G M D Construction INC

bottom line excellent work, good price, I highly recommend GMD Consttruction. quick response to getting a bid. Installation was done in 2 hours; excellent work; 50 yr caulk to seal the tube opening in the basement floor; electric hard wired into a circuit protected by a generator,; exterior power cutoff, fan and pipe to the roof line installed in a professional manner with secure standoffs for the pipe.

Could not have been any better. The office was responsive on initial contact, promptly scheduled, Came out and gave a detailed estimate and discussed their plan with real project photos. Very thoughtful on Options and strategy where to run the piping in a 29 year old house with not easy access for piping run. Detailed info on radon provided. They also replaced and sealed the sump pump which the two other estimates did not even consider. The crew communicated in advance on job start time. Mike and Clayton arrived right on time and were extremely professional and considerate, COVID-19 precautions with masks at all times, and they were done in about 3 hours; (much faster than others which said 1.5 days!) Cleaned up thoroughly vacuum etc. and went over system with me in detail. Their truck was well maintained, orderly with every tool and pipe connector possible. I got three estimates on this job. They GMD were not the cheapest of the three but the ~10 percent premium was worth it and included sump pump replacement and independent inspector testing follow up. Others bidders were cheaper and or did not account for follow up testing and/or did not give me confidence In their solution or capability to choose the best solution not the easiest one or cut a hole in my roof! I don’t write up many reviews but this was an experience worth sharing. Highly recommend. You won’t be disappointed.

Excellent company to do business with. Thoroughly explained the process and the solution. Accommodated our quick turn around request due to house sale. Did a beautiful job with minimal impact to both interior and exterior of house.

Great job. They explained the work to be done, provided a written quote, and completed the work as scheduled. Installers were on-time, efficient, and courteous. High quality work - no trash left behind, neat connections and caulking. Definitely recommend.

As part of a deck remodeling project, we wanted to relocate the radon system to vent through another side of our house. When Mike came over, he noticed that we had an existing but unused pipe that the builders installed for radon (but never connected to) which ran from the basement to the attic. He proposed that instead of venting through another side of the house, we could connect to that unused pipe and add a fan in the attic to vent through the attic and roof. The work was done professionally, and the crew left no mess inside. Their knowledge and experience left us with a better result than we originally envisioned. Will definitely use again in the future.

Mike and team were very knowledgeable and patiently answered all of my questions (and I always have a lot of them when dealing with contractors). They know their stuff and didn’t oversell or make false promises. I already had a mitigation system in place over my sump pit that came with the house, but it wasn’t adequate to service the multiple slabs that make up my foundation. Mike suggested a stepped approach to deal with the “hot spots” in the house and then re-assess whether additional action was necessary. They installed a clear lid over my sump and fixed the trap in my pit so that the existing fan was actually pulling suction on the foundation (and not the open drain from my exterior stairs). They also installed a second system that serviced two slabs and vented out through the back of the roof. Finally, they sealed up some cracks and holes around the foundations. Mike found a solution that was sensible from an aesthetics perspective as well as functional. The pipe runs through my entryway closet, and is as hidden and cleanly installed as I could have hoped for. We had a difference in opinion on how the finished roof flashing should have been done (more from an aesthetics perspective), but it’s on the back of the house behind the chimney so I wasn’t overly concerned about it. The system has reduced my levels to around 1pc/l down from a previous average of about 8 pc/l. So definitely within acceptable levels. I’m only a month in, so will continue to monitor over the next year to determine if any seasonal impacts require further action. I would definitely recommend them and plan to use them again if I need to (although I hope I don’t have to). If you are looking at this and don’t have your own continuous radon monitor, I recommend picking one up.

Excellent. GMD installed a system that was integrated into existing french drain, updated an existing sump pump, installed a duct fan, and sealed the entire system. They performed a smoke test to ensure air flow. Team took pains to leave behind a clean work area, were friendly, and willing to ask any and all questions. Radon following their test showed a significant drop in detected radon. Would highly recommend them to anyone requiring radon mitigation.

The vent stack that was attached on the side of my house broke loose during a recent wind storm. This was the first time that I had any issues with my 18-year old radon mitigation system that was installed by another contractor. I called GMD to reinstall the vent stack and check on the status of the operation of the system. Landon and his helper arrived early and wore rubberized-shoe protectors, which kept my house clean. In the end, the vent stack was replaced with a smaller-sized stack that was color coordinated with the gutters on my house, a "chimney cap" was installed to keep the critters out (they found a bird's nest in the original stack), and stronger brackets were used to install the stack. In addition, the decision was made to replace the fan since it was nearing its shelf life. My boyfriend and I would definitely use GMD's services again, as well as recommending them to friends and neighbors. Landon and his helper provided great customer service which is hard to come by these days, and it seemed like they finished the job in no time at all. They were very responsive to fixing the system even though they had not originally installed it, as well as answering all of our questions. We thought the cost for the work was very reasonable and even included an online coupon.

Excellent job, great customer service - they were in and out in no time. Landon Becker was friendly, efficient/quick (less than an hour) and explained everything to us, start-to-finish. They also put on house shoes to not track dirt. We had a passive radon mitigation system in our house and decided to make it active to lower the radon level since we spend a good bit of time in our basement. They installed a fan in the attic portion of the PVC pipe to draw air out from under the house. They also installed a fan monitor in the basement and sealed a couple areas including around the sump pump and another hole in our basement. A week later they had someone perform a radon test - Dean Wickline from Tidewater Home Inspection. We also have our own daily/long-term radon monitor (Corentium 223) which gave similar results to the test. Before the active system was installed we were getting an average of 2.25 pCi/L (picoCuries/Liter). Its now down to 0.5 pCi/L! Before our active radon system was installed, we were able to get our radon levels down by opening several windows in the basement and upstairs for an hour a day, but that’s a pain and it wasted a lot of energy during super hot or cold days. Another benefit of the active radon mitigation system is the fan should help remove moisture before it gets in the basement.

This work was performed in January 2017. GMD is a family business. I met Mike D. senior and his son performed the actual installation. They were prompt, clean, knowledgeable and reasonably priced. I found them to be ethical contractors who don't oversell or needlessly scare you to get business. They have been in this business for a longtime and know what they are talking about. I recommend that you look into the Radon levels in your indoor air and I recommend GMD Construction without hesitation.

Mike Dietz did an extraordinary job looking at my foundations. He actually discovered that a whole area of my house had an unexplained foundation -- something that neither my home inspector nor our termite inspector had noticed. When they did the actual system installation, they used Schedule 40 PVC pipe, just as the EPA recommends. The installation was clearly done with excellent workmanship and well thought through. The cost was $1800, but that was because we have multiple foundations, lots of cracks to seal -- and because they used the EPA-recommended top quality PVC. I highly recommend GMD.

Their work was top notch, very professional. I am very pleased with the quality of the system they installed.

Went great. The installation team was on time, explained what they were doing and left the basement area neat. They always discussed the other basement issue and told us what they thought the source of moisture was. This was important to us because the radon system was placed near the corner where the moisture was. I have been recommending this company to neighbors as often as I can.

The process from beginning to end was painless and very professional. The company owner came out to give us an estimate and he was very helpful in explaining the process and gave us a fair quote. On the day we scheduled for the work, the team arrived on time and finished quicker than we expected. The owner's son was one of the workers who showed up to do the install. They were very neat in the work they did. If we ever had to do this again, we would definitely hire GMD again.

The company was recommended to us by 3 different people. The company was very professional from the person answering the phone, the owner of the company who came to give an estimate and the gentlemen who came to do the work. They were not only punctual, they were actually a little early which was nice. Everything was explained thoroughly as to what they were doing and why, how the system worked and what to expect in the future for upkeep. The work was done quickly, they cleaned up after themselves extremely well and the company handled scheduling the follow-up testing. Very satisfied.

I had a radon reduction system in the house and it kind of looked like it was low pressure, so they came and inspected it, and the way that it was, there's actually a switch where it wasn't turned on, so whoever installed it in the house to begin with, before we moved in, had done it. So they kind of explained and showed us the system wasn't malfunctioned, just how to keep the switch on all the time. Then they gave us a test kit once it had been on for a few days, to make sure it was still reducing levels. So he sent that too. I followed the instruction and mailed that into the testing lab. That's all the services we used. There really wasn't a lot of work to do as far as the services I needed. The system was already installed. They came out pretty quickly. They gave a four- to six-hour window. They came within a six-hour window. It's not like we had a set time. I think their professionalism was fine. My wife was actually here when they came by. I set up the appointment, but I didn't hear anything negative, so that was good. I would use them again, but that's just because there's not that many places. There's really, at least what I was able to find on Angie's Lists and looking on Google, it was really the best option. I found places that could do inspections, but they couldn't do mitigation and then, I think it was mainly off of the Angie's List reviews, there were maybe three companies total that could do testing and mitigation within a reasonable distance to my area. They are kind of the only choice I was able to find.

They were excellent. Arrived ahead of time and got the work done most efficiently.

I contacted GMD, a very highly recommended Maryland radon remediation company. They were as good as the recommendations said they were. First someone came and talked about the issues and his proposed solution. I had educated myself before hand and his discussion meshed together with the scientific data and EPA guidelines perfectly. He and I agreed on the solution and scheduled installation about 2 weeks later. The crew that came to install the system were as knowledgeable as the first man and did a neat clean quiet job. We were pleased. And a follow up radon test conducted by another company showed the remediation system was very successful.

Work was performed well for a fair price. I would hire again!

The initial installation of the required hardware was fuctionally sufficient, however, workmanship was not entirely satisfactory. Upon request, the company corrected the problems. The system works fine and the workmanship problems were well resolved.

Excellent service coupled with professionalism, I could not asked for a better experience for this type of service. They were thorough and even after providing a estimate for the services, they re-evaluated the work needed and adjusted the final cost for a measureable savings for me. Customer service at it best.

He was professional, courteous and on time.

The work was done swiftly and with minimal impact to the house. Work to be done was explained during initial estimate. Cost was higher than another estimate, but fair considering materials used.

Very well. Mike, the president of the company, explained what needed to be done to correct our radon problem. The crew arrived on time, installed the system, explained how it all worked and left absolutely no mess behind. They arranged for a follow-up by a testing company to insure the system was working properly. Everyone involved was very knowledgeable and professional. We highly recommend this company.

Very pleased from start to finish. Mike came out to give me an estimate and explained the process. Work was scheduled, and Johnny and Tyler arrived exactly on time. The work involved installing piping into the basement slab, a crawlspace, and under a first story slab, a outside fan and pipe. They did a great job. They sent out an independent radon tester a few days later to confirm that the system was working. Highly recommend this company. By the way, I never knew there was radon in my area (Davidsonville) until I decided to purchase a Corentium Radon Detector after seeing an article about it in Family Handyman magazine. Bought it on Amazon... [*** Link removed ***] I was getting reading above 10 when it should be below 4. Radon is a dangerous gas that can cause lung cancer. I wish I knew sooner.