There are lots of horror stories out there about mold, rot, stink, decay, health problems and even death associated with energy efficiency measures and airtight houses. Most of them come from the early days of 'live' experiments where good things were done, with all the right intentions but only half of the concept was in place...house-as-a-system was not the by-word of the late 70s/early 80s homebuilding/renovating world. And in many instances where new horror stories appear, it's pretty obvious to those who are conversant in building science that 'house-as-a-system' is ***still*** not the by-word of the homebuilding/renovating world.
This week, Joe Lstiburek posted a great article looking back at some of his experiences when he was starting out (and I was still in high school, btw). Check it out here. As usual, it's a good read. Nobody beats Joe up much better than Joe -- acknowledging and learning from mistakes is a hallmark of a good engineer. As someone who came into the world of building science after the messiest of the messy horror stories were ancient history in Joe's books, I didn't experience the a-ha! moments that led to the house-as-a-system approach, but I have benefited from that work, and referred to it over and over and poked at it and challenged it and come out on the other side understanding a little more. Respecting a little more. And yes, one of the first things I was taught to do wayyyyy back in Building Technology at BCIT was how to read a psychrometric chart. So I earned my building science wonk stripes early. (Is it wrong to tell you that I kinda groove on knowing how to read it?)
Articles like this one, that come from those who did the work, tore out their hair, thought out the systems, fixed the problems and use the experience as teaching tools are crucial to understanding why building science has to be such a big part of everything we do in the homebuilding/renovation industry today. People's lives are at stake. Which is where the case for building science should end. Making the case for building science in an economic picture seems trivial after that, but we must include the costs associated with poorly understood or mis-applied buiding science. Uninhabitable houses are a liability at so many levels. A house is a major investment for the homeowner, lender and municipality, to start with -- then there's the local economic development associated with constructing, maintaining and renovating, which involves more lending, and selling, which involves a whole bunch more people: realtors, appraisers, home inspectors...
Physics don't change. The good news about that, is some dreadful consequences are very easy to predict, analyse, and overcome because they can be expected, because many of the ways that heat, air and moisture flows interact can be predicted.