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G M D Construction INC

Wells and Pumps, Water & Smoke Damage, Radon Detection & Reduction

About us

National Environmental Health Association #100026. National Radon Safety Board 248G. EPA RCCP 10032. DBA: Radon Mitigation Services.

Business highlights

40 years of trusted experience

Services we offer

Radon mitigation, basement/ crawl space/ block wall de-humidification, multi-family, new construction

Amenities

Free Estimates
Yes


Accepted payment methods

Check

Photos of past projects

Reviews

4.9102 Reviews
Number of StarsImage of DistributionNumber of Ratings
5
94%
4
2%
3
0%
2
4%
1
0%


Rating CategoryRating out of 5
quality
5.0
value
4.9
professionalism
4.9
responsiveness
5.0
punctuality
5.0
Showing 1-25 of 102 reviews

Mark T.
12/2020
5.0
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.
Description of Work: Radon mitigation in 17 year old house

Rating CategoryRating out of 5
quality
5.0
value
5.0
professionalism
5.0
responsiveness
5.0
punctuality
5.0

Yes, I recommend this pro
$1,350

Allen S.
09/2020
5.0
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.
Description of Work: Radon mitigation

Rating CategoryRating out of 5
quality
5.0
value
5.0
professionalism
5.0
responsiveness
5.0
punctuality
5.0

Yes, I recommend this pro
$1,700

Anne L.
02/2019
5.0
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.
Description of Work: Radon Remediation

Rating CategoryRating out of 5
quality
5.0
value
5.0
professionalism
5.0
responsiveness
5.0
punctuality
5.0

Yes, I recommend this pro
$1,100

Cherie M.
02/2019
5.0
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.
Description of Work: Radon Remediation

Rating CategoryRating out of 5
quality
5.0
value
5.0
professionalism
5.0
responsiveness
5.0
punctuality
5.0

Yes, I recommend this pro
$1,200

Steven H.
08/2018
5.0
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.
Description of Work: Update existing radon system to vent through attic and roof.

Rating CategoryRating out of 5
quality
5.0
value
5.0
professionalism
5.0
responsiveness
5.0
punctuality
5.0

Yes, I recommend this pro
$875

Carl E.
07/2018
5.0
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.
Description of Work: Radon Evaluation and Mitigation

Rating CategoryRating out of 5
quality
5.0
value
4.0
professionalism
5.0
responsiveness
5.0
punctuality
5.0

Yes, I recommend this pro
$1,850

Sharon H.
03/2018
5.0
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.
Description of Work: Vent stack and fan replacement

Rating CategoryRating out of 5
quality
5.0
value
5.0
professionalism
5.0
responsiveness
5.0
punctuality
5.0

Yes, I recommend this pro
$475

Marty G.
03/2018
2.0
This was bad. They came to provide an estimate, never followed up, and then stopped responding to emails entirely. This was probably for the best, because they wanted to sell me a complicated, overpriced setup that wasn't even necessary. If they didn't want to do the work, they could have just told me that instead of ghosting me. Total waste of time.
Description of Work: Radon mitigation

Rating CategoryRating out of 5
professionalism
3.0
responsiveness
1.0
punctuality
5.0


Response from G M D Construction INC
[Member Name Removed], We have no record of you in our data base, or any emails with your name attached to them... Are you sure you have the correct company???

Karma L.
01/2018
5.0
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.
Description of Work: Activate a passive radon mitigation system, and a little basement sealing

Rating CategoryRating out of 5
quality
5.0
value
5.0
professionalism
5.0
responsiveness
5.0
punctuality
5.0

Yes, I recommend this pro
$650

Arsalan S.
01/2018
5.0
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.
Description of Work: Radon testing and remediation

Rating CategoryRating out of 5
quality
5.0
value
5.0
professionalism
5.0
responsiveness
5.0
punctuality
5.0

Yes, I recommend this pro
$1,200

Andrew S.
01/2018
5.0
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.
Description of Work: Radon Mitigation

Rating CategoryRating out of 5
quality
5.0
value
5.0
professionalism
5.0
responsiveness
5.0
punctuality
5.0

Yes, I recommend this pro
$1,800

Nicholaus K.
11/2017
5.0
Their work was top notch, very professional. I am very pleased with the quality of the system they installed.
Description of Work: They installed a radon remediation system.

Rating CategoryRating out of 5
quality
5.0
value
5.0
professionalism
5.0
responsiveness
5.0
punctuality
5.0

Yes, I recommend this pro
$1,300

Jean H.
10/2017
5.0
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.
Description of Work: We needed a radon remediation system. Mike explained everything we needed to know. We had other issues with the basement not related to radon and he explained what the likey cause was.

Rating CategoryRating out of 5
quality
5.0
value
5.0
professionalism
5.0
responsiveness
5.0
punctuality
5.0

Yes, I recommend this pro
$1,000

Louis S.
09/2017
5.0
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.
Description of Work: We had a radon mitigation system installed.

Rating CategoryRating out of 5
quality
5.0
value
5.0
professionalism
5.0
responsiveness
5.0
punctuality
5.0

Yes, I recommend this pro
$1,300

Amanda H.
09/2017
5.0
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.
Description of Work: We had a Radon remediation system installed. Actually ended up needing 2 systems due to a concrete slab foundation under an in-law suite behind the garage. As well as a new sump pump which needed to be replaced before they sealed off the pit.

Rating CategoryRating out of 5
quality
5.0
value
5.0
professionalism
5.0
responsiveness
5.0
punctuality
5.0

Yes, I recommend this pro
$2,000

Jonathan A.
09/2017
5.0
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.
Description of Work: They came out and inspected my radon reduction system to make sure it was working.

Rating CategoryRating out of 5
quality
5.0
value
4.0
professionalism
5.0
responsiveness
5.0

Yes, I recommend this pro
$115

Archana D.
09/2017
5.0
They were excellent. Arrived ahead of time and got the work done most efficiently.
Description of Work: Installation of radon mitigation system

Rating CategoryRating out of 5
quality
5.0
value
5.0
professionalism
5.0
responsiveness
5.0
punctuality
5.0

Yes, I recommend this pro

Teresa B.
09/2017
2.0
I called this company based on the many "A" plus reviews. Also, via word of mouth. The person arrived at my house at 12:30 pm for a 1:30 pm appointment. I got home about 1:00ish to prepare for the 1:30 pm arrival. The person seemed frustrated because he had been sitting there since 12:30 pm for a 1:30 pm appt. He seemed frustrated the entire time going through my house talking to himself. When he needed to get to another spot I offered to move things such as a laundry basket (small things) etc. He would said no frustratingly and walk away. I also offered to cut a piece of the wall and floor out because his biggest complaint was that my house was complicated and that it was finished. He even mentioned that the the dining room was finished with frustration because he was trying to look where the furnace went. Yep my dining is finished. Again, I offered to cut a piece of the wall out in the basement and the floor mentioning we do not mind at all as it is important for the health of our family. Something we plan on replacing any way in the future. At the end of his surveying of the house he slams his book down on my kitchen table and says my house is too complicated he is not giving me a quote. At this time I have to speak up and state that I do not like the way he is talking to me and treating me. He claims his frustration was on the house and not me. But as I continue to ask questions to understand I felt like he was responding the way he was because I am a women. My 12 year old daughter was shocked when he left as she commented on how he spoke to me and how he slammed his binder down on our table. So it wasn't just me. We are getting a mitigation system as we know what are levels were previously from home inspection and it was suggestion to have a system installed. I wasted an afternoon of work. Now back to searching for companies.
Description of Work: No work completed

Rating CategoryRating out of 5
professionalism
2.0
responsiveness
2.0
punctuality
2.0


Response from G M D Construction INC
Mrs. [Member Name Removed], Yes arrived early and was very happy to wait as I was catching up on paperwork, and yes as I mentioned while there I was flustered with your house. My job as a radon mitigator is not only to repair the radon issue but to do it in a [Member Information Removed] that does not cause other potential issues within the property and to try to blend everything in as much as possible to prevent eye sores. In your house I have two foundations, the lower is beautifully finished with a very nice wood floor that is covering a sump pit. Due to the location of said sump pit and the lay of the land I have to believe the basement has flooded more than once and that there probably is waterproofing behind your finished walls. If I was to install a suction system on that slab without sealing the waterproofing (if its there) and the sump pit this very easily could back draft your furnace and water heater ( cause the exhaust fumes to come into the house and possible carbon monoxide) which could be very DANGEROUS. The house may require a 2nd system on the old sun room slab that is now a family room and kitchen. In the effort to better evaluate the property I recommended to you to do additional testing and that the wood floor needs to be partially removed in the finished area. I also gave you an online place to get Do It Yourself test kits in quantity to try and save you money. I would be most happy to come back out once the floor is opened and you do the additional testing. I would like the four corners of the basement tested all at the same time. Lastly, Safety always come first, energy conservation second, and ascetics third. Thanks, Mike

Bruce M.
08/2017
5.0
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.
Description of Work: I had a radon test conducted in my basement and the reading was high enough to warrant putting in a remediation system. I was aware of the potential dangers of radon and I did research on the best way to address it.

Rating CategoryRating out of 5
quality
5.0
value
5.0
professionalism
5.0
responsiveness
5.0
punctuality
5.0

Yes, I recommend this pro
$1,800

Guy R.
07/2017
5.0
wells
  + -1 more
Work was performed well for a fair price. I would hire again!
Description of Work: Radon mitigation and a new sump pump.

Rating CategoryRating out of 5
quality
5.0
value
5.0
professionalism
5.0
responsiveness
5.0
punctuality
5.0

Yes, I recommend this pro
$900

John G.
06/2017
4.0
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.
Description of Work: Activation of a passive radon reduction system.

Rating CategoryRating out of 5
quality
4.0
value
5.0
professionalism
5.0
responsiveness
5.0
punctuality
5.0

Yes, I recommend this pro
$850

Linda T.
06/2017
5.0
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.
Description of Work: Radon mediation

Rating CategoryRating out of 5
quality
5.0
value
5.0
professionalism
5.0
responsiveness
5.0
punctuality
5.0

Yes, I recommend this pro
$750

Kathy B.
06/2017
5.0
He was professional, courteous and on time.
Description of Work: Radiation hookup was incorrect by previous homeowners and GMD corrected it. The outside pipe wasn't ventilating above roof line but to the under eaves of the house.

Rating CategoryRating out of 5
quality
5.0
value
5.0
professionalism
5.0
responsiveness
5.0
punctuality
5.0

Yes, I recommend this pro
$350

Mary T.
05/2017
5.0
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.
Description of Work: Radon mitigation services.

Rating CategoryRating out of 5
quality
5.0
value
5.0
professionalism
5.0
responsiveness
5.0
punctuality
5.0

Yes, I recommend this pro
$1,000

Jean K.
05/2017
5.0
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.
Description of Work: Radon system install, including new sump pump

Rating CategoryRating out of 5
quality
5.0
value
5.0
professionalism
5.0
responsiveness
5.0
punctuality
5.0

Yes, I recommend this pro

Contact information

17530B Frederick Rd, Mount Airy, MD 21771

http://www.radonworx.com

Service hours

Monday:
7:00 AM - 7:00 PM
Tuesday:
7:00 AM - 7:00 PM
Wednesday:
7:00 AM - 7:00 PM
Thursday:
7:00 AM - 7:00 PM
Friday:
7:00 AM - 7:00 PM

Licensing

Bonded

Insured
State Contractor License Requirements

All statements concerning insurance, licenses, and bonds are informational only, and are self-reported. Since insurance, licenses and bonds can expire and can be cancelled, homeowners should always check such information for themselves. To find more licensing information for your state, visit our State Contractor License Requirements page.

*Contact business to see additional licenses.


Service Categories

Wells and Pumps,
Water & Smoke Damage,
Radon Detection & Reduction

FAQ

G M D Construction INC is currently rated 4.9 overall out of 5.

Monday: 7:00 AM - 7:00 PM

Tuesday: 7:00 AM - 7:00 PM

Wednesday: 7:00 AM - 7:00 PM

Thursday: 7:00 AM - 7:00 PM

Friday: 7:00 AM - 7:00 PM

G M D Construction INC accepts the following forms of payment: Check
Yes, G M D Construction INC offers free project estimates.
No, G M D Construction INC does not offer eco-friendly accreditations.
No, G M D Construction INC does not offer a senior discount.
No, G M D Construction INC does not offer emergency services.
No, G M D Construction INC does not offer warranties.
G M D Construction INC offers the following services: Radon mitigation, basement/ crawl space/ block wall de-humidification, multi-family, new construction

Contact information

17530B Frederick Rd, Mount Airy, MD 21771

http://www.radonworx.com

Service hours

Monday:
7:00 AM - 7:00 PM
Tuesday:
7:00 AM - 7:00 PM
Wednesday:
7:00 AM - 7:00 PM
Thursday:
7:00 AM - 7:00 PM
Friday:
7:00 AM - 7:00 PM