Two Important Net Zero Homes in Austin
Last Updated: Mar 10, 2025Karen and Dan Cripe live near Austin, Texas, and were living in a typical 2,100 square foot home. After learning about sustainable home design, they came up with a plan to downsize their lifestyle and make energy-efficient upgrades to the house they lived in. However, like many people, their homeowner's association would not allow specific energy-efficient changes that they thought were necessary for a more sustainable and healthy way of life.
Instead of remaining in a large home that was expensive and ecologically costly to cool, heat, and power, the Cripes purchased a plot of land in Round Rock, Texas, about twenty miles from Austin. They began the process of designing and building a 1,400 square foot custom home. Karen was interested in living more sustainably, while her husband was motivated by the potential cost savings accompanying an energy-efficient home.
Once finished, the smaller home achieved net-zero energy status and offered significant monthly savings while allowing this couple to downsize and live a more sustainable and rooted lifestyle.
Table of Contents
- The Cripes Round Rock, Texas Home
- A Blueprint for Achieving Net Zero Energy
- Water Savings in the Heat of Central Texas
- The Red Sky Project
The Cripes Round Rock, Texas Home
The Cripes worked with Solluna Builders to design and build their home. This company specializes in custom house design and has extensive experience with net-zero energy homes. The combination of a plentiful amount of sun in Central Texas, relatively mild winters, and the reduced size requirements for the homemade net-zero energy a guiding goal of the project.
While many homeowners who dream of building a sustainable home might be tempted to move into the countryside and away from the stricter regulatory powers of homeowners associations and local zoning laws, the Cripes home is an example of a sustainable, energy-efficient residential building project that is located in a conventional planned-unit development (PUD).
They did, however, face several regulatory challenges during the building process. Local lenders were not open to financing a non-traditional house, and the owners thus had to reduce their overall loan and pay for much of the construction in cash.
Their home included a geothermal HVAC system and an efficient heat pump for additional heating and cooling. In addition, a rainwater harvesting system reduced their monthly water bills by $70 for an average annual savings of $840.
Other features incorporated into the home that helped maximize energy efficiency included bio-based spray foam insulation, high-quality thermal windows, and a 5kW grid-tied solar electric system. An online monitoring system for their solar panel system allows them to make periodic adjustments to maximize the amount of energy produced. The Carrier Puron Geothermal heat pump offers 722 square feet of living space per ton of cooling and provides free hot water as a byproduct. The home is furnished with the latest energy-efficient appliances, including a magnetic induction cooktop.
Water Savings in the Heat of Central Texas
The average high temperature in Austin, Texas, during August, is a sweltering 97 degrees. For homeowners trying to maintain a green lawn during the long summer months, an enormous amount of water would be needed.
However, the Cripes home maintains a thriving, beautiful lawn landscape even during a horrific drought that saw 100 days with temperatures routinely triple digits. The Cripes home landscape contains no turf grass, which needs excessive water to thrive in hot climates. Instead, the home utilizes an ecological xeriscaping technique that focuses on native plants that radically reduce the watering need. A 500-gallon rainwater collection system is connected to hose bibs that irrigate the garden and lawn.
Tobias Roberts
Tobias runs an agroecology farm and a natural building collective in the mountains of El Salvador. He specializes in earthen construction methods and uses permaculture design methods to integrate structures into the sustainability of the landscape.
