessible in-law suite, converting a detached garage into a permitted ADU, or adding a second story to a single-story ranch. You stay informed throughout while we protect the quality and connection between the new space and the home you’re staying in.

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Final Review & Completion

As construction wraps up, we walk the completed addition or ADU with you and go through every detail together, finishes, fixtures, accessibility features, and how the new space connects to the rest of your Louisville home. We close out any remaining items and make sure nothing feels out of place or disconnected from what was already there. The goal is a finished space your parent, your adult child, or your future tenant can move into and immediately feel settled.

Our Louisville Additions & ADU Process

From the First Conversation to the Day It Feels Like Home

Adding an addition or ADU in Louisville brings questions that are specific to this city and the home already standing on your lot, the 1980s electrical panel that needs upgrading before a secondary unit can be permitted, the basement ceiling that may fall just short of habitable height, the Old Town historic overlay that adds a distinct layer of review for properties in that district. A ranch near Old Town Louisville calls for a very different conversation than a newer home in a planned subdivision. Our process moves each project through site evaluation, design, permitting, utility coordination, construction, and final walkthrough with one team keeping the whole picture clear from start to finish.

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Site & Structure Review

Every Louisville addition or ADU starts with an honest look at what your property can actually support. We walk the lot, confirm setbacks, assess the existing structure, and look at how your household moves through the home today. On Louisville’s 1970s and 1980s ranches, that also means evaluating foundation conditions, load-bearing walls, and the condition of older mechanical systems before design decisions get made. That groundwork shapes everything that follows.

.02

Goals & Design Direction

Before plans take shape, we talk through who this space is really for and what it needs to do over the next ten to twenty years, not just right now. In Louisville, that often means a basement or detached garage conversion that works for your parent today with no-step access and wider doorways, but converts naturally to a rental or adult-child unit when the situation changes. We think through how the new space connects to your existing home so every decision carries a purpose.

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Detailed Project Planning

Once we know where you’re headed, we translate your goals into a buildable plan grounded in what your Louisville property can actually support. That means addressing aging electrical panels, original HVAC, unrouted plumbing, and the specific requirements Louisville’s ADU ordinance sets around egress, ceiling height, and energy code before a permit gets filed. Working through those realities now is what keeps your project honest and your timeline from unraveling mid-construction.

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Permits & Trade Coordination

Before construction begins, we coordinate Louisville’s permit filings, review timelines, utility-connection sequencing, and trade scheduling for your specific project. We account for the permit fee range, energy code requirements, and the order each specialty trade needs to arrive, especially on basement conversions and garage ADUs where electrical, plumbing, and HVAC work must land in the right sequence. That organization gives you one clear point of contact instead of chasing answers from multiple directions.

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Construction & Communication

With Louisville’s permits in place, your new space starts taking real shape. Framing, insulation, mechanical upgrades, drywall, flooring, cabinetry, and finishes all move forward under one coordinated team, whether we’re finishing a basement into a fully accessible in-law suite, converting a detached garage into a permitted ADU, or adding a second story to a single-story ranch. You stay informed throughout while we protect the quality and connection between the new space and the home you’re staying in.

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Final Review & Completion

As construction wraps up, we walk the completed addition or ADU with you and go through every detail together, finishes, fixtures, accessibility features, and how the new space connects to the rest of your Louisville home. We close out any remaining items and make sure nothing feels out of place or disconnected from what was already there. The goal is a finished space your parent, your adult child, or your future tenant can move into and immediately feel settled.

What Louisville Homeowners Want From Their Addition or ADU

More Room for the
Next Twenty Years

Addition and ADU projects in Louisville are almost always about something more specific than extra space, they’re about a parent who needs to be close but deserves a real front door and a bathroom that works for aging knees, or an adult child who needs somewhere to land while the family figures out the next chapter together. Louisville’s 1970s–1990s ranches sit on modest lots with older mechanicals, which means the honest conversation about what a basement conversion or garage ADU actually involves, electrical panels, plumbing routing, egress windows, energy code, has to happen early, before anyone falls in love with a floor plan that the existing structure can’t support. Louisville’s May 2024 ADU ordinance removed the public hearing requirement, so the regulatory path is more knowable here than in most Front Range cities, and that predictability matters when you’re planning around a parent’s timeline or a lease ending. What Louisville homeowners want most is a space built for the next twenty years, not just the next eighteen months.

Space for Parents, Everyone

Space Built to Stay

In Louisville's established neighborhoods like Old Town and the South Boulder Road corridor, most homes were built for households a fraction of today's size, and without the multigenerational configurations families now need. A thoughtful addition or ADU can create a private suite for aging parents, give an adult child genuine independence, or open a main living area that's felt too tight for years.

Plans That Flex Over Time

Room for the Long Haul

Many Louisville ranches are still carrying the same floor plan they had in 1983, and it shows. Reconnecting old and new space thoughtfully, with real flow and no awkward transitions, is where these projects start feeling like home again.

Organized Systems, Finally

Their Own Key, Finally

Louisville's modest lot sizes mean a well-planned addition has to work harder than just adding square footage. Built-in storage, a mudroom drop zone, and smart laundry placement make the finished space feel calmer and genuinely easier to live in.

Close By, Genuinely Independent

Near, Without Feeling Crowded

For homeowners near Old Town Louisville and the Centennial neighborhood, a permitted ADU or in-law suite can make multigenerational living feel genuinely sustainable rather than improvised. A private entrance, full kitchen, and no-step bathroom change everything about how the whole arrangement feels, for everyone involved.

Matched to Louisville Homes

Built for Louisville's Real Life

Louisville additions have to hold up against freeze-thaw cycles, hail seasons, and the energy code requirements that come with Colorado's altitude, none of which are optional at the permit stage. Exterior cladding, insulated envelope details, and interior finishes chosen for real Front Range conditions keep the new space performing exactly the way it should, year after year.

What To Consider When Building An Addition or ADU In Louisville

Make Room for the Life
Louisville Already Gave You

An addition or ADU can completely change how a Louisville home holds the people who need to be close, but the best projects start well before anyone opens a floor plan. A 1970s ranch with an older detached garage brings real questions about electrical capacity, plumbing routes, and setbacks that a newer home on the city’s western edge simply doesn’t, and if you’re in Old Town, the historic overlay adds its own layer before design can move forward. Knowing who the space is truly for, what their day needs to feel like inside it, and what your specific lot and structure can honestly support is where the right project begins.

Who is this space really for, and will that answer change in five years?

It’s worth sitting with this one honestly. A space built for your mom today needs to work for her now, no-step shower, wider doorways, a kitchen she can actually use, but it also needs to make sense as a rental or an adult-child suite down the road. Louisville homeowners who think through the full arc of who uses the space, and when, end up with a unit that earns its investment for the long haul instead of one that needs retrofitting the moment life shifts again.
That unfinished basement or older detached garage might look like the obvious starting point, but what’s underneath matters just as much as what’s above it. Louisville’s 1970s and 1980s ranches frequently carry undersized electrical panels, original HVAC, and plumbing that was never routed with a second unit in mind. Being honest early about what your existing structure can support, and what it will need before permits are pulled, is how you build a real budget instead of a wishful one.
Most homeowners picture the framing and the finish work. The months before that, feasibility checks, design, permit review, are where Louisville projects live or stall. A complex ADU or addition realistically runs 9–18 months from first conversation to move-in, and the permit fees alone ($6,540–$9,596 depending on scope) are a line item worth knowing upfront. If there’s a date driving your project, a parent moving in, a lease ending, building your timeline backward from that moment is one of the most useful things you can do before design begins.
If you’re in Old Town Louisville, the historic district overlay means material choices, roofline massing, and façade treatment all go through a review process that doesn’t apply in the city’s newer subdivisions. If you’re in a planned community with an HOA, Colorado law means they can’t block your ADU, but they can shape how it looks. And no matter where you are in Louisville, your lot setbacks and existing structure placement will determine what’s possible before any design conversation starts. Knowing your specific layer of review early saves everyone a lot of rework.

Our Reviews

Trusted by Louisville Homeowners
With the Spaces Their Families Come Home To

Choosing a team for an addition or ADU in Louisville means trusting them with the hours that matter most, the evening quiet after dinner, the moment your parent steps through their own door for the first time, the year this home finally fits your life. Our reviews reflect the honesty, steadiness, and genuine care Christie’s brings to every Louisville project from the very first conversation through the final walkthrough.

Areas We Service Across Louisville

Your Louisville Home,
Built for the Long Haul

Across Louisville, homeowners are sitting in 1980s ranches they deliberately chose, good bones, great neighbors, schools worth staying for, and realizing the floor plan simply doesn’t fit the family it holds anymore, whether that’s a parent who needs their own door or a household that’s just run out of room to breathe. From the older lots in Old Town with their detached garages and historic overlay considerations, to the planned subdivisions along McCaslin where secondary suites never made it into the original build, every property brings its own starting point. Christie’s works through Louisville’s real specifics, ADU setbacks, aging mechanical systems, permit timelines, Old Town’s design review, and builds space that feels like it was always part of the house.

Other Areas We Service

Broomfield County

Louisville Addition & ADU Frequently Asked Questions

The Questions Behind
Staying in Louisville and Making It Work

Adding onto a home you already love in Louisville brings its own specific set of questions, especially when you’re working with a 1980s ranch, a modest lot, and the real possibility that aging mechanical systems will surface the moment permits get pulled. The answers here depend on your home’s structure, lot dimensions, the historic district overlay if you’re in Old Town, and where your utilities currently sit relative to a new unit. Louisville’s ADU process is more predictable than most, but there are still real permit requirements, timeline realities, and cost factors most homeowners don’t fully see until someone lays them out. These are the questions we hear most from Louisville families who are ready to make the home work for the next twenty years.

Still Have Questions?
We're Here To Help.

Does Louisville's May 2024 ADU ordinance actually make it easier to build an ADU on my property?

It genuinely does, and in a meaningful way. Before the state law took effect, some Colorado cities required discretionary approvals, public hearings, or neighborhood sign-off that could slow or kill a project before it ever got to design. Louisville’s current process doesn’t require any of that. If your single-family lot meets the basic requirements, you move from feasibility to permit application on a defined track. No public hearing, no variance request, no waiting to see how a board votes. That predictability is real, and it matters for planning your timeline with confidence.
Homes from that era were built with systems sized for one household doing one thing, and they weren’t thinking about a second kitchen, a separate electrical meter, or an HVAC zone running independently in the back of the lot. When you start pulling permits for an ADU or an in-law suite conversion, undersized electrical panels, original HVAC equipment, and unrouted plumbing all tend to surface as required upgrades. That doesn’t mean the project doesn’t make sense, it just means those system updates need to be in your budget from conversation one, not discovered mid-construction. We flag these early so there are no surprises.
That’s one of the most common things we hear from Louisville families, and honestly it’s the smartest way to think about the investment. A well-designed unit, with a no-step shower, wider doorways, lever hardware, and a private entrance, works genuinely well for a parent with limited mobility today. Those same features are exactly what quality long-term tenants look for tomorrow. Full kitchen, in-unit laundry, dedicated outdoor space: those aren’t extras, they’re what makes the unit function across its whole life. We design for the 15-year picture, not just the first use.
It does add a layer, yes. Old Town’s historic district overlay means your ADU or addition isn’t just reviewed for setbacks and square footage, it’s also evaluated on material matching, massing compatibility, and how the new structure reads from the street. A detached ADU that looks like an afterthought behind a Victorian-era home won’t sail through. The good news is that these requirements are knowable up front. We do the feasibility work on your specific lot and overlay conditions before any design begins, so you’re not redesigning after you’ve already fallen in love with a plan.
Under Colorado state law, your HOA cannot prohibit you from building an ADU on your property. That’s a hard protection. What they can do is impose design requirements, specific exterior materials, roofline treatments, things like that, and those can affect scope and cost if you don’t know about them before design begins. We’ve worked through HOA design requirements alongside city permitting in Louisville’s planned subdivisions, and the key is addressing both tracks early in the process rather than letting one surprise the other mid-project.
For a complex project, a detached ADU, a second-story addition, a fully permitted basement conversion, a realistic timeline runs nine to eighteen months from that first conversation to move-in day. That’s not padding; it accounts for design, permit review, and construction in sequence. Simpler scopes can move faster. The permit review window is one of the variables you can’t fully control, and Louisville’s planning department, like most smaller city offices, has a finite team. We’ll give you an honest project-specific range early, not a best-case scenario to get you started.
Those numbers usually reflect construction cost alone, and they often reflect lower-spec construction at that. What they leave out is design fees, permit fees (which in Louisville run into the several-thousand-dollar range depending on scope), utility connections, energy code compliance upgrades, and a construction contingency for the things that show up once walls open. When you add it all up on a custom detached ADU with a full kitchen, accessible bathroom, and exterior finishes that actually match the main house, the number is higher, and it should be. We’ll walk you through an itemized picture before you commit to scope, so you know exactly what you’re working with.
It seems simpler at first, and for good reason. The structure is already there. But a fully permitted, livable garage ADU in Louisville requires egress windows, insulation to current code, a full HVAC system, plumbing rough-in for a kitchen and bath, updated electrical, and exterior work to make the space read as intentional living space rather than a converted storage bay. For older detached garages especially, the structural bones often need reinforcing too. It’s a real path, and it can be the right one, but we want you to go in with a clear-eyed sense of what’s actually involved, not a garage-conversion sticker price that doesn’t reflect the finish line.

Start The Conversation

Room to Stay
in the Louisville Home You've Chosen

When your Louisville ranch still has everything you love about this city but not quite enough room for the life you’re actually living now, an addition or ADU can make staying the right call for the next twenty years. A real in-law suite with its own entrance, its own kitchen, real privacy. Space that works for your parent today and converts to rental income or an adult child’s landing pad when things shift. Christie’s Design/Build Remodeling handles the feasibility work, the permit complexity, and the aging mechanical systems that older Louisville homes bring to the table, so what gets built genuinely belongs here.

Our Other Remodeling Services

Kitchen
Remodeling

Basement
Finishing

Whole-Home
Remodeling

Bathroom
Renovation

Deck
Construction

Outdoor
Living Spaces

From The Blog

Your Louisville Ranch
Has Room for the People Who Need It

Planning an addition or ADU in Louisville, especially when you’re working with a 1980s ranch, aging mechanical systems, and a permit process most homeowners haven’t navigated before, brings up questions that deserve straight answers before you commit. Our blog covers the decisions honestly, from ADU regulations and all-in costs to what makes new space genuinely work for your family long term.