1. When talking to the general public, people often use “green” and “healthy” as synonyms, but are they the same thing? How would you differentiate between the two?

In many ways, this discussion is like organic foods. People walk into Whole Foods Market and assume because it’s organic food, it’s automatically healthier – which couldn’t be farther from the truth. Granted, organic foods are cleaner than conventional foods, in that they aren’t sprayed with the same pesticides, and are grown in a more sustainable fashion. But organic doesn’t have anything to do with healthier eating. Organic chips, organic sugar, organic soda, etc., all are proof you can still eat food that's organic and bad for you. That’s a good perspective to look at green building through. Green has nothing to do with the health of the building, or it’s occupants. Yes, it’s a wonderful way of thinking about building because sustainable, environmentally friendly, and energy efficient building methods are all valuable and important. But you could build a net-zero, solar-powered, home that is made from sustainably produced materials, and is filled with toxins, built too tightly for building envelope breathability and is the epitome of unhealthy, conventional building.

Healthy building is a value. One that places the health of the people who will live inside of that building first. When you do that one thing, so many other things fall into place. AND, it’s not any harder to make a healthy house green than it is to make an unhealthy one. Green homes and healthy homes shouldn’t be confused with each other – as values, they are pretty distinct. Of course, my feeling is that many green builders gloss over that fact with their clients, and are okay with the assumption that many people make: green building is healthier. This was our experience trying to find a builder that took health seriously – all of the green builders in Austin talked a good game about sustainability and energy efficiency, but few had anything to say about the health of the home and the safety of the materials used.

2. Your model home contains materials and processes that meet both the “healthy” and “green” definition, but was there ever a conflict between the two philosophies, or do they work hand-in-hand with one another?

They can easily work hand in hand. Solar power, water catchment, and other externalities of the building process can be built into any home, healthy or not. The more challenging one involves the building envelope. Conventional systems for making a home energy efficient, inherently wrap the house so tightly that if water ever does get inside it has nowhere to go to escape. Experts I’ve spoken to say water leakage is inevitable in every house. Water trapped inside a house is a recipe for mold, mycotoxins, and a cascade of health problems. So, the desire for more energy efficient houses that started after the oil crises of the 1970’s is what led us to start wrapping our homes in plastic, and sealing them up tight, which made sense at the time, but is a dangerous road to travel, especially when you get a leak somewhere down the line.

It’s not hard to build a breathable building envelope that is extraordinarily energy efficient. Our model home has 10” thick walls with so much thermal mass that the R-value is 38. R-value is a measurement of the energy efficiency. An R-value of 38 is extremely high, and will make for some rock-bottom heating and cooling bills year-round.

3. Some people believe that the original “healthy homes” were built hundreds of years ago in the desert Southwest. Native people used natural materials like adobe for its very effective natural insulating qualities. Do today’s healthy building materials relate in any way to those very early dwellings?

Many of the best building materials out there today are ‘old-school’, like lyme stucco, straw-bale construction, and clay-covered interior walls. Materials from older times were breathable by nature and not design. These materials have withstood the test of time as far as their durability goes. Many modern versions of those building techniques use simple materials in a more complex way, such as ICF (insulated concrete form) walls, which can be very breathable while also being energy efficient. The double-edged sword of relying on so many building technologies is that we haven’t thought through the implications of those materials and techniques – some of which can come back to bite us when they don’t work as planned, especially when our health is concerned.

We named our company ‘Shelter’ because it’s a daily reminder to us that our houses should be thought of as a place that protects you.

4. In terms of current materials available, what percent of a home can be built to “healthy” standards?

Pretty close to all of it. There are some chemicals that are tough to find better versions of, such as the ones that we use to bond water pipes, and some of the caulking and construction adhesives. Luckily, these all cure in short amounts of time, and are typically used in small amounts, thus making their health dangers very limited in duration and location. That being said, the vast majority of a house can be built using safe, healthy materials; materials that have no negative health consequences. I would think of it like this: let’s start building our homes in such a way that you wouldn’t think twice about your kids being around the construction process, and wouldn’t hesitate to have them put their mouths on anything that was finished. If you’re not willing to let your child touch something being used to build your most important environment, what does that say about whether you should use it?

5. You worked with Treehouse in sourcing some materials for your home. Were these materials readily available, or was the process of building a healthy home more of a collaborative effort where everyone learned along the way?

Jason Ballard and his crew at Treehouse are an unbelievable resource for Austin homeowners and builders. The majority of the materials they sell are not available in The Home Depot or Lowe’s, but are no more expensive than the toxic stuff that is. That being said, we used a fair amount of materials that they don’t carry, yet. They are getting more and more into the business of interior and exterior products, and when they are there, you could ideally build a house entirely from things they have vetted. In many ways, I think of them in that role above all others. They carefully and conscientiously research what goes into a product from a health point of view. This is something the conventional building suppliers in Central Texas just don’t do. Which is sad, really. I’ve met people like Brian McCoy, owner of McCoy’s Building Supply, and he is a good, honest man who means well. And there are many others like him. They just haven’t started looking at building materials from a health perspective, even though it’s as important to our health as what we put in our mouths each day. Stores like Treehouse are the vanguard of what I like to think of as a movement towards healthier building.