Seamless Home Additions in Denver & the Front Range
POP-TOPS AND FULL FOOTPRINT EXPANSIONS THAT FEEL LIKE THEY WERE ALWAYS PART OF THE HOUSE
Add the Space, Keep the Home
A home addition lets you stay in the neighborhood you love and get the space you need. We build pop-tops and full footprint expansions, from a primary suite addition to a second story that doubles your square footage. The work integrates with what's already there structurally, and the finish work makes the new space feel like it was always part of the house.
Most of our additions are for homeowners staying in their home long term. That changes how we approach the planning, the structural work, and the finish details. We want the addition to feel like it belongs, not like it was bolted on.
A Structured Approach to Complex Additions
Home additions are one of the most complex types of residential construction, requiring careful planning, coordination, and execution. Our team takes a structured approach to ensure every detail is addressed before construction begins, from structural considerations to tying into existing systems and finishes.
Throughout the project, we prioritize clear communication, detailed planning, and consistent oversight so there are no surprises along the way. You can expect a responsive team that understands the importance of timelines and quality craftsmanship.
Frequently Asked Questions About Home Additions
Curious about what to expect? Here are answers to some of the most common questions homeowners ask about home additions.
- How long does a home addition take?expand_more
- Construction typically runs 8 to 14 months, depending on the scope. Planning and design before construction can add a few additional months, especially if the project needs structural work, permits, or custom selections. We map out the full timeline before construction begins so you know what to expect.
- Is it better to build up or build out?expand_more
- It depends on your lot, zoning restrictions, and goals. Building up (second story) maximizes space without increasing footprint, while building out can be more straightforward structurally.
- Will the addition match my existing home?expand_more
- Yes. A well-designed addition should feel like it was always part of the home. We focus on blending materials, structure, and design details to create a seamless result.
- Can I live in my home during the addition?expand_more
- In many cases, yes. However, it depends on the scope and how the addition connects to your existing living space.
- Do you handle permits and structural planning?expand_more
- Yes. We help guide the planning process and coordinate the necessary steps to ensure your addition is built correctly and meets local requirements.
A Structured Approach Designed Around Your Project
Many homeowners choose to include these upgrades when investing in a home addition project:
Explore Recent Projects Built With Quality and Attention to Detail
Home Addition Cost Guide
Planning a remodel or build and want to understand real costs before you commit? Download our Remodeling Cost Guide to get clear expectations, avoid surprises, and make confident decisions from the start.
- Real project cost ranges for remodels, additions, and custom homes in the Denver and Front Range area
- Insight into what drives pricing so you can plan your investment with confidence
- Guidance to help you avoid costly mistakes and choose the right type of project for your goals
Where We Work
We work across the Denver metro and the Front Range, from whole-home renovations and additions to insurance restoration work that takes us throughout Colorado and into southern Wyoming. Wherever the project is, the standard is the same.
If you don't see your area listed, reach out. We may still be the right fit.
Our Service Area
- Denver
- Boulder
- Cherry Hills Village
- Cherry Creek
- Hilltop
- Washington Park
- Greenwood Village
- Castle Pines
- Castle Rock
- Genesee
- Littleton
- Applewood
- Arvada
- Evergreen
- Cherry Hills
- Golden
- Louisville
- Lone Tree
What Our Clients Say
"Cillessen have done several reconstruction and remodeling projects for us and have always done a superb job. We’ve worked with them for 5 years and have come to know some of the workers who have been there for years. We’ve seen them move up, get new positions and grow. They are true craftsmen and artisans. We recommend Cillessen highly."
John Schmaus
"Dylan and Kurt did a great job. Very professional job. The work looks great and it was done right. And got me those supplements from the insurance company. thanks guys"
Michael Bingham
"Excellent general contractor with top-quality workmanship. The team was punctual, reliable, and paid great attention to detail. They completed the project on time and kept me updated throughout the process. The final result exceeded my expectations. I’m very happy with the service and highly recommend them."
Ashley McKee
"I’ve had the opportunity to interact with Devon professionally and have consistently been impressed with his integrity, communication, and attention to detail. He runs a thoughtful, organized operation and clearly takes pride in doing things the right way. I wouldn’t hesitate to recommend Cillessen Construction Company to those looking for a quality contractor."
Ryan Koelling
"Devon at Cillessen is great to work with. I'm a local Realtor and I refer all my clients exterior needs to Cillessen. Not many exterior companies work with Vinly siding anymore and Cillessen does and beats the competition."
Robert Glenn
"Devon and Cillessen Construction are top notch. They honor their word and commitment to honest estimates and working with clients on insurance claims. They deserve a call if you have roofing or other exterior challenges or needs."
Holly Johnson
"Devon and Heath are incredibly competent, compassionate and capable to do more to serve their clients than anyone I have worked with."
Mark Brende
Start Your Home Addition Project
Get expert insight on expanding your home with a design and build approach that keeps everything aligned.
Share a few details about your space and goals. We’ll help you understand the best way to add square footage while keeping your home cohesive and functional.