The concrete portion of a vented Trombe wall absorbs heat during the day and the natural convection of the warm air in the space between the wall and the glass helps to heat the room. At night, with the vents closed, the wall provides both radiant and convective heat.
The concrete portion of a vented Trombe wall absorbs heat during the day and the natural convection of the warm air in the space between the wall and the glass helps to heat the room. At night, with the vents closed, the wall provides both radiant and convective heat.

At the base of the Sangre De Christo Mountains in Taos, N.M., sits a small group of what appear to be traditional adobe homes. In reality, these are the Sueños del Cañon luxury condominiums, a cutting-edge model of sustainable development in Southwestern disguise.

Living Designs Group (LDG) and Dreamcatcher Real Estate & Construction teamed up to create Sueños del Cañon as an affordable, ecological community. LDG is a consulting and design firm that incorporates sustainable concepts into its work. For this project, concrete masonry was a key part of LDG's energy-conscious plan.

Because of their high thermal mass, concrete and masonry stay warm or cool longer than other materials, reducing the strain on heating and cooling systems by moderating temperature changes inside a building. This feature makes concrete and masonry prime materials for projects geared toward energy conservation.

At Sueños del Cañon, special concrete block Trombe walls are being added to the wood frame construction to allow for passive solar gain. Trombe walls (most often pronounced “trome”) are named after French inventor Felix Trombe, who popularized the concept in the 1960s.

A Trombe wall is typically a south-facing wall of concrete or CMUs with an external pane of single or double pane glass. A ¾- to 2-inch-wide space is left between the glass and the concrete. The sun shines through the glass and heats the wall, which is coated with dark paint or stucco to better absorb heat. In 8 to 10 hours heat passes through an 8-inch-thick Trombe wall, so as the sun goes down, the radiant heat from the wall heats the room. By morning, the wall has cooled and the process begins again.

Trombe walls are most effective in sun-filled climates such as New Mexico or Arizona. A design modification that allows the home to take advantage of natural convection is to add vents at the top and bottom of the wall. As the air between the glass and concrete is heated, it rises and circulates into the room through the top vent. This action allows for a more direct gain of warm air throughout the day. Adjustable vent covers can be closed at night to prevent the backflow of warm air out of the room.

Although the concept of Trombe walls is not new, it is being revived by innovative designers focused on sustainable building. “Green” amenities distinguish Sueños del Cañon from other condominiums with comparable price tags. Trombe walls are offered as a $3500 upgrade. “Solar features like Trombe walls can be stereotyped as a 1970s solar thing,” said Doug Patterson, director of Systems Design and Architecture at LDG. “You just have to look at it differently. The product can be a value-added green feature that doesn't need to be expensive, and fits within a contemporary design.”