Confusion & Complexity – Can Green Building Programs Be Simplified?
If you’ve 
ever had to dive into the details of the green building and energy efficiency programs for homes, you’ve experienced the operational definition of the word ‘complexity,’ along with a bit of ‘confusion,’ too, I’m sure. I know I have. Unfortunately, the programs all just keep going further and further down that path.
If you’ve ever had to dive into the details of the green building and energy efficiency programs for homes, you’ve experienced the operational definition of the word ‘complexity,’ along with a bit of ‘confusion,’ too, I’m sure. I know I have. Unfortunately, the programs all just keep going further and further down that path.
Take the ENERGY STAR new homes program, for example, the one I’m most familiar with. Version 1 required only one inspection, a home energy rating (for the performance path), and no checklists. Version 3, which becomes mandatory for builders wanting the ENERGY STAR label on their homes starting next January, requires 2 inspections, a home energy rating, and 4 checklists.
I understand the need for it from the perspective of the program administrators. Building and energy codes are catching up with voluntary program requirements, so they have to keep moving forward. Program leaders also have attempted to clarify the ambiguity of early versions of program requirements. And they have to make sure that the program is meaningful and that when the program label appears on a home, that home is significantly better than homes without the label. I get all that.
It just seems like we’ve lost our way, that we’ve all gotten blinded by a confusion of checklists, worksheets, prescriptive measures, and certification levels. Not to mention the confusion that comes from having so many different programs out there. If you’re a builder, you have to decide if you’re going for ENERGY STAR, LEED for Homes, EarthCraft House, NAHB Green Building Standard, Environments for Living… It’s not an easy task.
One of the first points of confusion that participants in the ENERGY STAR program face is whether to certify via the prescriptive or the performance path. That sounds pretty clear-cut, right? When you take a closer look, however, you find that the prescriptive path has performance requirements (e.g., testing for duct leakage and infiltration rates), and the performance path is chock full of prescriptive requirements. Just look at the 4 checklists required in ENERGY STAR Version 3.
As constructed, the performance path is differentiated from the prescriptive path by its requirement for a HERS rating. It’s based on how the home is constructed, how it tests out, and how the software does the energy modeling. It doesn’t depend on how the house actually performs, though, and that could differ significantly from the modeled performance. One reason we do it this way is so that the homes certified will carry the program label while they’re for sale, thus helping the builder to market their homes.
But what if we included the performance of a home over its first year of occupancy? Then we could include the actual energy use and calculate the energy intensity, even separating out baseload from the energy used for heating and cooling. It seems to me that this would be one of the best ways to handle quality assurance, too. If HERS raters, builders, and trade contractors know that their work has to pass not only the initial inspections but also a full year’s worth of performance assessments, don’t you think they’ll pay a bit more attention to getting the details right?
We could simplify the requirements for the initial certification and make sure everyone knows that the initial label means only that the home has gone through a process. Even though the energy modeling may say the home will use only $900 of energy per year, for example, everyone will know that that will be compared to the actual energy consumption for the ‘real’ label.
Anyway, those are my thoughts on this Monday morning. I’m interested to hear what you think.
Top photo by acearchie from flickr.com, used under a Creative Commons license. Lower photo by Ian Sane from flickr.com, used under a Creative Commons license.
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A couple of builders made the
A couple of builders made the same face as the girl in the first picture when I told them about the new Version 3 guidelines.
Whose fault would it be if the home doesn’t perform as well in the first year as the rating predicted? The builder, the rater, or the homeowner? Could be messy if you were buying or selling a property based on a specific label that after a year ended up not even labeled at all.
Allison,
Allison,
I continue to have hope as I see you are preparing the ground for your eventual endorsement of the Passive House standard. Lets just cut to the chase and accept the fact that the Europeans have beat us to it.
Allison,
Allison,
I like the idea of actual performance based, including 1 year.
You could still have the prescriptive path, the current performance path and ‘The Enhanced Verified by Living’ Performance Path.
Somehow we as a Rating Community have to offer builders and home buyers a selection of services and a benefit to have the rater more involved in the process. The current performance path, means the rater is more involved than in the past – that takes time. You idea of a Verifiied by Living Path, would also require more time from the Rater.
I agree that GBPs are getting
I agree that GBPs are getting more complicated by the minute, but comparing Home Performance does not compare apples to apples either. If I have 2 identical homes, one with a single habitant, who most of the time is traveling and hardly ever home, and a second house with a couple and 4 kids, 4 computers, 4 TVs, etc, etc., I think it would be hard to compare energy usage for QA and resale information purpose. There has to be a standard design comparison, where all systems are measured with the same criteria, and I think this is one thing where the HERS score is an equalizer.
I agree with Armando. The
I agree with Armando. The influence of occupant behavior on energy usage is huge — if memory serves, FSEC noted behaveor-based usage variance on the order of 400%. I don’t often hear the question “Why is my utility bill so much lower than my neighbor’s, whose house is identical?”, but I know that guy is out there, because his neighbor is calling me.
Jason: Yes
Jason: Yes, it could be messy if we focus on who’s fault it is if a home’s actual performance doesn’t meet the modeling. I think if we use the carrot rather than the stick, though, this can work. We already have the problem of houses that don’t live up to expectations, so let’s acknowledge what the current certification actually means, supplement it, and then reward those that actually perform well. (Of course, if there’s evidence that the initial certification was obtained fraudulently, then finding the guilty parties will be important.)
Terry: I like the Passive House program. I’m a big fan of beefing up the building envelope so you can reduce the equipment needed for heating and cooling. I don’t think PH, as written, works outside of cold climates, however. One of these days I need to write an article on PH.
John: My idea is to add the actual performance so that we can simplify the initial certification process. Let’s reduce the vast tangle of prescriptive requirements – with their checklists, categories, items, sub-items, and footnotes – and focus on the more important issue of performance. What we call the performance path now isn’t really very performance based. It’s just another kind of prescriptive path. If we can do this, then the rater’s job should become easier and be focused more on education and support.
Armando:
Armando: You’ve hit on an important discussion – the difference between asset labels and operational labels. RESNET addressed this in 2009 (download pdf here), and yes, there are certainly difficulties in reconciling the two. I think it’s important to have both and have them support each other. Also, the HERS Index is a kind of equalizer, but there’s a lot of work going on in the energy modeling community now to tie the asset label and the operational label together to improve both.
Bob: Since heating and cooling is often one of the biggest pieces of a home’s energy consumption, even though it’s a smaller piece of the pie in a high performance home, it’s not hard to disentangle it from the ‘baseload.’ The baseload is the water heating, lights, and appliances and is fairly flat through the year. The heating and cooling part shows up as the two peaks riding on top of the baseload when you graph a year’s worth of energy data. Yes, occupant behavior can be huge, but we can still know a lot about how good the initial work was by the energy bills of the occupants. We can also normalize for number of occupants, weather data, and other factors to minimize the differences and get at the essential performance data that we want.
Okay, I agree with Armando
Okay, I agree with Armando too. I like the “One Way” street sign. With families busier than ever, one design standard will be easier to sell. Make it too complicated, and it won’t even register. For example, I think the general public gets the Energy Star label now.
The design standards appropriate for differing climates reminds me of the recommendations for gardening: right plant, right place. Pick a plant outside of your cold hardiness zone (and, if you are fancy, days of extreme heat), and you will get a poorly performing (or dead) plant.
So, it seems to me that you building science guys need to endorse basic standards for design-for-climate. You could start with a general one for the USA, with “cold hardiness” or “humidity” levels or whatever is critical to better performance in better zones. Then those in particular states could break it down further, (e.g., coastal GA v. mountain GA) if it’s necessary.
I just think that it would be handy for architects and builders to look at a map and say, “Oh, I’m building in Zone 2. I will follow these specs.”
As a former public school teacher in GA, I just don’t want any more schools built on a slab, carpeted, and not conditioned over the summers. Scraping off the mold from rug spots and furniture shouldn’t be part of the elementary teacher’s job description. No child should have to breathe that moldy air…especially when the dampness/mold situation could have been prevented in the building’s design.
Allison, you know I like and
Allison, you know I like and respect you, but I take serious issue with this post. Your headline suggests a discussion about green building programs and instead I see a post on Energy Star and Home Performance. The only people who think Green building is about energy efficiency are the folks in the efficiency industry and the under-educated.
Michael:
Michael: You do have a point, and I see now that, although I meant to keep it broadly applicable to green building and energy efficiency programs, I went further down the energy path than I originally intended. I did say, though, that I was using ENERGY STAR as an example, and there’s plenty of excess complexity in green building programs, too. See, for example, our friend Carl Seville’s post, Green Building Programs Got Some ‘Splainin to Do.
You’re right, though, that I need to do more articles that go beyond my almost maniacal focus on energy. I’ve got one in the works for later this week on the greywater system I installed at the house I built, and I’ve had some others in mind also that will cover the distinction between green building and energy efficiency. Stay tuned. I think you’ll find some good stuff here.
I would be interested to see
I would be interested to see what your commentary and feedback would be for programs like Living Building Challenge (the current pinnacle of green building) and MN GreenStar (the most progressive green program that is also Remodeling focused).
Michael:
Michael: Well, I’ll have to do that. Are the guidelines for those programs posted online?