The “Lock-In” Concept and Passive House Construction
Alan and I just returned from the 18th annual International Passive House Conference in Aachen, Germany. This incredible three-day conference featured some of the superstars in the Passive House community as well as influential European policy makers, including Dr. Wolfgang Feist, founder of the Passivhaus Institut. We effectively witnessed a watershed moment in the adoption of the Passive House standard in European policy, and solid evidence of wide-scale, successful implementation of all types of Passive House projects across the globe. And I am happy to report that North America was well-represented. Our GO Logic presentation was one of several demonstrating Passive House market viability in North America. Of the many inspiring, interesting, and in some cases very geeky perspectives that we were exposed to, there is one that has really stuck in my mind that needs to be better understood in order for anyone—be they policy makers, lenders, or homeowners—to make sound decisions regarding investment in reduced building energy consumption. Dr. Diana Ürge-Vorsatz, director of the Center for Climate Change and Sustainable Energy Policies at Central European University, presented this new perspective using the catchphrase “lock in.” When you look at the long-term impact of different levels of energy-efficiency in buildings across a 50-year span, taking an incremental approach to renovations—achieving, say, a 40% improvement in building performance—is actually a very poor strategy, Dr. Ürge-Vorsatz explained, as compared to waiting several years until a proper Passive House–level building shell can be implemented. How could that be? Well, across a 50-year period, on a macro scale, a moderate, LEED Gold–level energy retrofit will hold the greenhouse gas emissions from building energy use to only a 46% increase from today’s levels. This is not such a bad result. Consider what would happen if we do nothing to improve energy efficiency by the time the global population is 9 billion people. Building energy use will increase by 110%, with CO2 emissions increasing by 68%. Draw your own conclusions about what will happen next. Meanwhile, a Passive House–level renovation approach will actually reduce energy use of buildings from today by 34%. That means the difference between doing a Passive House renovation over standard, incremental improvements is actually an 80% difference in CO2 levels over 50 years!
Graph courtesy of the Global Buildings Performance Network
