Custom Homes
A home built around your land, your family, and the way you really live.
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CornerstoneConstruction GroupRequest an estimateFamily owned. Proudly serving Delaware.
We bring honest work, hands-on experience, and personal attention to every home and business we build.
Serving Delaware and surrounding communities
Featured recognitionMarquis Who's WhoMillennium Magazine · 2022From our family to yours
Cornerstone Construction Group is a family-owned company built on hard work, straight answers, and pride in a job done right.
You deal with people who know your project and care about the outcome. We stay involved from the first conversation through the last detail.
What we build
A home built around your land, your family, and the way you really live.
Ask us about it →More room for the people and moments that matter, built to look like it was always there.
Ask us about it →Dependable construction and remodeling for local businesses, restaurants, and offices.
Ask us about it →We handle the hard structural work and stay with the job through the finishing touches.
Ask us about it →Built by Cornerstone
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Industry recognition
In 2022, Cornerstone owner John Knoeller was featured on the cover of Marquis Who's Who Millennium Magazine in recognition of his leadership, craftsmanship, and decades of hands-on construction experience.
Marquis Who's Who Millennium Magazine · 2022The Cornerstone difference
We know you are trusting us with your home, your business, and your investment. That is why we stay hands-on, communicate clearly, and never cut corners where it matters.
How we work
We sit down with you, hear what you want, and talk honestly about the job.
We work through the details together before construction begins.
We stay involved, keep you informed, and treat your property with respect.
We finish the job with the same care we would expect in our own home.
What our customers say
We purchased our new home at the end of October 2010. One of the first things we wanted to do was build a deck and porch off the back of the house. After reviewing several bids, we decided to use Cornerstone because the bid was professionally presented, covered all construction details, and included drawings, elevations, and site plans. John made himself available to meet with us and the Architectural Committee, was flexible, made good suggestions, incorporated our changes, and stayed in contact with us before settlement. He began work the following Monday. We also asked him to replace the downstairs carpeting with more than 1,800 square feet of hardwood flooring. John suggested laying it at a 45-degree angle, even though it created more work, and included moving furniture and removing baseboards as part of the job. The deck and screened porch was a major project involving a new roof. John's workmanship and work ethic were excellent. He arrived early, worked until late afternoon, kept a clean work area, and removed all trash and debris. He also handled additional carpentry, electrical, and plumbing work that came up. We would have no hesitation recommending John and Cornerstone Construction. His bids are competitive, his work is excellent, and he is reliable, personable, and trustworthy.
Uwe & Chris SchulzLewes, DEWritten letter of recommendationI just want to thank CornerStone Construction for doing an absolutely beautiful job. They completely gutted and transformed our house, worked with us on our budget, and were finished in our time frame. Thank you, John, for all of your help and the marvelous work you do!
Edward & Delores HarringtonDelawareJohn Knoeller is the most knowledgeable contractor we've ever met. We explained what we wanted; not only would he understand, he would immediately be able to discuss all the options and recommend the best solution. John was conscientious and tenacious in getting the job done and, more often than not, went the extra mile to satisfy us.
Chuck & KayNewark, DEToday Cornerstone Construction completed a total bathroom remodel. John was a Godsend. I believe he was heaven-sent! My husband and I interviewed several contractors before choosing John. I am very positive that we made the best choice. He knew exactly what I wanted to accomplish and, looking at the finished job, I couldn't be happier. John is very knowledgeable in many areas of construction. He is pleasant to speak with and listened to any concerns that I had about the project. He always gave his professional advice and opinions to assist me with all stages of the planning, design, and layout. I wouldn't hesitate to call him again for other projects. It is such a comfort to know that I have found someone whom I can trust and depend upon to do a quality job.
Mike & LisaDover, DEWe were looking for someone to replace our old wooden deck and rail. An initial bid we received seemed quite high, so when I happened across Cornerstone Construction's information, I decided to give John and Bridgette a call. John talked with me by phone to discuss options and then came to the house with samples. He provided us with options that we didn't know existed. Once we agreed to move forward, John's team started work right away. They even finished up in pouring rain because they had committed to completing the job in two days. Any questions or concerns were addressed swiftly and to our satisfaction. John and Bridgette are very personable, down-to-earth people. They make it their business to understand your concerns and then work with you to achieve the results you want within the budget you can afford. When referring a business, I only do so if I can see myself using the business again. In this case, I definitely plan to use Cornerstone Construction in the future!
A. GardnerWilmington, DEJohn and Bridget rescued us after three long years of attempting to begin the remodeling of our bathroom! It was a pleasure working with two people who were like family. It was so easy communicating with them. They did an excellent job, from John's construction to Bridget's color coordination. John graciously made adjustments requested with no hesitation. We were comfortable providing them with a key to our home during the construction, as we found them to be very trustworthy, which is important in today's society. We would not hesitate requesting them to do additional work in our home or recommending them to others. Everyone that sees our bathroom just loves it—it's the most beautiful room in our house!
N. HickmanHarbeson, DEI met John of CornerStone Construction through the Internet when I asked for local contractors in the Sussex County, Delaware area. John was the first contractor to contact me. We set up a time and date to meet at my mom's house, where the work was to be done. He was on time and very helpful and knowledgeable about the work I needed done. I had new interior doors and woodwork installed, carpet, hardwood floors, and tile installed, and a new staircase put in. All of the work was completed in the estimated time frame John gave me, and his estimate was very good and within our budget. I will call CornerStone Construction for future jobs and highly recommend them to others for any remodeling or home-improvement jobs.
Marty CarrollMillsboro, DEJohn, at Cornerstone Construction, is very knowledgeable in so many areas of construction and willing to share this knowledge with his customers. He is willing to work within your budget and tries to be fair. In renovating our 200-plus-year-old home, John allowed us to make considerable changes for a reasonable amount of money. He completed a number of jobs, large and small, for us—everything from installing a new energy-efficient boiler and tankless water heater to building new cabinets in our kitchen, sandblasting part of our home's exterior stone, and various plumbing and electrical work. When the job was completed, he was willing to come back to fix anything that needed it to ensure our satisfaction. John and Tim proved very trustworthy, and Bridget was especially pleasant to work with.
L. JalotWilmington, DELet's talk
Whether it is a new home, a major addition, or a business renovation, we would like to hear your ideas and learn how we can help.