Posts Tagged ‘insulation’

the greenest building is the one already built

September 2, 2009

Guess who is finally saying what I and others in preservation have been saying for a while – LEED certification is not a great measure of environmental impact? Actually, it is coming from the horse’s mouth – the certifiers themselves, who found – shockingly – that many of the new green designs did not PERFORM as they were designed. From the New York Times a few days ago:

“But in its own study last year of 121 new buildings certified through 2006, the Green Building Council found that more than half — 53 percent — did not qualify for the Energy Star label and 15 percent scored below 30 in that program, meaning they used more energy per square foot than at least 70 percent of comparable buildings in the existing national stock.”

One of the disadvantages of the LEED system compared to the other systems is that it is a voluntary program that – until now – had no certification process. If your architect or engineer said your system would use 50% less electricity, then you wrote that down and got credit for it. You got credit and you advertised it as a LEED certified building whether or not you ever remembered to turn out the lights. Or look at the electric bill.

There are other systems out there. Canada uses Green Globes, which is more focused on energy use, and both Green Globes and LEED are based on the earlier British BREEAM system. Dunno why, but like television, we get all our good ideas from the Brits. At any rate, LEED focused initially on materials and production, not operations. Which is of course where all the action – pollution and waste – is.

But there is a problem in the focus on use, too. I have often written about the irrationality of the replacement window. I first addressed this issue back in 2001 and have presented on it in numerous venues (Chicago, Joliet, Plainfield, Elgin, to name a few). My conclusion for the last eight years has been the same: window replacement is driven by marketing, not energy efficiency.

It is ironic that the “green” and “sustainable” concern of the last decade has been used primarily to sell tons and tons of mostly plastic products. Energy efficiency in individual products and buildings has improved dramatically, but buildings also got bigger and one is tempted to believe we got a whole lot of Jevon’s paradox – increased fuel efficiency at the micro level leads to increased use at the macro level. Like highways – more lanes means more use and congestion, not less. Jevon figured this out over a century and a half ago.

Plus the hegemony of green marketing has created a massive disconnect between data and interpretation. I was struck by the March issue of National Geographic, which featured a thermographic image of “an older house in Connecticut.” The roof and eaves were red and orange, indicating heat loss. The window panes were blue, indicating little heat loss, and the caption announced the installation of new double-paned windows. The walls were green, indicating some thermal loss, and they were yellow-orange just outside of the window panes – on the window frames.
nat geo mar09s
How was this data interpreted? The caption indicates that the new windows were blue and noted that heating could account for half the energy costs for a house. This is wrong on a whole bunch of levels. First, the thermographic image with the glowing red roof shows the obvious: HEAT RISES. It doesn’t travel sideways. 80% of it goes up, regardless of your windows. There is no way window replacement can save more than 20% of heating costs. What the image showed was that the owners of the house didn’t insulate the attic properly.

Second, the image actually illustrates the biggest fault of window replacement: poor installation. The window frames were glowing yellow and even RED in one portion. This meant that the new tight replacement windows were not preventing thermal loss but pushing it away from the pane and into the frame. Exactly what I said in 2001 and every year since – unless you address the window frame, a super tight window may simply push the thermal loss AROUND the window pane and through the frame. Did they caulk???

What would have been useful would have been a thermographic image of the same house BEFORE they changed the windows. Then we could understand the impact – and skill – of the installation. Why didn’t they address the big issue, the roof?? I’m not surprised that a big time mag like NG goofed this up, because the marketing of replacement windows has inoculated us against a lot of common sense facts we learned about thermodynamics back in grade school. But come on – how can you draw conclusions without a baseline?

The government noted that the peformance of its pre-1930 buildings exceeded the energy efficiency of their buildings built 1930-2000. And those older buildings can be made even more efficient with a little insulation and caulk.

I am glad that LEED is improving – it is coming up with a better list of criteria to account for the embodied energy of existing buildings and fabric. It is now starting to look at performance rather than design. But we all have a ways to go.

HISTORICAL NOTE: I am now in the 4th year of this blog. 248 posts. Read them all here.

Getting the LEED out

February 28, 2009

Reusing an existing building saves 35 tons of CO2 production –

“We can’t consume our way to sustainability” – Carl Elefante, AIA

“Confronting energy reduction with technology in lieu of conservation is short-sighted-
-the problem is conservation is not very sexy and difficult to package and sell. ”
Neal Vogel, Restoric LLC

Neal is a longtime friend and colleague and one of several experts who have seen the limitations of LEED (Leadership in Energy and Environmental Design), which was introduced this century by the U.S. Green Building Council and has made new buildings more energy efficient. The problem is that LEED at the beginning virtually ignored old buildings, despite the fact that an old building’s carbon footprint is always less than a new one. Much of the “Green Building” industry was driven by marketing efforts to push new products.
Of course this makes sense, because you can get sponsors for LEED if it is focused on flogging new products. What the marketing needs to do is distract your attention from the fact that each green product must be manufactured, packaged, stored and transported by fossil fuels. But the market for those products was enough to drive not simply an industry but a professional training and rating system that certifies both professionals and buildings. LEED has become shorthand for Green in a nation where Green has gone all trendy.
Historic buildings are full of components that don’t require energy for manufacture and distribution but initially LEED gave a mere 3 points out of 69 for inherent conservation. The number for a green neighborhood starts even lower.

Thanks to the efforts of professionals like Barbara Campagna of the National Trust for Historic Preservation and Mike Jackson of the Illinois Historic Preservation Agency, they are coming around to the obvious: it takes less energy to leave something where it is. The greenest building is the one already built. Soon, we hope, LEED will reflect that fact, despite marketing efforts to hide it.
There is a lot of concern nowadays about insulating older buildings as part of the economic stimulus. As I noted a few posts ago, once you insulate your ceilings, you have achieved 4/5 of all the energy savings you are going to achieve. Because heat rises. That is simple and straightforward, but a good marketing effort can still confuse the issue.

A lot of people are looking at insulating walls. Again, there is nothing wrong with the impulse, and in some situations it makes sense. But mostly -like window replacement – it confuses the issue and gets people to focus on 20 percent of the problem. Let me quote Neal at length here:

“You will need to be careful with studying wall assemblies–construction has evolved to compensate for our on-tap energy addiction. I think a good starting point would be load-bearing masonry construction versus veneer construction today. Look at assemblies that are considered too expensive to build today, or only for the very, very affluent. If you look at energy as a stand alone criteria, a historic frame house does not stand a chance against a modern wall assembly in pure R-value. You have to consider the broader perspective, like the fact that plaster can retain 70% of its volume in moisture without being destroyed while drywall can only handle 5%. Issues related to indoor air quality, the growing epidemic of asthma, energy required for packaging, transporting, storing new materials, energy required for demolition and processing debris, etc. As it stands, I try to downplay LEED every chance I get because their narrow view of energy and what’s beneficial for the future essentially requires impractical alterations and replacement of historic materials.

I don’t know of anyone who has gathered enough data of residential building types for comparison. My thought on this at one time was to approach the Historic Bungalow Initiative of Chicago–a building type that I think would perform very favorably with relative minor and practical retrofits–to produce energy data on enough houses to be statistically defendable. I think they compared energy improvements to a few houses over a year but I would like to see them expand the study into a much larger group and then compare the data with a typical modest house built today for the same money and in the same climate. Seems like the Trust could get a lot of good PR in our heavy heating dominant climate with this kind of partnership.”
Rock on, brother. I had an 1872 frame house for a dozen years that performed remarkably well in winter and summer because it had real plaster walls. My current house has real brick walls which kick the crud out of the fanciest fiberglass at Home Depot. But Neal’s point is important: If you only measure one variable, a product manufactured with that one variable in mind (and ignoring all the variables of its manufacture and distribution) will outperform the older technology. But looking at one variable is liking buying a new green product that has to be shipped 13,000 miles: you are ignoring other important variables.

You don’t learn to run fast simply by buying a great running shoe.

You need to look at the entire system by doing an energy audit. You don’t answer the question of how green your building is by adding up all the green stuff you bought and stuck in it. You determine how your building is functioning and how you can continually make it more sustainable.
If the USGBC existed from 1880 to 1930 and watched the construction of Victorian and Progressive Era America they would have been passing out medals with a crop duster to keep up with the brick cavity walls, plaster, dutch biscuits and storm windows. Commercial buildings built before 1920 used 80,127 BTUs per square foot. That number climbed steadily to over 100,000 in the 1980s. Only after 2000 did it come down to the level it was at in 1920.

Neal is right – that quality of construction is cost prohibitive today. But you have to remember that the carbon emissions that came with that construction were released into the atmosphere before the Model T.
Without time travel, a new building can’t compete with that.

NEXT DAY UPDATE: Hey I just got my heating bill – I was on the budget plan based on previous owner – $442 a month. Now? $158. Did I replace my windows? No. I closed them. And I insulated the attic. 110 year old windows with triple tracks. Real brick house with real plaster walls. Historic buildings ROCK!