G M D Construction INC

We had the mother of all radon challenges in our house. After settling on our home and receiving a small allowance from the sellers for the installation of a radon mitigation system, Mike and John informed us our radon problem was much more complicated than a simple installation of one system. Our house is a 1950s split slab foundation home and we really thought it was a lost cause and facing a very dire situation. However, after almost a year of chipping away at the problem, Mike and John came up with a multifaceted solution that now has our levels under the legal limit. They never gave up and exhausted all possible remedies before undertaking additional costs. We are so grateful to Mike and John that they didn't give up on us and agreed to take on this challenge. Our advice to other home owners? Stop your search now, you won't find anyone else that knows more about mitigating radon. And If you are looking around Baltimore county for a house - we suggest you have MIke and John in to inspect for radon issues/suggest mitigation remedies BEFORE you purchase especially if you are considering an older home. Don't let the seller choose who does the testing or mitigation! Thanks again Mike and John!

Mike and his workers were great. Good design, gear, and labor. Always on time and work done as explained... done in 3 hours. Had 3rd party test to verify results. Highly recommend.

Believe it or not, my 22 year old radon system and sump pump were still working but I realized I was on borrowed time. GMD immediately returned my call and came out the next day to give me a proposal. We decided to go with GMD because of its expertise and high ratings on Angie's List. We found out that the old radon system didn't meet code so GMD reconfigured the radon pipe by moving the fan to the exterior of my home, installed new pipes and greatly raised the height of the exterior pipe. Since the radon system and sump pump are co-located, we decided to have GMD replace the 22 year old sump pump as well. We are pleased with their workmanship.

G.M.D. Construction provided an amazing service! Mike Dietz was incredibly responsive to my urgent need for installation of a radon mitigation system. I had fired my prior contractor (Environ-Tech from MD's eastern shore - Do Not hire them!!!). G.M.D. was punctual and professional. They removed the partially installed system from Environ-Tech, and in one afternoon had completely installed a new system with 3 separate ports to a central exhaust fan. THANK YOU to Mike, John and Mike!!

Fantastic firm. Can't recommend these guys highly enough. Straight shooters that will tell you WHY they are doing what they propose. Those explanations can be extremely helpful if you are doing other work in/on the house like we were, as it caused us to re-think placement of the pipes and the timing of their work between other contractors. I also loved the use of an outside firm for auditing purposes. Very nice to have an independent home inspection report showing no radon in case we ever decide to sell the house.

GMD provided excellent service. Both Mike and his son explained the entire system prior to the job and after the work was finished. They were very professional and tidy. Would recommend them to others.

Highly satisfied with the work of G.M.D. Construction Inc (Radon Mitigation Services, Inc) . This family business (the Deitzs') were prompt and professional. They explained the methodology to rectify the problem and were very careful and courteous in their work in our house. We would highly recommend them.

Recently I learned that our radon levels were slightly elevated. I called several radon remediation companies. Several of them seemed good but Mike of GMD Construction seemed to be the most thorough. I appreciated the time he took to evaluate our home in advance of the remediation. Mike scheduled the estimate but called to ask to come earlier. He was on time for the re-scheduled estimate. His son does the actual install and he was also on time for this appt. Mike had a very thorough knowledge of what the work required. He noticed that we had two drains in the basement and identified gadgets that are put into the drain so that radon does not come up through the drains. No one else mentioned this during their estimate and was a selling point with me. The actual install went very smoothly and was quicker than expected. Mike's son went over all the details of the work and made sure I had no further questions. I am awaiting a call from the radon re-test company. Based on the install, I expect that the levels will be reduced to within the safe range. If not, I have been assured that they will come out to re-evaluate and re-install until the levels are attained. I was completely satisfied with the install and the timeliness of the install ( all within 8 days). If any further issues arise, I will update this review. Thank you Mike for making our remediation work so smooth!

I needed a radon fan replaced quickly in order to finalize the sale of my townhouse. Mike Deitz responded promptly to my phone call, made an appointment to come up within days, showed up on time, and replaced the fan as requested. He worked quickly and professionally, and patiently answered my questions about radon remission. I will not hesitate to call him for radon-related services at my new house, and highly recommend him to others.

They were awesome. I would highly recommend them to anyone. Mike the president came out and gave a thorough inspection and provided two estimates; one for internal and one for an external set up of a radon mitigation system. Mike knows what he is talking about as he has been doing it for over 20 years I believe. Was perfectly on time for the estimate and was there to answer any questions and provide background on the issue of radon. Then I called back and confirmed I wanted to go with him, he then promptly called me back and we scheduled a day in a week or so. On the day of the work, they came perfectly on time. I believe it was Mike's son and a helper. Extremely professional. Took his time to explain everything he was going to do and why they were going to do it. They then proceeded to do the work after which he fully walked me through what they had done and how the system would work and what I needed to know about the system going forward. I saw there was an Angie's list coupon for $25 off but had forgot about it at the estimate and before the work had began, plus they had did such a nice job that I was not going to bring it up BUT after he asked how I got their name, and I said Angie's list, he said well there is a coupon and then immediately gave me the 25 off! He didn't have to do that at all but he went ahead and gave me the 25 off the job cost. A real nice guy. I can only wish other contractors were as professional, courteous, honest, and do the level of high qualify work that GMD does. Folks should feel confident in using them to safeguard your house and family against the effects of radon. On last note is that they include independent re testing. The folks came in and did the testing but then I never heard. I called them back but they didn't respond so I called GMD who apologized looked into it and forwarded me to the results (eventually I also did get the results directly form the radon testing company as well). Again Mike and his company are simply first class and I wouldn't hesitate to use them again or highly recommend them. Great job GMD! Thanks for the great job!

This is one of the best contractors I have ever worked with-professional, respectful and accommodating! Truly cannot not say enough positive about Mike Sr. ,son Mike and John. Needed to remediate radon for a home that is going on sales market very soon. Mike was flexible -adjusting to fit my crazy work schedule. That was very much appreciated! Then on the day of our appointment, my vehicle needed work and I was running behind schedule. Again Mike Sr. worked with me. When Mike, Jr. and John arrived- they quickly surveyed the location of the installation, explained again what was going to be done, and started to work. They worked efficiently, work was neatly done and clean-up was excellent. I would highly recommend this company- for their fair pricing, professionalism and efficient work. Thank you for an excellent job.

Arrived on time. Got the job done. Enough said.

After analyzing the needed system to remediate a high radon level, they proposed a system from my basement to an exterior wall adjacent to my garage. After sealing the perimeter of the basement slab a vent was placed from the basement into the attic above the garage and through the roof of the garage. The pipes were placed aesthetically and avoided the typical ugly placement of pipes along the outside of the house. While the cost was a little higher than the outside placement of the ventilation system, my wife was very pleased with the more disguised approach. After the job was complete, an independent inspector placed a radon monitor in our basement for three days and confirmed the effectiveness of the remediation. I chose this provider as they guaranteed the result.

They quickly came out and had the new one installed in less than an hour

They are one of the few that are certified by EPA. We had tested our house before they did the work and the reading was higher than 15; safe level is 4.0. The Deitzes, father and son, do all the work. Johnny (the son) did the work on our house. He showed up exactly on time for our first meeting and I signed the contract at that time. The price was very reasonable and within what I expected. He showed up at 7:30 am two days later and completed the work by lunch. It seemed like a lot of effort working inside and outside the house but he was amazingly efficient. It was one of the all time best experiences I've had with any contractor and recommend him in the most positive terms. He reduced the radon level to 0.4! He also arranges for an independent testing company to re-test the house within the next week to make sure the system is operating as intended. That process also went smoothly and was done at his expense, not ours.

I think they did an extraordinarily good job. He was able to explain everything. He had a very low pressure presentation. He seemed to understand what he was talking about better than the other contractors that I had interviewed. Out of the five companies I spoke with he showed he had done the work for many years and that he knew so many important details. He seemed to have very good judgment about how to solve some of my tricky problems.

Pretty straight-forward. Johnny came and gave me an estimate for the work. He very patiently explained the process, what he would do at each step and why. When we scheduled the work to be done, they arrived early, got right to it and were done in no time. Very professional, reasonably priced and reliable.

GMD experience really shows. Their pricing was competitive and they showed on time and finished early, During the initial visit they worked with me to locate the outside pipe on the far end of the house so it would not interfere with a future deck addition. Friendly, reliable and honest. I highly recommend.

Everything went as scheduled and planned. No complaints.

Service was professional. Our problem--knocking noise caused by faulty fan-- was solved.

Excellent experience. They came in on time. Told me that it would take a couple of hours so I left and returned two hours later. They finished while I waited. The job was done professionally and the area was cleaned up. They explained what they did and how the system worked. They indicated that my basement was large so the system might not be reaching all corners of the area. I was told if there was a need for an additional system to be put on the other side of the house, it would be done at no additional charge. The basement was retested (fee for that was included in the GMD quote) and recorded a 2.3 level, well within the safe range. This was an excellent experience with a professional group.

The installation of the radon reduction system was excellent. However, mud was tracked in on carpeting and a humidifier drain was accidently disconnected resulting in a small flood.

We needed a radon evacuation system for our new home after the inspection turned up radon levels just above the EPA limits. GMD was very thorough and thoughtful in terms of the design of our system. They explained how the system worked, why they needed to do all that they would do, and were extremely knowledgable. They also really care about their work, and it shows in their workmanship. They put a lot of effort into minimizing the system's visibility from the outside of the house, which is much appreciated. Overall, we're very satisfied. We did not get competing bids to be able to say how their price compares to others, but they were dead on with what our realtor advised us such a system would cost. Regardless, the quality of the work was worth it!

First of all, we were pleased that they could accommodate our schedule for the FREE estimate. Mike came to our home in the evening. He not only gave us an estimate, but took the time to answer all our questions about the job at hand as well as a couple of other issues in the house. On the day of the service, Mike and Johnny arrived promptly and the work was done very quickly. We're happy with the new radon mitigation system Mike recommended. The "work site" looks great, clean and neat. As part of their service, they'll be sending someone, independent, to check our radon levels to make sure the system is working properly. We'd use their services again, and wholeheartedly recommend them to anyone who needs a radon mitigation system.

They did an excellent job. My radon level was about 4.8 in my basement, not terrible, but it needed to be done at some point. John came and gave me a quote the same day I called, since they were going to be in the area. My sump pump was not the proper type, since it was keeping the water level above the drain tiles, which kept my (unfinished) basement dampish. He recommended replacing it. He also examined the different options for where to run the exhaust pipe, and we ended up with the pipe and motor below a window (which is about five feet above the ground) on the side of the house , with the pipe turning and running along side of the downspout. I can now plant some tallish evergreens below the window to hide the pump part from view (of my neighbors). The hardest part was that they wanted to seal the crack between the concrete floor and the concrete walls, all around my basement. This required a bit of organizing, throwing out, and rearranging on my part, but it was well needed! They came promptly on the day scheduled, and installed the sump pump, the radon system, sealed all the cracks in the floor, cleaned up, and explained everything to me, in 2 1/2 hours. The re-test was done by an independent company a few days later, and the radon level is now 0.7. I am very satisfied with their work.