Mars Hill House

Inspired by southwestern architectural traditions from Chaco Canyon to La Posada and informed by the site and climate, this home is designed to perform as a net zero-energy building. It is also designed to be a flexible multigenerational dwelling: the first floor is ADA accessible and the building structure is designed to be re-programmed and/or expanded as needed.
The Mars Hill House relies primarily on passive design strategies to reduce its long-term operating energy footprint to achieve its status as a net zero-energy building (nZEB).
Passive solar design applies the understanding of how sun angles change over the course of a year to maximize solar gain during the winter while minimizing it during the summer.
The breezeway at the north end of the courtyard is designed to maximize solar gain. The doors are Nanawalls, a highly insulative wall system that also allows for maximum solar heat gain. Click here to learn more about this product.
Inside this breezeway is a rammed earth wall that acts as thermal mass, in addition to the concrete floor, to store the heat gained during the day. The rammed earth wall was made with soil local to site that was rammed into a form. The striations of different colors of soil make it beautiful as well as functional.
The home has an active hydronic heating system with solar thermal preheat supplying in-floor radiant space heating and domestic hot water.
An Energy Star boiler provides additional heat for space heating and domestic hot water.
The in-floor radiant heating system is divided into zones, allowing different temperatures in different rooms to optimize heating efficiency. This is important with a passive solar home, as some areas receive more heat from the sun than others.
The solar PV system at the entry also acts as a shade structure. This type of solar panel can utilize light from both sides to make electricity.
The wall system is made of grouted concrete masonry units produced locally, with local materials, by Block-Lite. These are followed with an exterior layer of Quad-Lock extruded polystyrene (EPS) blocks with an R-value of 24. Having the insulation layer on the outside prevents heat transfer from the inside and the mass wall modulates temperature differentials from day to night.
The entire exterior of the building is wrapped in Quad-Lock.
The south facing courtyard makes a great outdoor environment year-round, as it receives winter sun that is held by the thermal mass of the pavers and the walls, which also provide a wind break.
Kalwall translucent wall systems are a great way to bring in natural light without the heat loss of a window.
Rainwater harvesting from all roof surfaces supplies a cistern built into the foundation of the attached greenhouse. The cistern is made of block walls sealed with a Xypex coating.
The rainwater is used for irrigating edible plants in the greenhouse.
The home also has a gray water irrigation system for landscape irrigation to further reduce reliance on potable water. Gray water is waste water from lavatories, showers, bathtubs and the washing machine. Kitchen sink and dishwasher effluent are considered black water due to higher organic content.
Low flow fixtures, like this dual flush toilet, throughout the house minimize water usage in the home.
Zero VOC (volatile organic compounds) paints throughout the house contribute to good indoor air quality.
The home is performing even better than net-zero energy! Check out the building’s dashboard by clicking here, to learn more about the project and see the energy and water data from its tracking systems. Note in this image that for each month the net energy use is below zero.