Home Remodeling Boulder CO

GJ Koeppen Construction LLC

About business

Home Remodeling Boulder CO

Whatever part of your home requires renovations, you can trust us to help you. We have been working on home additions in Boulder, CO for years. Call us on 720-378-7660 for more details.

Services

Services

Service 01Basement Finishing
Service 02Before & After
Service 03Design And Construction
Service 04Dining Room
Service 05Outdoor Living
Service 06Partition Wall
Service 07Additions Services
Service 08Basement Finishing
Service 09Bathrooms Additions
Service 10Before & After
Service 11Design And Construction
Service 12Dining Room
Service 13Free Estimates
Service 14Outdoor Living
Service 15Partition Wall
Service 16Remodeled Kitchen
Attributes

Additional details

Offers Online Estimates
Onsite Services Provided
Profile

Business profile

Secondary categories
Home builder · Kitchen remodeler · General contractor
City
Longmont, CO
Country
USA
Postal code
80503
Company details

Business facts

2000Established
26Years in Business
How to reach us

Contact details

Address
7845 Lookout Road, Longmont, CO, 80503, USA
Social
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Reviews

Business rating and reviews

5Based on 14 reviews
5 star100%
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Natalie Hilsenbeck
October 2, 2026

After researching several companies and bids, we're glad we chose Koeppen Construction for our basement refinish project. Graham Koeppen personally came to our home several times to evaluate the space and worked with us planning the project, which also included installing a bathroom and plumbing and removing a support pole in the middle of the room in favor of a structurally sound support beam to open up space . Nikki was immensely helpful in guiding us regarding project selections and meeting deadlines. Joe the project manager was very helpful in day to day planning/logistics and problem-solving. Shout out to Forrest for an outstanding work ethic and excellent craftsmanship. Our basement space went from a drab, dusty storage area to an enjoyable livable space and has been a great addition to our home. We would hire the again for any future needs and highly recommend.

Christian Bruun Madsen
July 17, 2026

We used Koeppen Construction for a roughly 3-month remodel of our entire first level — kitchen, powder room, fireplace, flooring, stairs, and more — and highly recommend them. The design phase made all the difference. Graham was incredibly helpful walking us through options. We struggled most with the kitchen layout, and he came up with the idea of adjusting window to give us more cabinet wallspace — a great trade-off of real value added for low additional cost. They were thorough and careful upfront, so even though the project involved removing a wall and a large drywall feature, there were no surprises. Execution was super smooth. We got regular updates throughout, and I can't speak highly enough of their carpenter — great ownership of the work and extremely detail-oriented. Despite the scope, they kept the house clean and livable the entire time while we lived in it. They were clear about what would happen when, and efficient with the few subcontractors needed, so we always felt comfortable having people in the house. The result is beautiful — quartzite countertops, new windows, new floors and railings — and the whole process was as painless as a major remodel can be. I will use them again in a heartbeat for future projects.

Lily Hooper
April 22, 2026

Good people, great work. Koeppen Construction is the kind of company you actually enjoy working with. Everyone on the team is professional, easy to communicate with, and genuinely cares about doing the job right. They specialize in basements and ADUs, which are the kinds of projects that can really transform how you use your home. The craftsmanship they bring to every job is hard to beat. If you’ve been thinking about finishing that basement or adding an ADU, these are the people to call.

Haylee Brauer
April 21, 2026

Koeppen Construction is the kind of company that’s genuinely hard to find these days. Every person on their team operates with honesty and integrity, and it’s clearly a core part of who they are, not just something they say. They specialize in kitchen remodeling and bathroom renovations, and the quality of their work speaks for itself. Whether it’s a full kitchen transformation or a bathroom refresh, they bring craftsmanship and attention to detail to every project. If you’re looking for a remodeling company you can actually trust, one where the whole team shows up with professionalism and does right by their customers, Koeppen Construction is absolutely worth a call.

Nancy Ehrenreich
January 21, 2026

I’m happy to write this review of work recently done by Koeppen Construction at my home. I had asked the company to convert a window in my living room into a bay window – a far more complex project than I’d realized. But the project details turned out just as I’d wanted them to be, the woodwork was excellent (confirmed to me by friends who know more than I do about such things), and the project ran no more than a reasonable amount of time past schedule (especially given that we were doing it in the winter). Graham Koeppen and his crew were very patient with my frequent questions (I found it fascinating to watch the project take form), and I couldn’t be happier with the result. Thanks, Graham, Joe, Dexter and all!

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Find GJ Koeppen Construction LLC

7845 Lookout Road, Longmont, CO, 80503, USA

Need to know

Frequently asked questions

GJ Koeppen Construction LLC is listed under Construction and Remodeling. The About and Services sections on this page describe the business.

Opening hours have not been published yet. Please contact the business directly to confirm availability.

Call +1 (720) 378-7660, or use the email and website links in the Contact details panel.

The business is located at 7845 Lookout Road, Longmont, CO, 80503, USA. Use the map on this page for directions.

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