We loved working with K-One! Their communication was amazing, they plan well, problem solve quickly, and are a dream to work with for a big project like our new addition. I recommend them to everyone.

B. Chalkley

These guys were professional, and thorough. They were able to offer better breakdowns, details, etc. than several other contractors. Very competitively priced too. Had something come up on our end that will probably delay the process by six months, but hope to use K-One.

A.J. Nowaczyk

My wife and six children had a very pleasant experience working with K-One this past year to put an addition atop our garage to expand our home. The addition created a large bedroom for our two daughters as well as a home office/guest room. It also included a large closet where plumbing was roughed in for a potential future bathroom as well as some other modifications to create the addition and add new flooring to the whole upper level. K-One was very professional and highly responsive to every question or concern.

They provided us with a detailed estimate that was accurate and held throughout the project. If there were changes, change orders were signed and documented but those were for changes we initiated. When there were delays because of supply chain issues, K-One communicated that clearly. They knew that with a baby on the way this would be particularly important to us and were very mindful of that situation. They also took the time upfront to understand our goals for the project and to design and update a plan that would best fit our needs at the budget desired.

When work began, they stayed on task losing very little time and completing the core of the work in less than three months. K-One would provide daily updates along with more detailed status reports every couple of weeks. They responded to questions in a timely manner and were highly responsive. They also recognized the disruptions and took steps to minimize them, even going to all of our neighbors to advise them of the project and offering to address any concerns.

We have done other renovations before but nothing as extensive as this. We were very pleased with the work of the K-One team from the initial proposal and revisions through the final stages. They did great work, worked to minimize their impact on our home and were very kind. We enjoyed working with them and are very pleased with the end result.

Nick Manetto

K-One turned an unfinished section of our basement into a beautiful home office and cigar room. They showed up on time every morning and took care to do things right. The room was a bit awkward in terms of layout, but K-One wasn't dissuaded. They came up with some clever design ideas and executed their plan brilliantly. The work was meticulous and professionally done. Most important to us is that they are trustworthy and honest brokers.

I've recommended them to three other friends for upcoming projects. Keyvan and the team are now our contractors of choice, and we look forward to having them back to do our kitchen and bathrooms soon.

John Noonan

We popped up our house starting when COVID hit. K-One was great to work with. The best part was the design process. We consistently got excellent advice about what we should do while also listening to what we wanted which may not be typical for most customers.

Katie Klein Schultz

K-One does quality, reasonably priced work and stands behind their work. They replaced 2 roofs for me in 2017 and did a superb, highly skilled job. I recently had a problem with water leaking around the chimney. They responded promptly and professionally, and took extra measures to preclude further infiltration. I highly recommend K-One.

Dave Bunten

I have seen your projects...
100% Recommended...
Excellent work.

Eliezar Herrarte

Amazing crew. The quality of work is really high, very considerate to our requests and the fact that we were living in the house while the renovations were on the way. They cleaned up every evening. Excellent communication, always on time. Highly recommended. We actually hired K-One again for another job after they did the first set of renovations.

Ksenia Peguero

K-one is now my go to company. Trustworthy, honest, knowledgeable and detail oriented. Very responsive to all of my questions and their work was impeccable. They went above and beyond to ensure everything was finished well ahead of schedule. I have never had this level of customer service level of customer service from a company here in the DC Metro area.

If you are shopping for different contractors, make sure to give k-one a call. You won't be disappointed.

Lindsey S.

K-One is unlike any other contractor we've worked with. Ahead of the game, flexible, on time, and super responsive. If you're not sure if you should use them on your next project let us help: use them. As they say: you've tried the rest, now try the best! We are incredibly pleased will without a doubt use them on future projects. Thank you K-One!

Kendra Lee

We are very pleased with the work done by K-One Corp. In just 8 weeks, they completed a garage tear-down and built a new garage and a mudroom/laundry/pantry for us. Keyvan (owner), Jina (architect), Hassan (structural engineer), and all crew members were professional, friendly, and thorough. By the way, this is a family business with many years of experience.

The K-One carpenters are excellent! In addition, all subs that K-One uses (for concrete, plumbing, roofing, siding & flooring) do quality work. Keyvan was on-site almost every day, supervising the work, both for his crew and his subs.

Everyone was on-time, and sometimes early. The work was well-coordinated, so only a few days here and there were non-work days from start to finish. And most of those times were due to waiting for inspectors as phases were completed & we waited for approval from our county.

The many pluses of K-One Corporation include: 1) They stuck with their original proposed costs--although we (the owners) did request some added work, which adjusted the final cost. 2) The company is big on quality control. For instance, Keyvan inspected all cut wood before delivery to make sure it met his standards. 3) In the design process (before construction) we had several on-site mtgs with Keyvan and Jina to thoroughly/correctly plan final design and layout. 4) Keyvan and Jina were always available for questions, in-person, by phone, or by email. 5) Sarah, the business manager, who wears many hats, was also excellent assisting us throughout the prep and design/build process. 6) Keyvan is extremely dedicated to quality and customer satisfaction. And he is one of the nicest people you'll ever meet.

Marg Dee

Communication was great and the availability of Keyvan leading the crew was excellent. Any changes were explained in full with appropriate options, which made the working relationship very easy to manage.


We have been very satisfied so far with all the work K-One has done for us-- two projects (first small, second larger).

First project was converting an outdoor patio into a sunroom ( a sitting room with many plants). We interviewed three recommended prospective "builders", and was the first time we met K-One. The challenge on this project was engineering a proper roofline- both asthetically and providing maximum waterflow away from the house (a personal hot button for me). K-One created what we thought was the best concept. Another challenge was finding glass accordion doors we wanted. K-One did that too. Work was completed on time, within our budget tolerances, and no big surprises.

The second project was an entire house renovation. The challenges here were: ten years of deferred maintenance, the need to lower the concrete basement floor (to meet code for livable space), the need to re-engineer the stairway to the basement, and the need to waterproof the house. I interviewed three more prospective builders, then offered a shot to K-One. We liked their proposal and presentation the best, and selected them for this work too. We had no strict deadline because the property is intended as a rental and we wanted all work done as close to perfect as possible rather than finish by a "date certain". They were also very in providing design opinions whenever we asked. I have to say, in both case, we have been pleased so far with cost, quality, and outcomes. We particularly appreciated the timely communications (usually sent from Keyvan), updates, assessments, their handling of required permits, etc, even when we were overseas.

John Hastings

A great experience with this group. Communication couldn't have been better. Outcome of project exceeded expectations. Highly recommended.

Kathleen M Hastings

Great company to work with. I love my beautiful house they build for me.

Taslima Ahkter

Great people!

Natalie Malk

Very profetional

Santiago Rivera

So a beautiful manson

Uffoh Chibuike