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Find Radon gas testers in Knoxville

Avatar for NextDay Inspect
NextDay Inspect
4.9(
348
)

Serving Knoxville, MD and surrounding areas

Approved

Super Service Award Winner

In business since 2008

Free estimates

Emergency services offered

"The structural/electrical/plumbing inspector was fantastic. He spent over 4 hours going through every inch of the home, provided immediate in-person feedback showing significant issues, and followed up <48 hours later (on a holiday weekend) with a 133-page report with pictures, thermal scans, etc. On a lesser note, the radon inspector showed for a few minutes during the structural inspection and set-up measurements in the basement. The report was issued quickly but I found out later that the radon inspector had not taken into consideration the attached (inaccessible) crawlspace that made up 25% of the lower structure. I found out from a radon remediation contractor that the state code required the radon inspector to measure levels on the 1st floor above the crawlspace in cases where the substructure could not be accessed. Overall, the huge amount of time the structural inspector put into the property was worth the A rating. Just watch the radon inspection if you have a strange basement set-up like the house I am purchasing."
Inspections with Matthew
Inspections with Larry
Inspections with Dimitri
Inspections with Rhonda
Cracks in the Foundation- Here we find moderate cracks in the foundation, with evidence that they've been repaired before.

+744

Response time8 hrs
Response rate99%
7 neighbors recently requested a quote
Avatar for JWH Inspections
JWH Inspections
5.0(
1
)

Serving Knoxville, MD and surrounding areas

Approved

In business since 2010

Free estimates

Credit card accepted

Hello my name is Jason William Hornung. Buying a home is a big investment. I want to help you make a well informed decision. I have been in the residential construction field for 17 years, and have an intimate knowledge of the homes in our area having done so much work in them myself. I stay continuously trained studying current information to give the best reports out there. I've seen many things that other inspectors have missed both as a home inspector and a contractor. My inspections meet or exceed the ASHI standards of practice. WWW.Homeinspector.org/standards WWW.JWHInspections.com

Home Inspection
Home Inspection
Home Inspection
Green Certified
Radon Certified

+3

Response time2 hrs
Response rate100%
Recommended by100%of homeowners
Avatar for Boston Environmental & Contracting, Inc
Boston Environmental & Contracting, Inc
4.4(
7
)

Serving Knoxville, MD and surrounding areas

Approved

In business since 2006

Free estimates

Credit card accepted

"We received an asbestos inspection/test for our old plaster walls and ceiling areas. The turn around times were fantastic - inspector was in our area and able to fit us in the same day I called. Sample results and accompanying lab report were emailed within 36 hours. All samples were analyzed by a local lab accredited under the NIST NVLAP Asbestos Fiber Analysis Lab Accreditation Program, so I felt comfortable trusting the results. The inspector seemed very knowledgeable and helped walk us through any areas that could be of concern. Thankfully all samples were negative, but the modest inspection and sampling fees were well worth the piece of mind during our remodel. In short, I highly recommend this company for asbestos testing/inspections."
5 neighbors recently requested a quote
Recommended by85%of homeowners
Avatar for Radon Experts of VA LLC
Radon Experts of VA LLC
5.0(
49
)

Serving Knoxville, MD and surrounding areas

In business since 2014

Free estimates

Emergency services offered

"Our existing system had been in the house 4 years and we had already had the fan replaced once. The previous company also used gutter pipe instead of PVC. We had Radon Experts come out to evaluate. Originally we were only going to replace the pipe since it was making so much noise that it was hard to sleep. Radon Experts told us that the type of fan that was being used was known for going bad and they recommended a different brand. It's been 3 months so far and no problem. They also replaced the pipe. They were quick efficient and very professional."
Recommended by100%of homeowners
Avatar for Inspections by Bob
Inspections by Bob
4.9(
145
)

Serving Knoxville, MD and surrounding areas

In business since 2003

Free estimates

Warranties offered

"<p>It is six months post-report.  He missed a lot of serious things.  Serious things that cost me a lot to fix. </p> <p>As one example, he noted on the report that the dishwasher light didn't work.  On day of final walkthrough, Seller had not fixed light.  Called Seller, she said it works, the light is just out and it is too cost prohibitive to fix  (a lie obviously).  First day in the house, I try to run it, it works for 15 minutes before error message appears.  Wrote Bob asking why he didn't tell me that it only worked for 15 minutes ---he said, well I told you the light was out, so I couldn't run a full cycle!  Um, how about saying in the report that the dishwasher DOES NOT OPERATE for more than 15 minutes AND the light is out.  That would have been good to know when negotiating with the Seller.  He said "go back to the Seller."  No, actually, I had a chance to inspect the property, I did, and you messed up.  Sure, the Seller is probably to blame, but come on, I would have to sue her to get my money!  Who has time for that?  That's the point of an inspection.  To avoid that. . . .$900 later. . . .</p> <p>Missed a huge crack in the oven heating element. . . .$900 later. . . .</p> <p>Nothing noted in the report about inadequate insulation.  Guess what? The insulation is inadequate.</p> <p>Missed several windows where the spring was broken.  Only noted a few.  </p> <p>Missed water damage.  Does not use infrared camera.</p> <p>He was never in the construction business before starting this business.  Ironically, he was in IT (see below).</p> <p>He pointed out a lot of things that weren't even an issue:  made a big deal about "exposed footings," hired an engineer to come out --who laughed---since Bob didn't seem to know what a footing is;  Bob said there is no deck flashing, when, yup, clearly there is.</p> <p>No excuse in this day and age not to have a computerized report with pictures in a pdf format.  He writes everything by hand and prints out separate pictures.  It took forever for him to finish the report while we all stood around.  Even the realtor was annoyed.</p> <p>He's a nice guy and he was prompt, I will give him that.  </p> <p>If I had to do it all over again, I would hire a bunch of experts for the same price I paid him.</p> <p>____________</p> <p>Response:</p> <p>Actually, the heating element worked.  The glass surrounding the heating element was cracked, thereby causing food to scorch because too much direct heat escaped, and also thermostat off.  </p> <p>Good to know that you had a piece of equipment you didn't think was useful to use because we didn't ask you to use it.  Since we're the home inspection experts?</p> <p>I have done two prior inspections with different inspectors, as well as sold my own homes.  Everyone else has a computerized report that is completed on-site.  Photos are uploaded digitally and integrated into the report.  The findings are discussed at the site.  Yes, I'm calling B.S.</p> <p>Now we're having issues with the HVAC.  Appears there is something wrong upstairs.  It was super dry in the winter (he does not do checks for Relative Humidity - FYI). Now air gets cold, but high humidity, probably something wrong with the ductwork or poor attic ventilation.  Great.  Another expense I wasn't expecting.  We noticed a musty smell in the home and asked Bob to check it out.  Bob said he smelled nothing.</p> <p>I didn't even mention the mold/mildew.  Which I actually hired him to test for.  Found nothing.  Turns out the swab method used by Bob isn't really all that great or diagnostic.  Terrific.</p> <p>Anyway, Bob, you're a super nice guy.  I hate to give you a negative review.  But that's what Angie's list is all about.  I hope you learn something from this.  Probably 99% of homes don't have major issues, but some do.  We count on you to guide us.  You failed.  And I don't think you even care that you did.<br /> <br /> <br /> <br /> <br /> <br /> <br /> <br /></p>"
Recommended by96%of homeowners
Avatar for The Home Detective
The Home Detective
4.9(
47
)

Serving Knoxville, MD and surrounding areas

In business since 1996

Free estimates

Emergency services offered

"Mr. Goldberg performed a radon test for me and did find that I had some moderate radon levels in my home. He's very efficient with what he does. He referred me to a guy named John Sweat to help me deal with the problem. I spoke with the guy and gave me a proposal but I have not heard from him in about a week and a half."
Recommended by97%of homeowners
Avatar for Kemp Home Inspections, LLC
Kemp Home Inspections, LLC
5.0(
49
)

Serving Knoxville, MD and surrounding areas

Free estimates

Warranties offered

"Beyond awesome...well the test results were bad but Greg was awesome. SUPER knowledgeable, communicative, and nice. I purchased the home, structural, mold, radon and termite inspections. One stop shopping. I HIGHLY recommend Greg for all of your inspection needs."
Recommended by100%of homeowners
Avatar for G M D Construction INC
G M D Construction INC
4.9(
98
)

Serving Knoxville, MD and surrounding areas

In business since 1985

Free estimates

Warranties offered

"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."
Recommended by98%of homeowners
BENNER GEOTECH
5.0(
16
)

Serving Knoxville, MD and surrounding areas

In business since 1998

Free estimates

Warranties offered

"We got their information from our friend. When we were making an appointment, Mike gave us his professional advice based on the house details. They arrived on time and Mike's team is extremely professional and friendly. They did a wonderful job for us. We are really impressed and pleased with their work. Will highly recommend anyone who wants to do radon mitigation."
Recommended by93%of homeowners
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FAQs for radon gas testing projects in Knoxville, MD

Radon is the second leading cause of lung cancer in the U.S. The gas seeps through cracks in foundations and collects in basements and other low areas. Once you breathe it in, radioactive particles lodge in lung tissue and do long-term damage. Because you can’t see or smell radon, the EPA recommends testing your home every two years—and after major renovations—to keep your family safe.

Yes—every home should be tested. The EPA advises doing it at least every two years and any time you remodel, buy, or sell. On average, one in 15 houses nationwide sits above the recommended limit, and the only way to know where yours stands is a formal test. The equipment simply measures gas levels and won’t change your indoor environment, so the process is completely harmless.

Certified radon professionals—often home inspectors or dedicated radon mitigation contractors—handle testing. These radon testing professionals follow EPA protocols and use calibrated instruments to check levels throughout your house. Hiring a certified radon specialist means results you can trust for real estate deals, insurance requirements, and, most importantly, your family’s health.

Inspectors specialize in measuring radon gas levels, while licensed mitigation contractors design and install the systems that remove it. If your test comes back high, your inspector can point you to a qualified mitigation pro who will size and install the right fan, piping, or other equipment to bring levels down.

No—standard home air purifiers don’t touch radon. They’re built to trap dust and pollen, not radioactive gas. If testing shows high levels, you’ll need a dedicated mitigation system that vents the gas from beneath your home to the outdoors. Relying on a room purifier alone won’t keep your indoor air safe.

Opening a few windows in your home might dilute radon for a short time, but the gas seeps back in as soon as they’re closed. For a lasting fix, you’ll need a professional mitigation system—often a sub-slab depressurization fan—that pulls radon from beneath the foundation and safely vents it outside.

The Knoxville, MD homeowners’ guide to radon gas testings

From average costs to expert advice, get all the answers you need to get your job done.