J ALLEN  CONSTRUCTION COMPANY: CUSTOM HOME BUILDERS IN FORT COLLINS

  • Custom Home Builds
  • Home Remodels
  • Home Maintenance
  • Home Additions

Established in 1998 - Fully Licensed and Insured - Detail-Oriented

Serving Berthoud, Johnstown, Fort Collins, Loveland, Windsor, or surrounding Northern Colorado areas

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Get the Home of Your Dreams

Are you looking for a custom home builder? You can create the perfect home with help from J. Allen Construction Company. Our custom construction meets your needs, and our detail-oriented team handles everything.


If you're interested in quality, just look at the gallery below to see examples of our work. Fill out the online form to work with a dependable home maintenance service company in northern Colorado and beyond.

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Custom Home Construction Contractors

When it comes to your home, quality matters. That's why you need a home contractor you can trust for building, renovations, and maintenance. At J. Allen Construction Company, we provide quality, custom construction services for your home.


You don't need to worry about anything when you hire us. Your investment with us is protected because we're fully licensed and insured. Contact us if you need a home maintenance company in Northern Colorado.

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Local and Family-Owned Since 1998

There are other construction crews in the area, but we do things the right way at J. Allen Construction Company. Our owner has 40 years of experience with home maintenance companies in Northern Colorado, Southern Wyoming and surrounding areas. He's involved with every job to ensure quality results every time.


We've used the same contractors for over 20 years, and we take pride in the quality of our work. There's a reason customers keep coming back to us!

Our Home Construction Services

Ready to Work With One of the Top Home Maintenance Companies in Northern Colorado, Southern Wyoming and surrounding areas?

For over 25 years, J. Allen Construction Company has been the home maintenance service company Northern Colorado residents have relied on for all their home project needs. From new builds to regular maintenance needs, our experts are prepared to work with you to achieve your vision. If you're looking to take the next step in your home renovations, don't hesitate to give our skilled crew a call today. We look forward to constructing the home of your dreams.

Here's what our satisfied customers are saying...

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Richard S

Great people working for you!!!

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Marvin J

We used J Allen for a complete kitchen and master bath remodel and was extremely pleased with the finished products. 

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By Marilyn Allen February 4, 2026
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By Marilyn Allen January 12, 2026
On September 22, 2025 , the Larimer County Board of County Commissioners adopted an updated set of building codes and local amendments that will apply to permits initiated on or after January 1, 2026 . These updates replace the County’s 2021 code editions effective that same date. At J Allen Construction Company , we’ve reviewed the adoption resolution and the County’s published guidance so homeowners, designers, and builders can understand what is changing and how it may affect planning, permitting, and project scope as 2026 approaches. Note, this blog is for informational purposes only; your project is unique and you may need to speak with the Colorado Energy Office for specifics about your case. What Has Changed: The 2024 I-Codes Become the Baseline (Starting January 1, 2026) Larimer County is adopting the 2024 editions of the core International Code Council “I-Codes” (with local amendments), effective January 1, 2026 , and repealing the previously adopted 2021 editions effective the same day. The adopted 2024 code set includes: 2024 International Building Code (IBC) 2024 International Residential Code (IRC) 2024 International Energy Conservation Code (IECC) 2024 International Existing Building Code (IEBC) 2024 International Mechanical Code (IMC) 2024 International Plumbing Code (IPC) 2024 International Fuel Gas Code (IFGC) 2024 International Property Maintenance Code (IPMC) 2024 International Swimming Pool and Spa Code (ISPSC) The County is also continuing to reference the 2023 National Electrical Code (NEC) in its published list of codes for 2026 permits. Why This Matters for Northern Colorado Homeowners and Builders 1) A newer code cycle is being adopted, but the resolution does not list every technical change Larimer County’s resolution explains the “I-Codes” are updated on a three-year cycle and are intended to reflect the most current building science and consensus process. What it does not do is itemize every requirement that changed between 2021 and 2024. So the safest way to think about this is: the baseline rulebook is updating , and depending on your project, you may see differences in plan review expectations, documentation, and prescriptive requirements compared to the 2021 editions. 2) Colorado’s Electric Ready and Solar Ready Code is included (and it is a state-required adoption) Larimer County’s adoption package includes the Colorado Electric Ready and Solar Ready Code , and the resolution notes this is a state-produced code that local governments must adopt when adopting other building codes. What homeowners should take from that is simple: many new builds (and some major projects) may need to be designed with “future readiness” in mind , even if you are not installing solar or fully electrifying on day one. Exactly what that means for your plans depends on the building type and the specific provisions Larimer is enforcing through its adopted amendments and permitting workflows . 3) Larimer County is adopting the 2025 Colorado Wildfire Resiliency Code (not a 2024 edition) This is a key detail. Larimer County’s public Building Codes page identifies this as the “ 2025 Wildfire Resiliency Code ” with Larimer County amendments, effective January 1, 2026 , and adopted on September 22, 2025 . So while the I-Code suite is the 2024 editions, the wildfire standard being adopted alongside them is explicitly the 2025 Wildfire Resiliency Code document. Wildfire Resiliency: What Homeowners Should Understand (And Where People Get This Wrong) A common misconception is that wildfire code requirements “only apply to brand-new homes.” The Larimer-adopted Wildfire Resiliency Code includes provisions that can apply to existing buildings when specific thresholds are met . For example, it states: Roof coverings: if a roof covering is replaced or if 25% or more of the roof surface area is replaced, the code can require the entire roof covering to be replaced to the new-construction standard (with noted exceptions). Exterior walls: if 25% or more of the total exterior wall surface area is replaced (or if the work effectively replaces the exterior wall material), the code can require the entire exterior wall surface area and certain near-structure zone conditions to comply (with noted exceptions). It also includes language clarifying that provisions that specifically apply to existing conditions can be retroactive. How This Affects Remodels and Additions If you’re planning a remodel or addition , the key trigger is the County’s timing language: the adopted 2024 codes apply to permits initiated on or after January 1, 2026 . In practice, that means: Energy requirements for new or altered conditioned space will be reviewed under the 2024 IECC framework for 2026 permits. Life safety and building requirements for the new work will be reviewed under the applicable 2024 code(s), depending on whether the project is residential or commercial and how it is classified. The 2024 International Existing Building Code (IEBC) continues to be part of Larimer County’s adopted code framework and provides updated pathways for repairs, alterations, changes of occupancy, and additions in existing buildings. If the property is in a designated WUI area , wildfire-resiliency provisions may become relevant for certain additions and exterior alterations, including the “25% roof” and “25% exterior wall” triggers described above. Final Thoughts  Larimer County’s updated code adoption is a meaningful shift because it updates the baseline standards used for plan review starting January 1, 2026 , and it folds in Colorado’s Electric/Solar Ready requirements and the 2025 Wildfire Resiliency Code (with county amendments). For project-specific guidance, consult the Larimer County Building Division resources and your design professionals so you can align your plans with the standards that will govern your permit review in 2026. Of course, you can always hire us, and we’ll just handle all this for you! Get in touch with us for your next Northern Colorado addition, renovation, or home maintenance project.
By Alex Wells December 3, 2025
When a Permit Is Definitely Required for Your Addition  When you’re adding onto your home in Fort Collins, the city treats that work much like new construction. On the City’s Fast Track Permits page, “ Additions ” are listed under New Construction alongside new houses, sheds, and garages , which means they’re clearly in the permit-required camp. The residential submittal guide also spells out permit requirements for “New Single Detached Family Homes, Duplexes, Townhomes, and Additions,” with a dedicated checklist for those projects. In practical terms, you should expect to need a building permit if you’re planning to: Expand your home’s footprint with a bump-out or new wing Add a second story or pop-top Build an attached garage or finished space over a garage Do structural work (foundation, load-bearing walls, roof framing) tied to the addition Extra Layers: Zoning, Development Review, and Floodplains On some properties, the permit is only part of the story. Zoning & Development Review For certain projects, Fort Collins notes that a development review process may be required before you even submit for a building permit , especially when you’re changing how the site is used or adding more intense development. That’s where setbacks, lot coverage, height, and allowed uses get checked against the zoning rules, so you don’t design an addition the City can’t approve. Floodplains If your home sits in a mapped floodplain, the City requires a Floodplain Use Permit for any work done in the floodplain , including additions. Fort Collins also requires new residential structures and additions in the 100-year floodplain to be elevated above the mapped flood level , with specific freeboard requirements. What Happens If You Skip the Permit? Starting an addition without a permit isn’t just “bending the rules” a little. In Larimer County, if you begin construction without a required building permit, the building department can issue a Stop Work Order , require you to halt all work, and charge double the normal permit fee to legalize what’s already been done. Larimer County They also warn that unpermitted work might not meet setback rules, which can force you to move or even remove the structure, and you may be asked to open finished walls or ceilings so inspectors can see what’s inside. Bringing It All Together: Start With Good Information When you zoom out, the pattern is pretty simple: if your home is inside Fort Collins city limits, the City’s Building and Zoning Division is going to look at your addition the same way it looks at any new building or alteration, with plan review and inspections to make sure the work meets local code. If you’re just outside town, Larimer County’s building division fills that role for unincorporated areas. In both places, permits and scheduled inspections are what turn a set of drawings into a safe, legal space you can actually use.
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