This article was originally featured on our sister site BUILDER.
A big honkin' worry among home builders as they look ahead to 2020, when they hit their deadline to meet net zero energy rules in California--and likely beyond--is not a lack of choice among materials and products to make homes' building envelopes and systems produce as much energy as they use.
It's the installation of said materials and products that's causing building firms a lot of anxiety. What's more, although the prospect of complying with elevated new energy performance standards may intensify the worry, it's already a chronic headache, getting trade crews to work with materials that will only function as they're supposed if they're installed as specified. Every time.
"In every new community in every division in every region we have, we go through extensive training with our supervisors and trades on the right way to install, say window flashing," a senior-level executive for one of the top 10 national home building organizations tells me. "And damned if I don't walk out into the sites some time later, and see it being done wrong. It doesn't take any longer to do it the right way; it's just somewhere along the line, they don't do it."
The stakes are going to rise now, fast and high. The net zero energy challenge centers on air, moisture, and heat, and it's improvements in what homes do with these three elements that are essential to strides in energy performance. Fact is, to deal with air, moisture, and heat in ways that are transformative--i.e. NZE--it takes an ecosystem of professionals to get things right, architects, land planners (lot orientation), engineers, builders and their trade crews, manufacturers and materials suppliers, and the owners themselves.
A study from the Continental Automated Buildings Association, conducted by the New Buildings Institute, entitled “Zero Net Energy Building Controls: Characteristics, Energy Impacts and Lessons,” raises this point:
[The study] found that most ZNE projects “have some controls problems.” The reasons were not based on any specific product, but rather on the process to “get it right” and installation issues. While some firms suggested simplifying processes and avoiding points of failure, the majority said system integration, extensive metering, automation, granular levels of data and feedback are “here to stay” and are “beneficial to the process.”
Materials for a high-performance envelope are a critical area of focus here. From thermal-performing glazing and natural ventilation, to air and moisture barriers, to cladding systems, to insulation, to roofing-related materials, installation is a pain point.
Penetrations, adherents, seams, fasteners, etc.--and where they are--matter. They're the difference--after the air and moisture barriers are set--between an acceptable perm rating or not. Problems or performance. Nail guides for vacuum insulated panels are all good, but getting the installers to abide by those guides is a whole other story.
Point is, manufacturers, materials suppliers and builders have more and more collaborative skin in the game when it comes to training labor crews to install materials the right way the first time. Innovative and attainable new materials and projects will each either be a "cornerstone or a weak link," depending on the installation quality and precision.
What are builders doing to engage manufacturers and materials suppliers in on-site training and supervision of installation crews to ensure their new NZE homes don't fail to measure up and keep performing?