Researchers at Parsons School of Design's Healthy Material Lab have released a study that raises concerns about the "many substances harmful to human health" in a typical prefabricated American home.
Called Manufactured Homes: An Analysis of Health and Environmental Impacts of Common Building Materials, the study highlighted potential negative health effects associated with manufactured homes.
Manufactured homes have been popular among Americans for the last century and peaked in the 1970s, with as many as 500,000 delivered per month. That number is now closer to 100,000 per month, according to data from the US Census Bureau.
"Significant health and environmental risks"
"The extensive use of petrochemical-based materials in contemporary manufactured housing poses significant health and environmental risks," said the Healthy Material Lab Study.
"Plastics and their associated toxic additives are found in nearly every major surface within a manufactured home, including flooring, paint, cabinetry and insulation."
The fossil-fuel plastics mentioned in the research include polyethylene, polyvinyl chloride and polypropylene, with the majority found in kitchens and bathrooms.
Healthy Material Labs executive design director Jonsara Ruth told Dezeen that the presence of potentially toxic plastic material in homes is a problem across the building industry. However, manufactured homes may pose a greater risk due to the drive for affordability.
"It's true, petroleum-based plastic materials are now widespread in new American homes, not just manufactured ones," said Ruth.
"But manufactured housing offers a unique lens: it's where affordability and conventional construction intersect most starkly, often resulting in material choices that externalize health and environmental costs."
Ruth cited the research of Dr Shanna Swan, who has shown the relationship between plastic exposure and the Green Science Policy Institutes Six Classes framework, which outlines harmful chemicals.
"Longstanding reports, dating back to the 1990s, discuss the increased use of petrochemical-based materials in housing and associated health concerns," said Ruth.
"Famously, the FEMA trailer crisis after Hurricane Katrina highlighted the dangers of high formaldehyde exposure in temporary homes."
The move to healthy affordable homes
The study's results are based on information on materials taken from a single home sold by Northstar Systembuilt in Minnesota, as its sample.
Researchers at Healthy Material Lab called the company, posing as buyers to ask questions about the materials.
"We selected one of the most affordable models from one of the largest manufactured home manufacturers in the US," said Ruth.
"While this isn't a statistically representative sample, it's a typical example of conventional, low-cost manufactured homes."
Ruth said she was confident that the material findings were "consistent with what is often found in affordable, conventional residential construction in the US".
Northstar Systembuilt did not respond to Dezeen's request for comment.
According to Healthy Material Lab, the research's goal was to demonstrate that healthier materials could be used in the construction of these homes. Linoleum flooring could replace vinyl, for example, or wood finishes could be chosen instead of plastic ones.
"We're not arguing against manufactured homes," said Ruth, who added there were some examples of manufacturers trying to improve materials, such as a 2000 collaboration between Enterprise Community Partners and Clayton Homes.
"In fact, we're arguing for healthier, low-carbon prefabricated housing at an affordable price point."
The negative effects of plastic on the body have been examined at length in recent years, especially the ubiquity of microplastics. The National Institute for Health showed the potential for microplastics exposure in the indoor environment, though it did not go so far to claim negative health effects from the exposure.
In 2021, Dezeen took a look at the variety of plastics used in the architecture and design industries.
In 2024, Denmark's Natural Material Studio created a home interior completely free of fossil-fuel-derived products.
Photo by Roger Starnes Sr on Unsplash