Much of my work these days is certifying homes under LEED, EarthCraft, Energy Star, and the National Green Building Program (NGBP). My day-to-day work includes energy modeling and site inspections, but I find that I spend most of my time explaining and interpreting the different programs to builders, telling them what to do to achieve certification. Each program has minimum requirements, all slightly different. These requirements are not always straightforward or intuitive, and most builders struggle to do them right. The requirements range from straightforward to downright obtuse, and while most of them seem simple to me, on every job I struggle to get the information I need from my clients.
My favorite oddball requirement is the “Framing Waste Order Factor” calculation required for LEED for Homes certification. The builder is required to prepare a document showing that their order does not have more than an average of 10% waste figured into it. Their formula is Waste Factor = (Lumber Ordered-Lumber Needed)/Lumber Needed. No one needs to verify that the actual order is correct, or that there is in fact no more than 10% waste. The intent is good—to not over-order and to minimize waste—but the practice is a rote exercise that most builders do without understanding the point. I find myself challenged to explain the reason behind this requirement; I just let builders know they need to do it.
One of the more logical requirements that is difficult to obtain is an accurate HVAC Manual J Calculation. It seems that few HVAC contractors understand how to prepare an accurate report, often oversizing systems out of habit rather than designing them for the actual house loads. Also, while the reports are supposed to be delivered before the equipment is installed, they rarely are, and mistakes are usually identified well past the time to make any corrections. I recently received a report that included 23 people in a four-bedroom house with window U-factors that were much higher than those actually installed. The house is finished, and I am still waiting for a corrected report.
Is there a better answer out there?
It is certainly a good thing that green building programs are raising the bar, but I am concerned that they may drive away some builders because of their complexity. Making something complicated is a lot harder than making something simple and effective. Fellow Green Policeman Michael Anschel and I have been noodling around with the idea of a more prescriptive green building program. It is little more than an idea, but it would work something like this: Based on your climate, you would choose among a set of pre-determined roof, wall, and floor assemblies, mechanical systems, window and door efficiencies, etc. Any variation from the defined packages would require permission, not unlike the current ID and CIR applications in the LEED for Homes program. A program like this would be much more inclusive and easier to manage than the current programs in the marketplace.
It concerns me that some of the green building programs (and I realize that Energy Star is not actually a green building program, yet), while helping to create high-performance buildings, still have a fairly small impact on our building stock, particularly existing buildings. So what if a tiny fraction of new homes meet LEED, EarthCraft, or NGBP certification? Sometimes I think that I would rather see every building be 10% better than the last one through manageable, incremental changes, than only have a few super high-performing ones.
What’s going to happen next?
One big challenge on the horizon is Energy Star Version 3. Since Energy Star is the base level for most green programs, they are all going to have to raise their own bars significantly very soon. In the current market, some builders are electing to forgo certification of their homes as a cost-reduction strategy. How many more will we lose as the standards (and costs) increase? I am not making the case to lower standards; we do need to continue to raise them. I do believe, however, that we need to make the process simpler in order to keep the industry engaged.
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