G.M.D. Construction inc.

Located in Mount airy, Maryland

Address: 17530 Frederick Rd, Mt Airy, MD 21771, United States

Phone: +1 410-442-1960

Rating: 4.9

Services

Wheelchair-accessible car park
Wheelchair-accessible entrance

Photos

Latest Fire Recovery & Restoration Services

Comments

Review 1 (2024-12-30 - Rating: 5)
Great service and installation. Our Radon levels went from 5.1 to 0.4 in just a couple of days. GMD came up with a creative solution to install our system and showed confidence in their work that others did not. Would definitely recommend.

Review 2 (2025-01-01 - Rating: 5)
Professional and courteous installation crew. They arrived on schedule, were fast and quiet, and they installed an effective system. The cost for making my home a safer place to live was more than reasonable. The test conducted by an independent contractor prior to the mitigation showed radon concentration levels of 25 pCi/L. A test was conducted, at no additional cost to me, by an independent contractor after the mitigation system was installed. This final test showed a concentration level of 1.4 pCi/L. I highly recommend using GMD Construction for your mitigation needs.

Review 3 (2024-10-10 - Rating: 5)
GMD was great to work with. They were efficient and professional. The radon level in our basement dropped below detectable levels after the system them installed. Highly recommend.

Review 4 (2024-12-07 - Rating: 5)
GMD solved my houses radon problem, one that I thought was unsolvable, because another company had failed to solve it. They were quick, clean, efficient, thorough and friendly. I dont know what else a homeowner could want.

Review 5 (2024-10-15 - Rating: 5)
Professional installation that included a 3rd party inspection afterwards to measure radon levels (reduced 44 times down to very low 0.9 pCi/L as a result). The team was punctual, left the work site clean, took the time to inform me on the system and what I should pay attention to over time. I recommend GMD for a complete solution to radon mitigation.

Review 6 (2024-11-13 - Rating: 5)
They did a great job installing a radon mitigation system. It was quick, clean, and at a reasonable price. Radon level went down to 1.8. Thank you!

Review 7 (2024-05-30 - Rating: 5)
We purchased a new home and waived inspection (ugh, I know). We performed a comprehensive inspection and discovered radon levels well above recommended levels. We haven’t even moved into our home yet and this company evaluated our home, presented options, and got the job done for a great price prior to us moving in. Reports from a 3rd party resulted in undetectable levels just days after install. So relieved to have this addressed in such a prompt fashion. Couldn’t be happier with the work done. Highly recommend GMD with no reservations.

Review 8 (2024-06-26 - Rating: 5)
We had a great experience with G.M.D Construction. Mike came to the house and did a thorough search of our finished basement to find the best place to install the system. The other companies we called for an estimate said they would install the system right in our sump pump and only gave quotes without coming to our home for inspection. Using the sump pump to mitigate radon is NOT code in Maryland and we are so thankful Mike knew the code and how best, to do the install. John and Tyler came to the house as promised. They were professional and worked together to give us an excellent functional and esthetic finished radon system and new sump pump. Our sump pump had quit working so it was convenient to have it replaced at the same time as the new radon system installation. They cleaned up after the job was completed. What excellent contractors! Id say they are the most knowledgeable and best performing Howard County Radon mitigation company.

Review 9 (2024-10-01 - Rating: 5)
We had G.M.D. install a Radon Mitigation system in our house which covered the basement slab as well as the slab under our family room. This install lowered our pCi/L from (8) to an average radon level of (.2) . We are very pleased with the excellent and very neat work they did resulting in a great outcome.

Review 10 (2019-03-05 - Rating: 5)
Did a web search and found these guys. I contacted two companies for a bid and Hear back fast from Radon Mitigation Services.The entire experience was just about perfect. I have no complaints. It was a little more than I wanted to spend initially. However the owner did a good job explaining the benefits to do the job right.Because I have a finished basement and several kids who sleep down there, it was worth spending a little more than their competition to do the job properly the first time. The other estimate I got was over email without wanting to come out.The job was done on the day that was scheduled. The crew arrived on time and were very professional. The installation was also well done. I reviewed the install when I got home from work. The caulking, piping, fan, everything ...no corners cut.I have not had this type of professional service in Frederick by other service contractors in the years I’ve lived here. I’d highly recommend.

Review 11 (2024-09-24 - Rating: 5)
Job completed on schedule at the quoted price. Workmanship is excellent. Follow up radon test demonstrated the effectiveness of the mitigation installation. I would recommend this company.

Review 12 (2020-06-18 - Rating: 5)
We decided to choose RadonWorx (GMD Construction) to handle our radon mitigation. They were not the least expensive but after Mike Deitz left my home, he showed me that his experience was the difference between his company and any of the others. He gave me great tips and information on what to do to further mitigate the radon even before his team came to the house. When they did arrive, both workers were very professional. They were not only installing the Radon mitigation system but also replacing our sump pump (which hadnt been working for a long time) as well as cleaning out the pit and unclogging the connecting pipes. Tyler and Clayton both were very professional and worked diligently to complete the job. Tyler answered any and all questions I had about the installation and he was very knowledgeable. It took about 3.5 hours but when they were finished, we were very impressed with the work, the cleanup and the overall competency of all involved. We have our retest next week to see that the radon levels are at 4 or below and I expect that to be the case. I would highly recommend RadonWorx for radon mitigiation as well as sump pump repair.

Review 13 (2024-07-13 - Rating: 5)
Outstanding Radon Mitigation Service from G.M.D ConstructionIf youre in need of top-tier radon mitigation, look no further than G.M.D Construction. Their expertise transformed our 1970s ranch house, which already had an active radon system, into a safe haven. While not the cheapest option, their meticulous approach and comprehensive solution were well worth the investment.From the outset, G.M.D Construction impressed us with their thoroughness. Unlike previous radon “contractors”, they didnt just patch up the existing system or offer some half-baked solution that may or may not work; they diagnosed and corrected the underlying issues. Our 100% finished basement posed a challenge due to recently installed partial interior French drain, to fix our flooding basement from seepage, which we suspected exacerbated the radon problem. G.M.D Construction tackled this with a unique strategy tailored to our homes needs.Despite their busy schedule, which necessitated several weeks wait for installation, their results were immediate and impressive. Previously, our radon levels fluctuated between 7-14, but now consistently measure under 1.0. On some days, readings even dip as low as 0.5, peaking briefly to 1.4 during an intense rainstorm and weather —an exceptional improvement.G.M.D Constructions dedication to excellence shines through in every aspect of their work. Their professionalism, expertise, and unmatched service make them stand out in the industry. If youre serious about radon mitigation and demand nothing short of the best, G.M.D Construction comes highly recommended without reservation.

Review 14 (2024-09-12 - Rating: 5)
Technician was knowledgeable. Took time to explain everything . We needed a new sim pump and radon mitigation system all done seamlessly. Would highly recommend

Review 15 (2024-04-15 - Rating: 5)
Working with GMD to install radon mitigation has been great. John and Tyler did an excellent job with the installation. They worked with us to place the system exactly where we need it to finish the basement in the future. Work was fast and very clean, and we’d definitely recommend them.

Review 16 (2024-10-05 - Rating: 5)
These guys were great. I can’t thank them enough. I made a dumb mistake and didn’t check the switch outside. They came all the way out to see why our system wasn’t working, flipped the switch, and didn’t even charge me! I’m sure they can’t always do that - but this customer very much appreciated it! Thank you.

Review 17 (2023-10-29 - Rating: 5)
I was very impressed with the level of experience and knowledge of the inspector and installers. They took time to explain where radon comes from, the possible health impacts and the remediation options. They then developed a solution for my house that minimized the intrusion into the interior and made it as cosmetically concealing as possible inside and out.I received three bids for radon remediation and while GMD was the most expensive, I felt most comfortable with their expertise and solution.The installation went as planned with two installers. They were very professional, took pride in their work, cleaned everything up and answered any questions I had.The follow-up radon test by Hill Environmental Solutions validated that the radon levels had been significantly reduced.I highly recommend GMD for your radon remediation needs.

Review 18 (2020-05-19 - Rating: 5)
If I could give them 6-stars, I would! Super professional. Real engineering and super high quality construction work. I have 110% confidence in the system they installed. Showed up on time and finished the job same day as they promised. No corners cut anywhere. I will make sure all my neighbors know how happy I am with G.M.D. Construction. Crawlspace looks so good!

Review 19 (2020-08-28 - Rating: 5)
Excellent. Patrick and Clayton know what they’re doing. They installed a two-port radon mitigation system. They took the time to do extra repairs for no extra charge. They felt it would add to the safety of my home for my kids. I definitely recommend them.

Review 20 (2024-02-02 - Rating: 5)
Cant recommend them enough. Ridiculously thorough during our radon inspection. Probably spent two hours here because our basement is so large with an addition. Day of service they were right on time and done in less than four hours. The final product (pipes, sealant, fan installation, etc.) looked unbelievably professional and our readings have dropped below 1 across the entire house. Im recommending them to everyone we know in the area.

Review 21 (2024-03-29 - Rating: 5)
GMB Construction did an awesome job - took my house from a 9 Ci/L all the way down to outside levels (0.4pCi/L). The team also went above and beyond by replacing my sump pump lid assembly and sealing various cracks in the cement. Highly recommend!

Review 22 (2024-04-26 - Rating: 5)
I’m happy to share that the G.M.D. team did an excellent job of installing our radon mitigation system, and for an extremely reasonable price! They also went ‘above and beyond’ in all aspects of their workmanship, and they thoroughly explained all the components of this system to us. Our radon levels are now consistently below 1.0 pCi/L. I had interviewed or spoken to several companies before selecting G.M.D. to do this work for us. Once I met with Mr. Deitz (from G.M.D.) the decision on which company to choose was an easy one. He went through our entire home conducting a thorough and careful inspection before making his recommendations. His many years of experience and fund of knowledge about radon mitigation are quite impressive! I don’t often take the time to post reviews but in this case I truly felt I should ‘spread the word’.

Review 23 (2024-03-04 - Rating: 5)
Edit. We use Airthings sensors to monitor our home air quality and our radon levels have been almost always below 1 since they installed our system. Our home is safe now.I’m not surprised these guys got so many 5 star reviews. We talked to them twice, 6 months apart and monitored our home’s radon levels in that time. The room just over the location where the sewer line goes out to the septic is where we found the greatest concentrations of radon hitting a high of 40 during our monitoring. We mitigated by keeping all the windows and a sliding door open. Daily rates were usually above 5 or 6. Then they came in and installed the system 3 months ago. Our home has been under 1 ever since in every room. We use air things to monitor radon as well as humidity and carbon dioxide. Great service, expert knowledge and reasonably priced. We’re happy and we sleep well with the peace of mind

Review 24 (2023-08-18 - Rating: 5)
I rarely write reviews but we were so happy with the work they did that I felt I should share. We initially measured 14.7 on our Radon levels(EPA max is 4.0) and now after the work they performed our Radon is now less than .4! These guys are friendly, knowledgeable and do very clean work. I would highly recommend them to anyone needing radon remediation.

Review 25 (2020-09-15 - Rating: 5)
Radon mitigation project - Got 3 estimates. GMD was not the least expensive but their estimate included independent post-mitigation test by home inspector and replacing and sealing sump pump. In the end they were the best choice by far.Compared to others They really thought through and came up with the best options for minimizing piping runs and placement of floor and roof access. Estimator arrived early and was clear and wrote the estimate on the spot showing me color real photos showing what installation would look like from their past work. Shared info on radon and impacts etc.Office staff quick to respond and set up aappointments. Installation crew Mike and Clayton were fast, neat and very professional. COVID-19 sensitive. Job took only 3 hrs and turned out even better than I expected given our layout.From the tools on their tidy and clean truck to their thought process and painstaking measuring, Obviously they have done a lot of these systems and everyone benefits from that experience and confidence in their work. The system is virtually invisible and every gap is sealed and the roof pipe access work looks snug and was well sealed and caulked (I watched!)Usually I am writing reviews here for bad or so-so service but this one was such a good experience I had to share. Thanks Wendy,Mike, Clayton and Gary for great service. Wish every contractor could be as conscientious.

Review 26 (2019-10-09 - Rating: 5)
This company was great to work with, they came out right away to give us an estimate on a radon system and within a month we had the system installed. We already knew our radon levels were high in the home but needed someone to come and mitigate. They were able to install the system within a few hours, even with the added work I requested of them, hiding the pipe behind a wall. The office staff were also very professional and pleasant to deal with when setting this job up. As far as house projects go working with GMD was great and I am glad we called them for our radon mitigation services.

Review 27 (2023-12-29 - Rating: 5)
Honest and quick. They could have charged me for a service call, but instead kindly pointed out my stupidity over email. The levels hadnt actually moved, I hit the tube a little while taking out Xmas decorations 🤦‍♀️🤦‍♀️

Review 28 (2023-10-27 - Rating: 5)
After a Radon test showing 4.9, which is above the recommended EPA guidelines, we chose G.M.D. Construction to put a fan in our 8 year old home to mitigate the Radon. G.M.D. is a family owned company with 40 years of construction experience and many years of Radon mitigation experience. John Dietz, the company founder’s son, installed our fan and was on time, thoroughly explained what we needed and what he was doing and completed the work with speed and expertise. G.M.D’s price included a professional retest of our radon level by Hill Environmental Solutions, a very professional radon testing company within days of the installation. Our Radon score went from 4.9 to .9. We are very satisfied and relieved by addressing our Radon problem.

Review 29 (2023-10-27 - Rating: 5)
G.M.D Construction is a great company! We took a home radon test a couple of months ago, and the result was 2.9 pCi/L. So, we called G.M.D, and the technician came out to our house, and worked for hours in the basement and attic installing what was required. A few days later an independent company came out and conducted their own radon test. Later in the week we received the results, and the level is now at .7 pci/L. Four times less! We thank you G.M.D Construction! We highly recommend this company!

Review 30 (2020-07-21 - Rating: 5)
Excellent experience with G.M.D. Construction on the installation of a radon mitigation system. Communication was very good from my first call to line up an estimate to lining up a time for installation (3 months later). Tyler and his partner (sorry forgot his name) were very professional. They did an initial walk through of my situation and explained what could be done. Before the end of the day I had a full description of the work and an estimate to include all company certification paperwork. Tyler suggested that I wait until my new siding was installed before they would install any new system. No strong arm sales tactics. Once my new siding was complete I called their office and they scheduled an appointment to install for the very next day. All installation was professional and they went over the entire system with me. I would highly recommend you look at G.M.D for your radon mitigation needs.

Review 31 (2020-10-15 - Rating: 5)
We had an incredible experience with GMD installing our radon system. Out of 3 companies, they were more expensive but we went with them because of their knowledge, professionalism, and customer service. They gave us many options on how and where we could install the system so that it wouldnt be an eye sore. When they came out for the estimate, the owner himself arrived and took his time to go over every aspect of the system and installation. The crew that came out were so pleasant and did such a clean job on the installation. They took their time and ensured that their radon system could work with our waterproofing system. We love working with small family companies because of the positive experience we always have and this was another small family company that we were extremely pleased with! They were worth every penny extra!

Review 32 (2023-10-04 - Rating: 5)
GMD was a lifesaver. We had another company attempt to handle our radon issue and failed. GMD came to our house to assess what we needed. Actually spent more time testing and understanding what we needed done than the competitor spent unsuccessfully attempting to resolve our radon issue. GMD know what they are doing and care about helping you.GMD proposed how to resolve the radon issue and successfully resolved our radon issue.If you are looking for radon resolution, I highly recommend GMD. They were excellent- 5 stars plus!!!!

Review 33 (2020-11-16 - Rating: 5)
GMD did an outstanding job of installing our radon mitigation system. They took the readings from over 4 to .4 and provided a guarantee for the system. They were quick, efficient, professional, spot on with their estimate, friendly, and most importantly took great care of our home while doing the intensive installation. Outstanding job!!! Highly recommend!!!

Review 34 (2021-02-28 - Rating: 5)
GMD construction did an excellent job installing our radon mitigation system. They showed extreme professionalism with their quick response time and attention to detail. Most of all, I appreciated them taking time to explain the ins and outs of their decision making and how their system worked. I would definitely recommend GMD to anyone looking into getting a radon mitigation system installed.

Review 35 (2020-07-04 - Rating: 5)
Mike and his installation team (Tyler and Clayton) are so great. They showed on agreed upon time and were so punctual & professional. They cleaned the area so well when they left the only way you could tell there were the great work they left behind. Very reasonable price and quick response for quote and installation. It is wonderful to work with. Highly recommend!

Review 36 (2024-01-17 - Rating: 5)
I dont normally leave reviews, good or bad, but Tylers work at our home was outstanding. Great communication, thorough, friendly, fast, efficient. Quite pleased with the work.

Review 37 (2024-05-07 - Rating: 5)
This company is a class act. They KNOW what they are doing and do it well. High quality work and customer service that I haven’t seen in a long time. Very impressive. So glad we went with them.

Review 38 (2024-11-15 - Rating: 5)
Timely, neat and great customer service. So easy to work with. Highly recommend!

Review 39 (2020-08-21 - Rating: 5)
I used GMD Construction to replace an old radon system. They are very thorough and meticulous and take pride in their work. Ive been impressed with their professionalism from my first phone call through a job well done. The quality of the work is excellent.

Review 40 (2020-12-29 - Rating: 5)
Very professional and knowledgeable team. It was great that the CEO himself made the initial consultation in person at my place when other companies wanted just to quote via phone interview. The work was done quickly and with no disruption. My Radon system is working well and keeping levels low since installation.

Review 41 (2017-11-21 - Rating: 5)
Professional Professional Professional!!!! These guys know what their talking about and their work was TOP Notch A Class!!!! Very Clean Neat Job and very respectful of my home.I did have 2 other estimates which Im not going to lie were Cheaper BUT in my case 2 separate units were going to have to be installed due to the fact I had 2 separate concrete slabs, Plus the one system needed some serious routing to get it right and I had one company giving estimates over the phone and another the guy didnt even go into my crawl space to inspect the foundation...BUT when Mike the President of the company and one of the first People to get involved with radon came out and inspected my property I was Convinced that this was the man for the job.He explained every aspect of the job in full detail, he inspected every corner of my home, crawlspace, foundation etc and guided my knowledge of radon to fully understand the risk and what I was dealing with.His son John whose the Vice president and another worker did a Great Job, Installed 2 units and it was like they were never here. Highly recommended Family Business!!!!

Review 42 (2021-11-08 - Rating: 5)
Worked with them for Radon mitigation. Very professional, no nonsense (but certainly with a sense of humor and respect), and reasonably priced. Mike came out for a quick estimate and carefully worked out exactly how to install a fan in a fairly congested area. He also had great advice on how to properly test for radon in our water when it comes to that (unfortunately, they arent able to provide that service, or Id happily hire them for it).John did the work in one [chilly] morning, walked us through exactly how the system needed to be maintained (which is mostly keep an ear out for problems with bearings and watch the pressure gauge), and kept the work clean and neat. Weve gone from an insane max of 27+ pCi/L to a max of 1.0 (measured through a personal digital meter).We could not be happier with the work done.

Review 43 (2020-04-08 - Rating: 5)
GMD did my radon mitigation. They were prompt to schedule an appointment, showed up exactly in tome, did fantastic work, showed me everything I needed to know. Great company that my family has used at two of our homes. Recommend them highly.

Review 44 (2024-12-02 - Rating: 5)
After learning that the radon level was high in our home, we contacted three companies to get quotes for a remediation system. G.M.D. Construction was the only company that actually came to the house to review and provide an estimate. Other companies provided estimates w/o seeing the house. GMD Construction spent a lot of time evaluating our house, answering numerous questions and designing a system to fit our needs. They arrived on time for installation and did a very professional job. The radon level in the house was tested by an independent company post system installation and it was 0.3pCi/L. This level was consistent with a continuous radon level monitor we procured. I would highly recommend G.M.D. Construction.

Review 45 (2016-01-08 - Rating: 5)
Home Inspection was done by Accuspex by Mike Kimble. He was very professional and the also did theCRM radon test. The test failed with a reading of 8. Based on his experience working with mitigation companies he recommended GMD Construction Services owned and operated by Mike Deitz. Being the skeptical and cheap person I am, I also call two other companies for estimates. One gave me the detail over the phone, the other came out the following day. GMD was scheduled to come out the next day for their estimate. All estimates were within $ 50.00 of each other. But the level of professionalism and attention to detail displayed by Mike Deitz was superior as well as his presentation of his estimate and documents. We scheduled the installation for 3 days after the estimate and I was given a time and told he would have his 2 techs out and should be done in about 90 minutes. On the morning of install I called and confirmed the time. I had to go out and run some errands. About 45 mins prior to the appointment time I got a call from the lead installer telling me they had finished early and were already on site. He asked if would be ok if they started early and after he told me his name, I realized he was the son of the owner. I told him I would be there in 20 mins and also where the spare house key was located. I arrived and was greeted not by 2 techs, but 3. It seems one had a light schedule and came to help out. The had the job done in just over an hour and the way they handled their business was top notch. They took care to locate the system where it would be inconspicuous and aesthetically pleasing. They were extremely professional, courteous and cleaned up after themselves. The thoroughly explained the system and completed the paperwork.The nice thing is that their price included cost of the follow up test with the original home inspector instead of leaving behind the self test kits I would have to mail. They scheduled the inspector and he completed his test several days after the installation. By taking the time to seal all floor cracks, and visible gaps , and installing the system, the end result of the new radon test reading was

Review 46 (2020-05-23 - Rating: 5)
GMD Construction put in a radon mitigation system May 2020. They did an excellent job. The estimate was affordable and the installation crew showed up on time and finished in two hours. The estimate crew answered all my questions honestly and professionally. I highly recommend GMD.

Review 47 (2020-12-24 - Rating: 5)
Radon mitigation. 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.

Review 48 (2020-05-24 - Rating: 5)
The GMD guys were AWESOME! They came out a year ago and provided an estimate for a Radon mitigation system. We were unable to install it at that time (family obligations), but contacted them a year afterwards. They honored the quote, down to the penny. They walked me through their COVID-19 protocol over the phone so we knew what to expect when they arrived. They answered ALL of my questions and concerns with patience, experience, and knowledge, which I greatly appreciate (these are challenging times and everyone is stressed and super-cautious). They were prompt, professional, knowledgeable, honest, and efficient. Since they installed the system during the COVID-19 pandemic they were very cautious to minimize contact, maintaining the six foot separation at all possible times. They entered with face masks, booties on their shoes, and head to toe clothing (long sleeves/pants). A few days later they performed the independent Radon testing and our in-house levels had dropped more than 75% of what it was prior to installing the system. I HIGHLY recommend their services!! Thanks Guys!!!! :o)

Review 49 (2020-07-22 - Rating: 5)
I cant say enough good things about this company. They came and replaced a radon system in my home that was too loud and ran up the front of my house! I had other companies tell me what I wanted couldnt be done. G.M.D. met the challenge drilling through two cinder block walls to install a new system that is super quiet and efficient! They were on time, polite, cleaned up everybit of debris. I am a happy lady!

Review 50 (2024-09-28 - Rating: 5)
I was very pleased and impressed by the work performed by GMD Construction at my home. John and his co-worker arrived exactly on time, patiently explained the radon mitigation system and new sump pump to be installed and performed the work in a very professional and expert manner. Both were very courteous and had time for my questions and concerns. They also performed some other work they thought necessary that was outside the scope of the contract, at no additional cost. The clean up after completion of the job was excellent; in-fact, they left the basement and garage neater than before they arrived. I highly recommend GMD Construction for their services.

Review 51 (2020-06-04 - Rating: 5)
Just had new radon system put in today. Very happy with this family owned company. No nonsense, very polite, on time and put shoe coverings on when they came into the house which is a nice touch! Very happy with the job they did and the time they took to explain everything! I would not hesitate to use this company again!!

Review 52 (2020-04-11 - Rating: 5)
Tyler and Patrick did a great job installing our radon mitigation system. Very professional and respectful of our home. Would recommend to anyone needing similar work done.

Review 53 (2024-09-26 - Rating: 5)
The experience, time, attention, design, and effectiveness sold me on this company. Ive referred them to clients and used them myself. Whats even better is that their prices are phenomenal. I highly recommend GMD Construction Inc for Radon Mitigation Services!

Review 54 (2020-03-16 - Rating: 5)
I have been using this company for over 25 years and have always thought extremely highly of them. This week, they exceeded all expectations by meeting me within 12 hours at one of my listings. They came up with a extremely thoughtful design and plan to remove the radon from the basement. They dont always look for the quick fix. They look for the best overall solution for the house. An amazing, local, family business that I would heartily recommend to anyone! Georgie Berkinshaw, #1 Coldwell Banker Agent, AA County 2020.

Review 55 (2017-04-10 - Rating: 5)
Very good experience with this company.From estimate to scheduling to the installation of our new radon system, we wxperienced knowledgeable staff as well as prompt and courteous service. I would highly recommend this company to anyone looking to have radon testing done in their home.

Review 56 (2024-08-01 - Rating: 5)
We have a complicated house that had been massively remodeled - presenting a lot of challenges. It passed inspection when we bought it, but subsequent (long-term) testing revealed levels around 6 - well above EPA standards. GMD was exceptionally thoughtful in their mitigation approach, seeking to maximize success while minimizing costs. We could not be more pleased with the results (which, throughout the house, are around 1.5 or lower). Thank you, thank you, thank you.

Review 57 (2021-06-09 - Rating: 5)
Great experience. They resolved our radon issue and were very no-nonsense and responsible. They also guarantee their work that they will get radon levels below 4 (for my house they got us from 15 to .8).

Review 58 (2024-07-26 - Rating: 5)
We had our new home tested and the radon levels were extremely high. G.M.D. Construction came out and installed a fan and cleaned out the sump pump among other much needed services. Follow up testing showed drastic changes for the better. Thank you so much for a job well done!

Review 59 (2020-10-13 - Rating: 5)
Radon Fan install. Very Professional. Showed up on time and completed work promptly. Discovered my sump pump was no longer working and replaced that at the same time. Very satisfied with results. Wore COVID mask the whole time. Would definitely use again

Review 60 (2024-07-30 - Rating: 5)
First rate service. Made the whole process extremely understandable, install was a breeze and extremely professional, no mess and the system works perfectly. Highly recommended for radon mitigation.

Review 61 (2020-01-02 - Rating: 5)
Very impressed with the efficiency, knowledge and teamwork demonstrated by Tyler, Patrick, and John. Felt comfortable at first meeting. I feel foolish that I waited so long to call the right company. I want everybody to get their radon tested and breathe healthy

Review 62 (2020-05-08 - Rating: 5)
Technicians were extremely professional. They explained in advance every step of the project and asked if I had questions. After completion they reviewed everything done and explained how system would operate and what to expect in the case of a power outage.

Review 63 (2019-03-28 - Rating: 5)
Great experience - did a great job on a complicated install, then came back on a service call a few years later when the system stopped working. Effective troubleshooting, repair, and honored the warranty - the only charge was a $150 service fee

Review 64 (2023-09-19 - Rating: 5)
We very much appreciated the punctuality, professionalism and care for details we received. I can highly recommend the company to anybody needing radon remediation and related work.

Review 65 (2023-05-12 - Rating: 5)
John was fantastic! Punctual and extremely knowledgeable. Educated us about the work he was going to do and why each step mattered. Could not recommend more highly.

Review 66 (2020-10-09 - Rating: 5)
Mike and Tyler, and the office staff, were awesome. They were very professional and knowledgeable. Work was clean and exactly what I needed. I will definitely recommend this business to friends and family who need the same service.

Review 67 (2024-08-22 - Rating: 5)
It was a good experience. Very professional, timely service and knowledgeable technician

Review 68 (2020-04-11 - Rating: 5)
Tyler and Patrick were outstanding. They installed a radon mitigation system very quickly and effectively, were very knowledgeable and politely and thoroughly answered all questions.

Review 69 (2024-02-08 - Rating: 5)
Great company! Wendy is awesome, she goes above and beyond for customers. I would highly recommend this company!

Review 70 (2020-07-13 - Rating: 5)
John and Pat did a great job with my Radon system. They were thorough, honest, neat and friendly. I highly recommend GMD!

Review 71 (2020-07-20 - Rating: 5)
Had GMD come out to house this morning to install home radon mitigation system. I appreciate that they hire an independent company to test system! Shows integrity

Review 72 (2024-08-19 - Rating: 5)
Great work! Very fast, neat and clean!

Review 73 (2017-09-25 - Rating: 5)
Fantastic experience from beginning to end. Family owned and operated. Reasonable price and very professional. I would highly recommend them if you need to mitigate radon gas in your home.

Review 74 (2020-06-12 - Rating: 5)
The work was done promptly and professionally. They took the time to explain the cause of the radon and the mitigation process. Highly recommend!

Review 75 (2018-01-23 - Rating: 5)
What a great company! They were quick, they couldnt be nicer, and they did a beautiful job! Radon went from 20 to 1 within the week!

Review 76 (2020-08-13 - Rating: 5)
On-time (even early!) and incredibly honest, informative, and professional. Gave information on possible paths forward. No pushy sales pitch - just honest service.

Review 77 (2024-03-19 - Rating: 5)
G.M.D is a small family owned business. They did an excellent job installing an active radon system in our house. Part of their job included an independent radon test after the installation to verify the system was working. I highly recommend them.

Review 78 (2020-07-23 - Rating: 5)
You dont have to look any further than Radonworx to get the best in radon mitigation. John & Tyler excellent service.

Review 79 (2024-04-28 - Rating: 5)
They are very professional and didn’t oversell what they can do at all. I cannot stress how impressed and happy I am with the mitigation system GMD installed after discussing different options.

Review 80 (2023-12-04 - Rating: 5)
Highly recommend! When we found our existing radon abatement system wasn’t working, and the company that installed it wasn’t around, we were panicked. John from GMD came in, calmly assessed the situation, gave us a tutorial on radon abatement methods and came up with a plan to expand our system. Installation went smoothly and testing shows our radon levels are now well within acceptable limits. This company is incredibly responsive and professional.

Review 81 (2023-09-15 - Rating: 5)
Excellent professional radon remediation installation. Highly recommend this service.

Review 82 (2024-03-15 - Rating: 5)
Did an amazing job for a reasonable price. 10/10 would recommend.

Review 83 (2017-12-29 - Rating: 5)
Wendy and the staff are very knowledge about radon and educating consumers about radon and it’s effects on your health! 5+ Stars!!

Review 84 (2022-08-17 - Rating: 5)
Tyler, John, Wendy, and Brittany,I wanted to thank you for such an amazing experience. Oftentimes people are loath to have people in their homes and face uncertainty of how it may go. From the first interactions with Wendy via email and phone, to the last interaction with Brittany on the test results, it was all amazing. I cant praise Tyler enough for his ability to listen to me at the first meeting and take my concerns seriously and design a system that does the job and meets my concerns. Tyler and John did a stellar job with the installation, perfect attention to detail and hard working They kept the job clean and they treated my puppies with love, ensuring they didnt flee the home during the work. Truly impressed from end to end. In the end the radon levels tested at great levels, but more vital is that we havent heard the fan, or the sump or the check valves. Perfection.I highly recommend for your Radon needs. The team is a great team for sure. My only regret is that they work on such a narrow problem set; Id love to have them do all the projects in my house.

Review 85 (2023-09-28 - Rating: 5)
The people who came and replaced a non-working system that was just vented to the outside through the wall about two feet about the ground next to the house.B.M.D. Construction inc. were very professional and polite and the system they installed consisted of an external fan and electric switch. The pipe was extended from that point to above the roof level so that the radon is not able to enter the house as the previous system had. This new system has already reduced the level of radon in the basement to average reading of between 0.9pCi/L to .43pCi/L after a period of two weeks constant monitoring.I also purchased on Amazon a portable monitor so that I could monitor the levels throughout the house. This monitor has shown the levels have remained in a safe amount also. When the old system wasnt working for several months, a quick 15-minute sampling had indicated a level of 6pCi/L.So, suffice it to say, the new system is working great!

Review 86 (2023-12-11 - Rating: 5)
Professional, quality work, communicated well, on schedule, low pressure sales, and good people.

Review 87 (2022-06-30 - Rating: 5)
Very helpful even though I didnt end up hiring them. Thats a sign of a good business

Review 88 (2023-06-12 - Rating: 5)
Best soil gas mitigation company in MD! Highly recommended!

Review 89 (2021-05-14 - Rating: 5)
Our experience with Radon Mitigation Services was excellent. From scheduling the appointments with Wendy to the quote and remediation by John and Tyler. Everyone was very professional and took the time to clearly explain the process, answer any questions along the way, and go over the entire project once the install was complete. The remediation included a radon test and results from a 3rd party company a few days after completion of the project. We would highly recommend Radon Mitigation Services.

Review 90 (2020-05-22 - Rating: 5)
High levels of radon in our home demanded a remediation effort. I met with Mike, the owner of the company last week, received a proposal that included a detailed design, specifications and a warranty at that same meeting. The contract cost, given the design that addressed my aesthetic concerns, was remarkably fair. The installation team of Patrick, Tyler and Clay arrived on schedule and set about their work without delay. The work was executed in a neat and workman like fashion and my wife and I could not be happier with the end result. In addition, all members of the team were polite, respectful and genuinely good guys. Two enthusiastic thumbs up and a recommendation that if radon mitigation is in your plans then give Mike and his company a call.

Review 91 (2020-04-28 - Rating: 5)
Our experience has been wonderful. The initial visit by John and Clayton provided us with an estimate for a new system. Patrick and Clayton returned today for our installation. We could not be happier with the end results. They were prompt, respectful and courteous throughout their visit. They answered any and all questions and explained all that was done and how the system functions. Thanks for your above and beyond work ethic and a job well done. To Wendy you were extremely pleasant and knowledgeable and made all the arrangements a breeze. Thanks, David Costigan

Review 92 (2017-11-02 - Rating: 5)
Everything was great! From my initial call to installation, everyone I dealt with was friendly and professional. The guys were on time and respected my home and cleanliness. Id recommend them without hesitation.

Review 93 (2020-06-18 - Rating: 5)
GMD is one of the best companies I have ever dealt with. They were knowledgeable in every aspect of radon and its mitigation. They were able to help me come up with a solution in a timely manner so we could go to settlement on our house. The gentlemen who cam to do the install were top notch and performed high quality work with a great explanation. I highly recommend GMD!

Review 94 (2018-03-16 - Rating: 5)
Our home had a very high radon reading and needed someone out immediately to activate our passive system. Radonworx got us scheduled very easily and quickly, I believe within 3 business days of me calling. Landon and Patrick came out to perform the job and were very friendly, professional and knowledgeable. I would highly recommend this company!

Review 95 (2020-07-22 - Rating: 5)
Company works quickly amd is very responsive. Tyler and Clayton were great installers - explained everything they did patiently and clearly. Left everything very clean. Would recommend them.

Review 96 (2018-02-07 - Rating: 5)
Mike Dietz and Radon Worx came highly recommended by one of our most trusted contractors National Water Service, and they lived up to the recommendation in every way. Mike tackled a very challenging house and managed to install a system that was unobtrusive and very effective, reducing our Radon to a negligible level. He was patient and expert in his assessment and recommendations, taking into consideration our desires as well as the need to adhere to code. We were so pleased with their work that we have hired them to do two more houses nearby. Highly Recommended.

Review 97 (2021-01-26 - Rating: 5)
GMD Radonworx did a fantastic job installing our remediation system today. They were punctual, affordable and left the work areas spotless. They are the ONLY company we consulted that drilled holes into the basement floor to gauge airflow as part of their evaluation of the space and our system needs. The install took about 4.5 hours and we could not be happier with how it turned out. GMD/Radonworx uses a 3rd party company to come and test the Radon levels a few days after installation.

Review 98 (2018-12-24 - Rating: 5)
Radonworx/ GMD Construction did an excellent job on our system. Very knowledgeable and professional. I would highly recommend them to anyone.

Review 99 (2020-02-25 - Rating: 5)
After doing 2 self tests for Radon I solicited 3 bids for a mitigation system. One was done strictly over the phone, sight unseen. With the other 2 a company representative came to the house and performed an inspection and made their recommendations for the system.Mike, with GMD, was the MOST thorough in his inspection and sat down with the 2 of us to explain what he proposed to do and how they would do it. Although his price was the highest, by only a SMALL margin, we felt GMD in the end provided the best value overall. Although the Radon levels were not awfully high to begin with (29cPi/L), the test after the work was done showed a mere 0.7cPi/L, WELL below the recommended 4.0cPi/L.GMD was ALWAYS on time and the work was completed in the timeframe predicted. The install is neat, compact, clean and very professional looking. I HIGHLY recommend GMD for your Radon Mitigation System