A Case for Airtight, Ventilated Homes

Why the air quality inside your house may matter more than the air outside

Last year many people were surprised to see the headlines about a study linking living near golf courses to a higher risk of Parkinson’s disease. It didn't relate to diet or lifestyle choices, it was about exposure. Specifically, pesticides drifting through the soil and groundwater - but I’m here to make a case about the air as well. 

While there are aging and genetic risk factors for Parkinson’s disease, a look at this map will help understand that it is also an exposure driven disease. 

Parkinson's prevalence map of the United States. Depending on how studies are conducted and what they look for, outcomes will vary slightly.

As more data comes out, something has become obvious to me - your home and built environment is your primary environmental filter. 

We spend roughly 90% of our time indoors. If long term exposure matters, the building envelope quietly becomes a health intervention. In Michigan, this matters even more. The industrial Midwest has long been recognized as a Parkinson’s prevalence corridor. The important question isn’t just “how clean is our air” but rather “how much of that outdoor air has leaked into your home from years prior and will in the future?”

Parkinson’s has multiple entry points

Modern research shows that Parkinson’s disease doesn’t start the same way in everyone. Instead, several pathways can converge:

Pathway	What triggers it
Genetic	Inherited mutations
Gut	Microbiome disruption and inflammation
Post-viral	Immune activation after infection
Chemical	Pesticides & solvents
Airborne	PM2.5 and ultrafine particles

While PM 10 is of concern, filtering PM 2.5 mitigates PM 10 by default.

What is PM 2.5?

In simple terms, PM (particulate matter) 2.5 (the fine particles you inhale ~ 2.5 micrometers or smaller) 

What air pollution actually does inside the brain

In laboratory research scientists exposed animals to tiny particles similar to air pollution. The particles triggered the defining biological features of Parkinson's by protein clumping, oxidative stress, mitochondrial failure, and dopamine neuron death. 

That protein is the signature lesion of the disease. These environmental particles don’t just irritate the tissue, they initiate real pathology. 

Other reviews now show that pollutants can reach the brain through both the lungs and the gut-brain axis and are strongly linked to neurodegeneration. And similar mechanisms also appear in Lewy body dementia. 

Then the human evidence followed. People with long term air pollution exposure show higher Parkinson’s risk and different disease characteristics.  And neurologists are now openly acknowledging environmental exposure as a meaningful contributor to neurological disease risk. 

Put together:

-PM 2.5 and fine particulates can damage neurons

-Exposed populations get the disease more often

-Clinicians accept the connection

Here's where I come in and why building standards need to be changed

Most homes have been and still are being designed to unintentionally inhale outdoor air through cracks. 

-Attic Leaks

-Rim joists

-Crawlspaces

-Wall cavities

-Ductwork gaps

We already acknowledge the high leak areas around windows, doors, and fireplaces. Often noted as infiltration ventilation, it sounds harmless, and kind of makes sense in some ways, but it’s causing susceptibility to moisture damage, high energy bills, and exposure to traffic particles, industrial dust, pesticide drift, and wildfire smanotheroke. 

Think, every hour….for decades….you don’t notice it, because the air looks clear, but PM 2.5 is invisible. Something 30 times smaller than a human hair. 

Climate change is making indoor air worse

In Michigan, wildfire smoke now travels across entire countries and we are susceptible to the PM 2.5 coming from the western United States, as well as Canada. And it’s not just fires. In fact, at the beginning of the meteorological summer in the US, a giant plume of Saharan dust travels from Africa to the United States causing air quality drops and visible haze in the sky. The outdoor air is becoming more variable and more extreme and most homes were build and designed in the 1970 era. 

Climate change is increasing particulate matter in several ways: 

• More wildfires

These have not been small increases, often 10-30 times the normal levels

• Warmer winters

Snow melting and drying becomes airborne road dust

• Longer dry seasons

More suspended dust in rural and suburban air

• Urban heat  

Heat accelerates chemical reactions that create fine particulates

The modern way of homebuilding needs to address air tight building envelopes that benefit your health through controlled ventilation. Air enters one location, filters continuously through known airflow. 

If the average human takes about 20,000 breaths a day. Over 30 years, that’s over 200 million exposures. 

The question is no longer whether we can afford to build airtight, but whether we can afford not to. The future of health, energy efficient housing is sealed, safe, and sustainable.