The doctor says your child has asthma. The headaches keep coming back and you can't explain them. The house feels stuffy in winter no matter how long you run the furnace. These aren't random complaints. In Detroit's older housing stock, they often have a physical cause — and it's usually inside the walls, under the floor, or coming out of a pipe.
Most of Detroit's homes were built before 1960. That matters because the standards governing indoor air, ventilation, and building materials have changed dramatically since then. What those older homes were built with — and what they weren't built with — creates a specific set of indoor hazards that deserve a straight answer.
This article covers four of them: radon, carbon monoxide, lead paint, and asthma triggers. Each one is common in older homes, each one carries real health consequences, and each one is addressable.
Why Detroit's Older Housing Stock Creates Indoor Air Problems
Older homes were built tight for winter and loose by modern standards everywhere else. There were no vapor barriers, no mechanical ventilation requirements, and no combustion safety protocols built into the design. Combustion appliances vented through masonry chimneys that have had sixty or seventy years to develop cracks. Foundation walls and floor slabs have had the same amount of time to develop the gaps that let soil gases in.
Winter makes it worse. When a house is buttoned up against Michigan cold, whatever is in the air stays there. Combustion byproducts, moisture, particulates from aging materials — they accumulate because there's nowhere for them to go. The problem isn't that Detroit homeowners are doing anything wrong. The problem is that the house itself is generating hazards that ventilation and modern construction would have controlled.
Radon: The Invisible Hazard Under the Floor
Radon is a radioactive gas that forms naturally when uranium in soil and rock breaks down. It enters homes through cracks in foundation walls and slabs, gaps around pipes, and floor drains. You can't smell it, see it, or taste it.
Approximately 1 in 4 Michigan homes has radon levels at or above the EPA action level of 4 picocuries per liter (pCi/L). Elevated levels have been detected in all 83 Michigan counties. (Source: Michigan EGLE Indoor Radon Program; Michigan Governor's January 2026 Radon Action Month proclamation, michigan.gov.)
The health consequence is serious: radon is the leading cause of lung cancer among nonsmokers and the second leading cause overall. (Source: EPA Health Risk of Radon page, epa.gov/radon/health-risk-radon.)
Older homes are at higher risk. Foundation walls and slabs develop more cracks over decades, and construction from that era rarely included radon-resistant techniques — sealed vapor barriers, sub-slab depressurization systems, or properly sealed penetrations.
Michigan homes, including those in Detroit and Highland Park, fall into this risk profile. The only way to know your home's radon level is to test it. EGLE's Indoor Radon Program offers low-cost test kits and information at 800-RADON-GAS (michigan.gov/egle, search "Indoor Radon Program").
Carbon Monoxide: What Happens When Furnaces and Water Heaters Age
A furnace that worked fine for twenty years can become a carbon monoxide source in its twenty-first. When heat exchangers crack, flues corrode, or chimneys block, the combustion gases that should exit the house re-enter the living space instead. That process is called backdrafting, and it's more common in older homes because the equipment and the flues are older.
Faulty furnaces and improperly vented appliances are among the most common sources of carbon monoxide exposure in Michigan homes. (Source: MDHHS November 2024 CO safety reminder, michigan.gov/mdhhs.) Michigan data bears this out: furnaces were the source in roughly 1 in 5 Michigan CO poisoning hospitalizations and emergency department visits from 2009 to 2014 — 1,037 of 5,217 cases. (Source: stacks.cdc.gov/view/cdc/231078.)
Carbon monoxide poisoning symptoms — headaches, fatigue, nausea, dizziness — are frequently confused with the flu. That's part of what makes CO exposure in older homes dangerous: it often goes unrecognized for extended periods while the source continues operating. Children and people with cardiovascular conditions are especially vulnerable to low-level chronic exposure.
Installing CO detectors on every level of the home is the minimum step. A combustion safety assessment — checking heat exchangers, flue connections, and appliance venting — is the diagnostic step that tells you whether the equipment itself is the problem. That assessment is a core part of a healthy-home evaluation.
Lead Paint: The Pre-1978 Baseline Risk
Federal law banned residential lead-based paint in 1978. Any home built before that year may contain it. (Source: EPA Lead-Based Paint Disclosure Rule, epa.gov/lead.)
The scale of the remaining exposure risk is documented: 34.6 million U.S. homes — 29.4% of all housing units — still contain lead-based paint. The likelihood is highest in homes built before 1940. (Source: HUD American Healthy Homes Survey II, cited by EPA at epa.gov/lead.)
For children, lead exposure impairs brain development and is linked to lower IQ, learning problems, delayed growth, and behavioral issues. No safe level of lead exposure has been established for children. (Source: EPA and CDC.)
Intact lead paint on an undisturbed surface poses lower immediate risk. The hazard increases sharply when paint deteriorates — blistering, peeling, chalking — or when renovation work creates dust. Detroit's aging housing stock has both: surfaces that have been deteriorating for decades, and homes that need repair work. Those two conditions together are where childhood lead exposure often begins.
Homeowners in pre-1978 homes should have a certified inspector assess lead paint condition before starting any renovation. WWGT's Healthy Home Production program addresses lead paint condition as part of its whole-home assessment scope.
Asthma Triggers: Mold, Moisture, Pests, and What Detroit's Data Shows
Detroit's childhood asthma rate is not comparable to Michigan's overall. Childhood asthma prevalence in Detroit is 14.6%, compared to 8.4% for Michigan as a whole. Detroit residents were hospitalized for asthma at least four times more than Michigan residents overall during the same period (2016–2019 data). (Source: MDHHS Detroit Asthma Burden 2021 report.)
Those numbers reflect what older housing does when it isn't maintained or repaired: moisture gets in, mold grows, pests find entry points, and poor ventilation keeps particulates concentrated at levels that healthy homes don't reach.
The common indoor asthma triggers in Detroit's older homes include mold from moisture intrusion, cockroach allergens, dust mites in aging carpet and soft furnishings, combustion particles from older furnaces, and indoor air that concentrates fine particulates because there's no mechanical ventilation to dilute them. (Source: EPA Asthma Triggers page, epa.gov/asthma.)
A 2014 study of Detroit children with asthma living near major roadways — the NEXUS near-road air pollution study (PMC4241249, n=112 homes) — found ERMI values in floor dust samples averaged 14.5, a level indicating high mold contamination.
The physical conditions drive the clinical outcomes. Fix the moisture intrusion, seal the pest entry points, improve ventilation, and the trigger load drops. That's the connection between housing condition and asthma hospitalizations, and it's the logic behind what a healthy-home program actually does.
What a Healthy Home Assessment Actually Covers
WWGT's Healthy Home Production program looks at the full stack of indoor hazards, not just energy performance.
A healthy-home assessment covers radon risk pathways, combustion safety, moisture and ventilation, lead paint condition, pest entry points, and indoor air flow. It's distinct from a standard home energy audit, which focuses on energy losses through the building envelope. The healthy-home assessment adds health and safety layers: the question isn't just whether the house is efficient, it's whether it's safe to live in.
These goals reinforce each other. Proper ventilation reduces both energy waste and pollutant buildup. Moisture control protects both the building structure and the people inside it. The HHP program addresses indoor pollutant reduction and lower utility costs together because those problems share physical causes — that's the basis on which the program was designed.
What You Can Do — and Where to Start
Some steps are within reach right now:
- Test for radon. EGLE's Indoor Radon Program offers low-cost kits. Call 800-RADON-GAS or visit michigan.gov/egle to order one.
- Install CO detectors on every level of your home, including the basement. Replace them according to the manufacturer's schedule.
- Don't disturb suspected lead paint without certified guidance. If you're planning renovation work in a pre-1978 home, get a lead paint assessment first.
- Control moisture. Fix leaks, improve bathroom and kitchen ventilation, and address any standing water in the basement or crawlspace. Reducing moisture is one of the most direct ways to reduce mold growth and pest activity.
If you live in Highland Park or East Detroit, WWGT's programs may cover a professional assessment at no cost. Contact us to find out where enrollment stands and whether your address is currently in the service area.
For the energy-cost side of older-home performance — insulation, air sealing, weatherization — see our article on why Detroit energy bills are so high — and what free programs exist to lower them and the companion piece on why Detroit's older homes cost so much to heat. For the broader context of who bears these burdens and why, see our piece on energy justice in Detroit.
Learn about WWGT's Healthy Home Production program
Contact us to check program eligibility
Frequently Asked Questions
How do I test for radon in my Detroit home?
Order a low-cost test kit through EGLE's Indoor Radon Program at michigan.gov/egle or call 800-RADON-GAS. Kits are typically placed in the lowest livable area of the home for 48 hours (short-term) or up to 90 days (long-term). If results come back at or above 4 pCi/L, EPA recommends mitigation. A healthy-home assessment also includes a review of radon risk pathways — foundation conditions, pipe penetrations, and other entry points — as part of its scope.
Is lead paint in my walls dangerous if it's not peeling?
Intact, undisturbed lead paint on a stable surface poses lower immediate risk. The hazard increases when paint deteriorates — chalking, peeling, or blistering — or when renovation work generates dust. If you have a pre-1978 home and are planning any repair or remodeling work, get a certified lead inspection before you start. WWGT's Healthy Home Production program addresses lead paint condition as part of its whole-home assessment.
Why is asthma so much higher in Detroit than the rest of Michigan?
The MDHHS data points to a combination of factors. Indoor triggers in older housing — mold, pest allergens, combustion particles, poor ventilation — play a significant role. Outdoor air quality in a historically industrial city adds to the burden. The two don't operate separately: a child who comes home from outdoor air pollution to a home with mold and cockroach allergens faces a compounded load. Addressing the indoor environment is one part of the response that families and programs can directly act on.
What does WWGT's Healthy Home Production program include?
HHP covers indoor pollutant reduction and utility cost reduction together. A healthy-home assessment looks at radon risk pathways, combustion safety, moisture and ventilation, lead paint condition, pest entry points, and indoor air flow. The program works on the physical conditions inside the home that drive health hazards and energy waste. Visit our Healthy Home Production program page to learn more.
Do I have to pay for a healthy-home assessment?
It depends on program eligibility. For homeowners in Highland Park and East Detroit, WWGT's programs may cover a professional assessment at no cost. Contact us to check where enrollment stands and whether your address falls within the current service area.
We Want Green Too is a Detroit-based 501(c)(3) nonprofit, EIN 45-5324148, founded in 2007 by Gloria J. Lowe. We work on energy-efficient, healthy housing and green-economy careers for Detroit residents and veterans. Visit us at wewantgreentoo.com.
