Koeppen Construction

Fall In Love
With Your Home Again!

Is your home tired, outdated, or just too small? With home prices through the roof and inventory low, trust Koeppen Construction with your dream and we will help you remember why you first fell in love with your home.

Premier Home Remodeling Contractor In Boulder & Longmont, CO

Koeppen Construction is a premier team of home remodeling contractors serving Longmont, CO, Boulder, CO, and the surrounding areas. Our expertise spans various areas, including kitchen remodeling, basement finishing, home additions, accessory dwelling units, garage additions, in-law suite additions, and basement remodeling.

Whether your home feels outdated or does not function for your family, Koeppen Construction is here to help. As trusted home remodel contractors, we breathe new life into your home, making it a place you once again love to be.
Kitchen Renovation Longmont CO

Update Your Cooking and Dining Area with Kitchen Remodeling

Our team is skilled at transforming kitchens into functional and beautiful spaces. We offer comprehensive kitchen remodeling services, from updating plumbing fixtures to installing new cabinetry and appliances. We work closely with you to create a kitchen that meets your unique needs and reflects your style.

Add Function with a Finished Basement

Basement finishing is one of our residential remodel specialties. We turn your basement into a functional space that meets your family’s needs and increases the value of your home. Whether you need a man cave, an entertainment area, or extra bedrooms, our expert team can deliver a basement remodel that exceeds your expectations.

Expand Your Living Space with Home Additions

We also excel in home additions. Whether you want to add a bedroom, create a luxurious master suite, or build a sunroom to enjoy the abundant Colorado sunshine, we are here for you.

Our home addition services also include the construction of accessory dwelling units. Often referred to as mother-in-law suite additions, backyard cottages, garage additions, or basement apartments, these additions enhance your living space, increase your home’s value, and provide the extra space you need for your growing family or changing lifestyle.

As the leading residential remodeling contractors near me, we are fully licensed and insured. We guarantee your satisfaction by ensuring excellent communication, value-driven pricing, and delivering a final product that aligns with your vision.

Contact Koeppen Construction today at (720) 378-7660 for all your home remodeling needs in Longmont, CO, and Boulder, CO.

Years In Business
years combined experience
Satisfied Clients

What We Offer

Basement Finishing Longmont CO

Basement Finishes

Growing family? Need a man cave? Finishing your basement is the most economical way to meet the needs of your family while increasing the value of your home.

Kitchen Remodeling Longmont CO

Kitchen Remodels

Need to increase your kitchen capacity for hospitality? Breath life back into the heart of your home with new cabinetry, updated plumbing fixtures, and appliances.

Home Additions Longmont CO


Pop the top, or blow out that wall to add a bedroom or create that master suite you’ve always dreamed of. Take advantage of Colorado’s 300 days of sunshine in a new sunroom!

Home Renovation Longmont CO

Major Renovations

Tired of the bright gold fixtures, tile countertops, and that wall blocking your view to the living room? Maximize your investment by updating multiple rooms at the same time.

Accessory Dwelling Units Longmont CO

Accessory Dwelling Units

Often called mother-in-law suites, backyard cottages, garage, or basement apartments, these areas add to your functional living space and increase the value of your home.


Calvin Coursey
Calvin Coursey
They do quality work in a short time will recommend to all looking for remodeling contractors...
Rick Mansfield
Rick Mansfield
We ended up accepting the bid of another contractor whose schedule better fit our need for a quick turnaround, so we can't speak to the overall renovation experience, but Graham impressed us with his professionalism throughout a somewhat complicated bid process. He asked incisive questions about what we wanted and suggested alternatives where appropriate during the initial consultation at the house. His bids were carefully itemized to facilitate comparison with other bids, and both his original bid and his update (when we changed what we requested) were fair. He was transparent about his schedule and didn't make promises he couldn't deliver. And he was patient as we agonized over our decision, and accepted with grace our final decision to go with another bid. I wouldn't hesitate to recommend Graham to others in need of contracting services.
Laura W
Laura W
We were HIGHLY impressed with GJ Koeppen from start to finish on a basement build-out to mother in-law apartment. Work was done on time, project came in on budget, their crew is friendly and professional, and the quality of the work is excellent. Any project will have a few minor snags; they responded and resolved those issues quickly and to our satisfaction. They stayed very communicative and transparent through all stages: from bid to administration/change orders (increased costs due to OUR changes/requests for preferred finishes) through actual work we were very impressed with all of their staff. We wouldn't hesitate to use them again on future projects, and have already recommended them to friends.
Harmony (HarHarHar)
Harmony (HarHarHar)

Meet Our Team

President & Estimator

Graham is the first person you’ll meet on the job. His seventeen plus years of experience in the construction industry qualify him to address all of your project needs. He is the solid foundation of the company.


Office Manager

Niki works with our marketing team and handles social media and communication within the community. She manages project purchasing, assists with clients and vendors, and handles office administrative duties.


Project Manager & Estimator

Joe handles the day to day scheduling of the workflow for our projects, coordinates our subcontractors, and is our basement specialist.



Mary handles company finances including client and vendor billing.


Lead Carpenter

With over 20 years in construction and remodeling, Kyle’s onsite experience is invaluable to your project’s success.


Quality & Integrity You Can Build On!