Learning from the Past: Thermal Mass Walls

It is often said that learning from the past helps us avoid future mistakes. Could it be possible that techniques and constructions methods for homes 100 years ago could help shape and guide our green building ideas of today? To answer this question, let’s look at vernacular (or native) construction methods that were used in Texas.  A type of building commonly used by Hispanic settlers in the 1800’s was a jacal. This skeleton of this structure was small upright intermediate posts between large upright corner posts. These posts were built around and filled in with rubble, rammed earth, stone, or sticks, before being mudded or plastered both inside and out. The resulting walls were thick and solid, about 6 to 10 inches wide. This thickness helped to insulate the building, keeping the inside cool during hot summer days. This same idea of a thick exterior wall was also used in adobe construction.

This idea of a thick exterior wall (what we call a thermal mass wall) helping to regulate heat transfer is something we’re very interested in at Stearns Design Build. We are intrigued by dynamic thermal mass walls that prevent heat from entering interior spaces in the summer and exiting interior spaces in the winter. We at Stearns are currently dreaming up and developing a two chamber wall system that will, like a thermal mass wall, help to heat and cool interior spaces. This positively answers the question that began this blog—techniques from the past can help us develop innovative building ideas.

Check out our blog about rethinking wall systems for more information about other wall types and how they relate to ideas about efficiency.