44 Ways #20: Use Thermal Mass to Maintain Even Temperatures

Hello! This is Episode 420. This is Way #20 of the 44 Ways to Create Your Sustainable Home series, and we’re continuing through Section Five: The Building Envelope, A Sustainable Skin.

In the last episode, Way #19, we covered airtightness and ventilation. We talked about what it means to build tight, why homes don’t need to breathe, and what ‘ventilating right’ looks like in practice.

In this episode, we’re looking at one of the most commonly discussed, and commonly misunderstood, elements of the building envelope: thermal mass.

Way #20 is: Use Thermal Mass to Maintain Even Temperatures.

[For all resources mentioned in this podcast and a free, downloadable PDF transcript, head to www.undercoverarchitect.com/420]

You’ll hear architects, builders and sustainability consultants talk about thermal mass as a worthwhile inclusion in any home. This can include concrete slabs, brick walls, rammed earth, and other ‘heavy’ forms of construction.

Even water-filled features are used as thermal mass in homes.

Thermal mass is a powerful tool when the conditions support it, and it’s designed with the right approach for the climate and site. However, when those conditions aren’t in place, it can make your home harder to heat, harder to cool, and less comfortable overall.

In this episode, I take you through what thermal mass actually is and how it works, the three conditions that need to be in place for it to function well, when thermal mass will work against you, why the ground your slab sits on and the finish that covers it matter just as much, and what to ask your team.

As always, if you'd like to access a full transcript of this episode and links to any resources I mention, head to www.undercoverarchitect.com/420.

Now, let's dive in!

RESOURCES MENTIONED IN THIS PODCAST: