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Find Radon gas testers in Thornwood

Avatar for Lance Dorfi, LLC
Lance Dorfi, LLC
4.8(
59
)

Serving Thornwood, NY and surrounding areas

Approved

In business since 2010

Free estimates

Emergency services offered

"I value expertise and we are working together to find the source of the radon readings and will discuss remediation after the next test results."
Job Site
Response time2 days
28 neighbors recently requested a quote
Recommended by96%of homeowners
Avatar for JCL Home Inspections
JCL Home Inspections
4.9(
26
)

Serving Thornwood, NY and surrounding areas

Approved

In business since 2015

Free estimates

Customers say: Quick response

"The professionalism and price was great! Joe issued the home inspection report in a timely fashion and it was very well done and thorough."
Response time4 hrs
3 neighbors recently requested a quote
Recommended by100%of homeowners
Avatar for Doctor House Inspections, LLC
Doctor House Inspections, LLC
4.9(
8
)

Serving Thornwood, NY and surrounding areas

Approved

In business since 2014

Customers say: Quick response

"Olivier is extraordinarily thorough in h=is inspection and report. No stone was left unturned, and his report was extensive, detailed, and clear. He is committed to doing his best for his customers and giving them the best sense of the home they are about to potentially purchase. I can't imagine a better guide through this part of the home-buying process. His work was invaluable to us."
Deck issues
Oil line in concrete slab
Rusted oil tank
A boiler with a direct hot water heater
Loose electrical service entrance wire

+18

Response time4 hrs
Response rate100%
Recommended by100%of homeowners
Avatar for Phase 1 Restoration Inc.
Phase 1 Restoration Inc.
4.8(
19
)

Serving Thornwood, NY and surrounding areas

Approved

In business since 1987

Free estimates

Emergency services offered

"The rep came out and reviewed the areas of concern.  He gave me an estimate on the spot. The next day I decided to go with JBH and the project was scheduled for the following week.  The workers arrived within the scheduled time period and they were very pleasant to work with. They were responsive, efficient and neat. The job was completed in no time. <br />"
Additional Photos
Response time2 days
1 neighbors recently requested a quote
Recommended by89%of homeowners
Essential Home Services, LLC
5.0(
9
)

Serving Thornwood, NY and surrounding areas

Approved

Super Service Award Winner

In business since 2000

Free estimates

Credit card accepted

is committed to excellence in every aspect of our business. We uphold a standard of integrity bound by fairness, honesty, and personal responsibility. Our distinction is the quality of service we bring to our customers. Accurate knowledge of our trade combined with ability is what makes us true professionals. Above all, we are watchful of our customers' interests and make their concerns the basis of our business.\n

Response time6 hrs
39 neighbors recently requested a quote
Recommended by11%of homeowners
Oakhill Home Inspections
5.0(
1
)

Serving Thornwood, NY and surrounding areas

Approved

In business since 2025

Free estimates

Emergency services offered

I pride my company on reliability, great communication, integrity, and quality work. I am an expert in home inspections, mold testing and radon testing and remediation. I will do my absolute best to keep you as educated and informed on your particular inspection project. I look forward to earning your business! Book with me online or feel free to give me a call today! My focus is protecting your home investment.\n\nThank You,\nCharles Rauch\nOakhill Home Inspections

Response time5 hrs
12 neighbors recently requested a quote
Power House Inspection LLC
New to Angi

Serving Thornwood, NY and surrounding areas

Approved

In business since 2024

Free estimates

Emergency services offered

We invite you to experience a tradition of customer satisfaction that will exceed your greatest expectations. Our professionalism and quality workmanship will accurately reflect your taste and lifestyle. From conception to completion, we work with you until the job is done. We are ethical, honest, and easy to communicate with. \n\nCall us today you'll be pleased you did. Thank you

4 neighbors recently requested a quote
Avatar for Poseidon Home Inspections LLC
Poseidon Home Inspections LLC
5.0(
99
)

Serving Thornwood, NY and surrounding areas

In business since 2009

Free estimates

Warranties offered

"I would recommend Poseidon Home Inspections to anyone looking at property in Westchester. Andy was excellent and very thorough. He has clearly been deeply involved at all levels of house ownership which truest shows through in his work. Especially as a first time home buyer, Andy will reveal any and all details about the house you need to know about. Even my realtor was blown away by his level of detail and care. Cannot recommend Poseidon Home Inspections enough. This service was expensive, but wow, was it worth it. We now have a 5-10year financial plan for home upgrades and maintenance which aligns to all the inspection findings."
Recommended by100%of homeowners
Avatar for Northeast Mitigation Services
Northeast Mitigation Services
4.9(
80
)

Serving Thornwood, NY and surrounding areas

In business since 2005

Free estimates

Emergency services offered

"Amazing! Fernando was really helpful. He looked at our job, and helped us navigate an erroneous elevated radon level due to the weather. He saved us in a situation where we would have spent a thousand without solving anything. Thank you. Your guidance and engagement was very helpful."
Recommended by96%of homeowners
Avatar for Above Grade Home Inspections Inc
Above Grade Home Inspections Inc
5.0(
287
)

Serving Thornwood, NY and surrounding areas

In business since 1998

Free estimates

Warranties offered

"House: Mid 1800s farmhouse, approximately 4000 square feet Inspection Components: General home inspection, plus termite, radon, well water, and septic tests Time to complete: approximately 3 hours. Inspection report was provided the same day and other tests came in a week and a half later. Inspector (Chuck): Was responsive and and accommodating for scheduling the inspection. He arrived early on the day of inspection to begin his prep work. Chuck took his time to explain the inspection process and walk us through each part of the home. He gave us detailed overviews of similar homes and potential issues, then explained how this home compared. He also helped explain how the mechanics of the house work and how to operate components of it effectively. Quality: As far as we can tell, Chuck's inspection was very thorough. He pointed out a number of issues and look his time to triage and assess potential problems. His equipment is top notch, and includes a drone for roof shots and a thermal camera for assessing the heating system and finding heat leaks. He collaborated well with a second septic inspector we had on site and even found a minor plumbing leak in the basement that had previously been undetected. Value: For the size of this home and quality of his service, Chuck was a great value. His price includes a discount for finding him via Angie's List. Summary: I recommend Chuck based on his service. Chuck arrived early, was detail oriented, and provided a high quality report. Other reviews on Angie's List seem to be accurate reflections of his work. I did have to send him a reminder e-mail to get our well and radon results although Chuck responded back with the results very quickly. This was around the holidays so, considering, that minor delay was understandable and not a big deal."
Recommended by98%of homeowners
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FAQs for radon gas testing projects in Thornwood, NY

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 Thornwood, NY homeowners’ guide to radon gas testings

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