Older homes can contain asbestos and lead-based paint, and any home can have high radon. Homes with drywall installed from 2001 to 2009 may have what the U.S. Consumer Product Safety Commission (CPSC) calls problem drywall. Fuel-burning appliances can release carbon monoxide (CO). The Environmental Protection Agency (EPA) says you usually cannot identify asbestos by sight, so testing is done by trained professionals.
Last reviewed: September 2026. Sources are listed at the end of this page.
Which hazards should you look for in an older home?
Five hazards come up most often in federal guidance. The table compares where each one shows up and who handles it.
| Hazard | Where it shows up | Who tests or fixes it |
|---|---|---|
| Asbestos | Vermiculite attic insulation, vinyl floor tiles and backing, roofing and siding shingles, textured paint, pipe and furnace insulation[1] | A trained and accredited asbestos professional[2] |
| Lead-based paint | Homes built before 1978, especially windows, doors, stairs and porches[6] | A certified lead inspector or risk assessor[12] |
| Radon | Soil gas entering through cracks, joints and gaps around pipes[17] | A home test, then a qualified radon mitigation contractor if needed[17] |
| Problem drywall | Drywall installed from 2001 to 2009[21] | Follow CPSC identification and remediation guidance[22] |
| Carbon monoxide | Furnaces, water heaters, gas stoves, fireplaces, generators, attached garages[23] | A trained professional for yearly heating system service[23] |
How do you know if your home has asbestos?
You usually cannot tell by looking. EPA says a material cannot be identified as asbestos by sight unless it is labeled.[2] EPA does not recommend taking samples yourself. A trained and accredited asbestos professional should take them.[2]
EPA advises leaving undamaged asbestos material alone. Repair means sealing it (encapsulation) or covering it (enclosure). Removal is complex and only a trained and accredited professional should do it, because improper removal can raise your exposure.[2]
Watch for vermiculite attic insulation. EPA says a mine near Libby, Montana, supplied over 70 percent of U.S. vermiculite from 1919 to 1990 and was contaminated with asbestos. It was often sold as Zonolite and looks pebble-like, gray-brown or silver-gold. EPA says to assume it contains asbestos and not disturb it.[4]
EPA links asbestos to lung cancer, mesothelioma and asbestosis.[1] The National Cancer Institute (NCI) says symptoms can take 10 to 40 years or more to appear, and smokers exposed to asbestos face a combined lung cancer risk greater than the two risks added together.[3] EPA’s asbestos air toxics rule (NESHAP) excludes residential buildings with four or fewer units.[5]
Does a home built before 1978 have lead-based paint?
It is more likely to. EPA says the federal government banned consumer uses of lead-based paint in 1978.[6] Paint that is peeling, chipping, chalking, cracking or damp is a hazard that needs immediate attention. Scraping, sanding or heating lead paint during repairs can create lead dust, even in a well-kept home.[6]
CDC (the Centers for Disease Control and Prevention) says no safe blood lead level in children has been identified. Children under 6 face more exposure because of hand-to-mouth behavior, and the effects can be permanent.[11]
- Contractors: EPA’s Renovation, Repair and Painting (RRP) Rule requires anyone paid to disturb paint in pre-1978 homes to be certified and trained in lead-safe practices.[7][8] It does not apply to homeowners working on their own homes, unless they rent the home out, run a childcare center there, or renovate homes to sell for profit.[7]
- Buying or renting: sellers and landlords of most pre-1978 housing must disclose known lead paint, provide available records and the pamphlet Protect Your Family From Lead in Your Home, and offer buyers a 10-day period for a paint inspection or risk assessment.[9][10]
- Testing: an inspection finds where lead paint is. A risk assessment finds lead hazards in paint, dust and soil. EPA says to hire a certified inspector or risk assessor, or assume the home has lead paint.[12][13]
Should you test your home for radon?
Yes. EPA and the Surgeon General recommend testing all homes below the third floor.[17] Radon is a radioactive gas that forms when uranium, thorium or radium break down in rock, soil and groundwater. You cannot see, smell or taste it.[14][17]
EPA estimates radon causes about 21,000 lung cancer deaths each year. It is the leading cause of lung cancer among non-smokers and the second leading cause overall.[15] EPA estimates nearly 1 in 15 U.S. homes has elevated levels.[17]
- Action level: fix the home at 4 picocuries per liter (pCi/L) or more. Consider fixing between 2 and 4 pCi/L.[15][16]
- Tests: short-term tests last 2 to 90 days. Long-term tests last more than 90 days.[17]
- Zone map: EPA says its radon zone map should not be used to decide whether to test a single home. Test no matter where you live.[16]
- Fixing it: active subslab suction (subslab depressurization) is the most common and usually most reliable method. Retest within 30 days of installation, but no sooner than 24 hours after the system starts.[18]
EPA lists every state radon program, with contacts, on its radon zones supplemental information page.[19]
What is problem drywall?
Problem drywall is CPSC’s term for drywall linked to hydrogen sulfide gas and corrosion in homes. It is widely called “Chinese drywall.” CPSC-funded studies found a strong association between problem drywall, hydrogen sulfide and corrosion.[20]
The main sign is blackened copper electrical wiring or air conditioning evaporator coils in a home with drywall installed from 2001 to 2009. Confirming evidence includes elemental sulfur in the drywall core, Chinese markings and elevated sulfide gas emissions.[21]
CPSC’s investigation began in early 2009 and included the Department of Housing and Urban Development (HUD), CDC and EPA.[20] CPSC now reports about 4,051 reports from 44 states, the District of Columbia, American Samoa and Puerto Rico, mostly in homes built in 2006 and 2007. CPSC says it has completed its investigation.[24]
CPSC’s remediation guidance calls for replacing all problem drywall, smoke and CO alarms, electrical distribution components and fusible sprinkler heads.[22] Studies by the National Institute of Standards and Technology (NIST) in 2011 found no evidence of a substantial safety hazard from corrosion in smoke alarms, sprinkler heads or gas piping.[22]
How do you protect your home from carbon monoxide?
Install CO alarms and have fuel-burning equipment serviced every year. CPSC describes CO as a colorless, odorless, poisonous gas.[25]
The two federal death counts measure different things, so read them separately:
- CPSC: more than 200 people in the U.S. die each year from accidental non-fire CO poisoning associated with consumer products.[25]
- CDC: more than 400 Americans die each year from all unintentional CO poisoning not linked to fires. More than 100,000 visit an emergency department and more than 14,000 are hospitalized.[26]
CPSC says to put battery or battery-backup CO alarms on every level and outside sleeping areas.[25] CDC advises checking batteries each spring and fall and never running a generator inside your home or garage, even with doors and windows open.[26] EPA recommends a yearly professional inspection of furnaces, flues and chimneys.[23] CDC lists headache, dizziness, weakness, upset stomach, vomiting, chest pain and confusion as symptoms.[26]
This page is general information, not medical advice. If you have health concerns, talk to your doctor. Have a qualified, certified professional test and assess your home.
Related guides
- What a standard home inspection leaves out
- Mold after water intrusion
- What counts as a construction defect
- How to document a construction defect
Sources
- U.S. Environmental Protection Agency, “Learn About Asbestos,” last updated July 13, 2026.
- U.S. Environmental Protection Agency, “Protect Your Family from Exposures to Asbestos,” last updated June 25, 2026.
- National Cancer Institute, “Asbestos Exposure and Cancer Risk Fact Sheet,” reviewed May 20, 2021.
- U.S. Environmental Protection Agency, “Protect Your Family from Asbestos-Contaminated Vermiculite Insulation,” last updated April 17, 2026.
- U.S. Environmental Protection Agency, “Asbestos National Emission Standards for Hazardous Air Pollutants (NESHAP),” last updated December 22, 2025.
- U.S. Environmental Protection Agency, “Protect Your Family from Sources of Lead,” updated June 15, 2026.
- U.S. Environmental Protection Agency, “Lead Renovation, Repair and Painting Program,” last updated June 17, 2026.
- U.S. Environmental Protection Agency, “Lead Renovation, Repair and Painting Program Rules,” no date shown.
- U.S. Environmental Protection Agency, “Lead-Based Paint Disclosure Rule (Section 1018 of Title X),” last updated December 4, 2025.
- U.S. Environmental Protection Agency, “Real Estate Disclosures about Potential Lead Hazards,” last updated May 27, 2026.
- Centers for Disease Control and Prevention, “About Childhood Lead Poisoning Prevention,” August 21, 2025.
- U.S. Environmental Protection Agency, “Questions and Answers for Homeowners and Renters about Understanding Lead Inspections, Risk Assessments and Abatements,” last updated May 27, 2026.
- U.S. Environmental Protection Agency, “Reduce the Risk of Lead Exposure at Home,” last updated August 19, 2026.
- U.S. Environmental Protection Agency, “What is Radon?,” updated September 16, 2026.
- U.S. Environmental Protection Agency, “Health Risk of Radon,” updated June 24, 2026.
- U.S. Environmental Protection Agency, “The EPA Map of Radon Zones,” last updated August 17, 2026.
- U.S. Environmental Protection Agency, “A Citizen’s Guide to Radon,” EPA402/K-12/002.
- U.S. Environmental Protection Agency, “Consumer’s Guide to Radon Reduction: How to Fix Your Home,” EPA 402/K-10/005.
- U.S. Environmental Protection Agency, “EPA Map of Radon Zones and Supplemental Information,” last modified August 26, 2026.
- U.S. Consumer Product Safety Commission, “Interagency Drywall Investigation,” no date shown.
- U.S. Consumer Product Safety Commission, “How Can I Tell If My Home Has Problem Drywall?,” no date shown.
- U.S. Consumer Product Safety Commission, “CPSC Completes Final Studies to Help Affected Homeowners Remediate Problem Drywall,” September 15, 2011.
- U.S. Environmental Protection Agency, “Carbon Monoxide’s Impact on Indoor Air Quality,” last updated July 15, 2026.
- U.S. Consumer Product Safety Commission, “Drywall Information Center,” no date shown.
- U.S. Consumer Product Safety Commission, “Carbon Monoxide Information Center,” 2026.
- Centers for Disease Control and Prevention, “Carbon Monoxide Poisoning,” January 12, 2026.