Autoclaved Aerated Concrete (AAC) is a masonry product with a long history in much of the industrialized world, yet it has seen relatively limited use in the United States. The two presenters, Dan Levy and Steve Bluestone, both find AAC preferable to wood as a building material for many reasons, including resistance to fire, water, mold pests, and structural loads. And AAC does all of the above with a single material installed by a single trade.

The phrase “natural building” tends to evoke images of humble, rustic homes built out of mud and sticks by barefoot idealists in rural backwaters. The natural building movement has come of age, however, and today's professionally-executed natural buildings can match any green building in air-tightness, energy use intensity, durability, and aesthetics, all while achieving reduced levels of embodied carbon and enhanced social benefits.

Super-insulated construction, simple yet efficient building systems, and modern solar generation have made net zero energy a realistic project goal for new construction even in cold climates. However, achieving this without the use of red-list materials is a serious balancing act. Moisture control, air tightness, and thermal isolation are critical; evolving envelope products must be tested.

Existing buildings have a unique story to tell, and we as designers and engineers must tune our design process to "hear" how our buildings actually perform. On-site monitoring of dynamic environmental conditions provides empirical evidence for building performance, which adds granularity to energy modeling practices and empowers the design team to effectively analyze unique envelope characteristics.

Our speakers are building enclosure consultants steeped in wall moisture solutions through data-rich research, computer simulations, lab testing, live performance monitoring – as well as a myriad of “house-calls” to clients. They’ll offer takeaways on building moisture-safe walls, including insulating sheathing, ventilated claddings, inward vapor drives, and vapor retarder paints.

The biggest hurdle for energy efficiency in the built environment today is how to improve the energy efficiency of our existing housing stock in an affordable manner. These three practitioners bring several years of experience to the fore. They have seen what works, what doesn't, and why. The session will review the best building practices of how to view, evaluate and perform an energy upgrade to a property. Average square foot costs on energy efficiency return will be discussed and what can be the expected energy reductions from certain projects. This session will focus on some of the easier energy-efficiency upgrades to be taken now and what to put off to employ our next generation. Evaluation of the existing available financial resources to be used for offsetting the owner costs and how they might be improved. Lastly, they will address when a project is beyond the scope of affordability and what telltale signs to look for.

Airtightness testing has long—since the 1980’s—been used to test high-performance housing. The 2012 version of the International Residential Code requires testing of every new home. Recently there has been a growing trend of testing the airtightness of large buildings as well. This session reviews why one would invest in airtightness testing for a large building, how the testing is done, how the results are interpreted, and how this information can be used.