This Paint May Alter How Builders Fight Mold And Moisture Damage

Lilypad, a new-to-market paint and primer system that is engineered to act as a dehumidifier by pulling moisture out of the air, promises to protect homes from damage caused by excess moisture. 

The paint captures moisture when humidity rises and returns it as humidity falls, and play a role in regulating room air temperature. The innovative concept, which has the financial backing of D.R. Horton and PulteGroup, could save homebuilders money, as excess moisture complaints, callbacks and litigation costs builders and developers billions of dollars annually. 

Whether or not Lilypad can break through as a scaled, sustainable business in the nearly $36 billion North American paints and coatings market, time will tell. Competing with the sector’s giants, PPG Industries (US), The Sherwin-Williams Company (US], Axalta Coating Systems (US], RPM International (US) and BASF SE (Germany), will be no mean feat, given the ongoing research and development commitments and investments these industry leaders pour into innovation.

At least for the moment, Lilypad appears to be out in front with a technological moat.

In an interview with The Builder’s Daily, Dr. Derek Stein, founder and CEO of Lilypad’s Sommerville, Mass.-based parent company Adept Materials, said that one gallon of Lilypad paint can absorb more than a soda can’s worth of water. 

“This is the one and only paint that’s on the market that’s designed to actually absorb moisture. If you take Lilypad paint and apply it to the wall, the film will actually absorb excess humidity as it starts filling the room, and then, when it dries, it resets itself by slowly letting it back into the space. So it’s regulating humidity, Dr. Stein said. 

The primer aids the paint by controlling vapor flow, ensuring that moisture exits into a ventilated space rather than collecting in the walls. It will release any trapped moisture, essentially working as a one-way valve for water vapor. Even as the paint absorbs moisture, the wall remains dry to the touch. 

The costs associated with excess moisture

The excess moisture problem is particularly pronounced in bathrooms, which rapidly fill up with moisture when the shower is left on for extended periods of time. According to Stein, Lilypad paint has enough capacity to capture the moisture produced from hot showers, which keeps the humidity levels below the mold threshold. 

Without this dehumidifying capacity, mold can accumulate and cause long-term health problems for residents. Almost half of homes nationwide have experienced a persistent dampness and mold problem, conditions that strongly correlate with a rise in respiratory illness and asthma. 

For developers and builders, these health issues also present a financial liability, as complaints, callbacks and litigation tied to moisture-related insurance claims can prove costly. 

D.R. Horton and PulteGroup decided to invest in Adept Materials, joined by Massachusetts Clean Energy Center (MassCEC), a state-run economic development agency, and Point Cove LLC, an investment firm. In 2024, the homebuilders led a $4 million seed round, which provided the funding for Lilypad. 

“They appreciate how important moisture problems are. It is a top-five ticket item in callbacks and litigation,” Stein said. 

Bathrooms aren’t the only rooms of concern. Mold issues are also common in kitchens and laundry rooms. 

“[Homebuilders] spend a lot of time and money addressing issues that are hard to pinpoint. So resilience has real value,” Stein added. 

For context, today’s energy-efficient homes, which are built “tighter” to restrict air movement, can be more conducive to mold growth if moisture becomes trapped during construction. Moisture intrusion and resulting mold are leading causes of construction defect lawsuits, with builders often held liable for issues arising from faulty flashing, poor site grading, or plumbing failures. Builders may pay between $1,000 to $3,000 more per home for better vapor barriers to prevent future, more costly remediation.

Adept Materials also worked with scientists from the National Laboratory of the Rockies to test the temperature-regulating effects of Lilypad. The researchers found that Lilypad can reduce energy consumption by 5%, or even more if further improvements are made. 

“The way that the water is working in the paint is kind of like a phase change material. When it’s released, when it’s time to evaporate, it provides a cooling effect, the same way that our sweat cools our bodies. And when it gets cold and clammy, and it gets absorbed, it releases heat, so it has this temperature-regulating effect as well,” Stein said. 

Use cases for this technology

Lilypad is the first commercial product to utilize Vaporwisp, a moisture-regulating technology created by Adept Materials. It is first going direct to consumer, but PulteGroup and D.R. Horton have expressed interest in piloting the technology, and Adept Materials hopes to roll out the product to the homebuilding sector in the future once the company scales. 

Adept Materials also partnered with the Boston Housing Authority, which plans to deploy Lilypad paint into about 30 to 50 public housing units in the city. Once they apply Lilypad, the housing authority will conduct controlled tests on units with and without the paint to assess the effectiveness of the product. 

“The developments where we’ll be piloting this, they don’t have exhaust fans in the bathrooms. If you have something that can soak up as much water in 20 minutes as the exhaust fan does, it’s much, much cheaper to put on a lick of paint than to go in and do ducting work,” Stein explained. 

A problem that can’t be ignored

The idea for Lilypad was born out of a lab at Brown University, where Stein was a physics professor for more than 15 years. 

The product started as a student project for the Solar Decathlon, where the team built a solar-powered home and uncovered a problem. They found that airtight, energy-efficient houses trapped too much moisture, a problem that didn’t receive much attention. This realization led to the research that created Lilypad. 

“People are working on air tightness and energy efficiency. People are building homes that are more and more like beer coolers, and are able to hold stuff in. That’s great for thermal efficiency, because you’re not letting heat in or out. But at the same time, those same buildings tend to trap in moisture,” Stein said. “While everyone was focused on the heat, there was very little being focused on dealing with those moisture issues.”