A Cup of Joe: Net Zero Houses and Beyond


The detrimental effects of carbon fuel consumption on the environment have stimulated development of a ‘net-zero’ energy measurement for public and private buildings. A Net-Zero building is defined as one that creates as much energy as it consumes on an annually averaged basis. The primary focus is on creating a building structure that consumes energy efficiently. Once energy efficiency is mastered, the addition of energy production systems will move the project closer to the net-zero goal.

The first consideration for energy efficiency is the building envelope and how that structure controls indoor air quality and moisture levels. Both liquid and gaseous moisture (water and humidity) can cause mold growth and degrade building materials. Preventing entry of either will maintain the air quality and durability of the building over time.

Preventive and remedial measures regarding moisture intrusion include: rainwater-tight detail design, prevention of uncontrolled air movement, reduction of indoor air moisture content, reduction of water vapor diffusion into walls and roofs, selection of building materials with appropriate water vapor transmission characteristics, and proper field workmanship quality control.

In this episode of A Cup of Joe, Dr. Joe Lstiburek is joined by Betsy Pettit to discuss net zero buildings and share lessons learned from past projects.


About Joe Lstiburek, Ph.D., P.Eng., ASHRAE Fellow, Principal, Building Science Corporation:

Joe Lstiburek is the founding principal of Building Science Corporation, one of the most influential, innovative, and respected building science firms in North America. Dr. Lstiburek’s work ranges widely, from providing expert witness testimony to overseeing research and development projects, to writing for the ASHRAE Journal. His commitment to advancing the building industry has had a lasting impact on building codes and practices throughout the world, particularly in the areas of air barriers, vapor barriers, and vented and unvented roof assemblies.

Dr. Lstiburek is also an acclaimed educator who has taught thousands of professionals over the past three decades and written countless papers as well as the best-selling Builder Guides. His commitment to education earned him the hailing “the dean of North American building science” by the Wall Street Journal. You can find additional details on Dr. Lstiburek on our About the Blog page.