The Green Tech Fallacy

[bcwessel]

Why the most environmentally friendly building is the one we've already built
Emily Badger | Atlantic Cities | 24 January 2012 | LINK (http://www.theatlanticcities.com/housing/2012/01/why-most-environmental-building-building-weve-already-built/1016/)


Reusing an old building pretty much always has less of an impact on the environment than tearing it down, trashing the debris, clearing the site, crafting new materials and putting up a replacement from scratch. This makes some basic sense, even without looking at the numbers.

But what if the new building is super energy-efficient? How do the two alternatives compare over a lifetime, across generations of use?

“We often come up against this argument that, ‘Oh well, the existing building could never compete with the new building in terms of energy efficiency,’” says Patrice Frey, the director of sustainability for the National Trust for Historic Preservation (http://www.preservationnation.org/). “We wanted to model that.”
Preservation Green Lab (http://www.preservationnation.org/issues/sustainability/green-lab/), the Trust's sustainability think tank, has published a new study today (http://www.preservationnation.org/issues/sustainability/green-lab/)examining this that puts big numbers behind the finding that the greenest buildings aren’t in fact state-of-the-art ones; they’re the ones we already have.

Retrofit an existing building to make it 30 percent more efficient, the study found, and it will essentially always remain a better bet for the environment than a new building built tomorrow with the same efficiencies. Take that new, more efficient building, though, and compare its life cycle to an average existing structure with no retrofitting, and it could still take up to 80 years for the new one to make up for the environmental impact of its initial construction. . .

The most interesting data lies in how new buildings compare to existing ones if we don’t even bother to retrofit them. This chart from the report shows how much time it would take for a new building that's 30 percent more efficient to overcome – through all that efficiency – the impact of its construction (much of which lies in the use of all that new material).

http://cdn.theatlanticcities.com/img/upload/2012/01/20/chart__.jpg

This means that you could put up a new mixed-use building in Portland that's 30 percent more efficient than an otherwise identical one across the street that already exists. It would still take 80 years for that new building to have – over its entire life cycle – the better environmental impact. That conclusion contradicts the common perception that we may innovate our way out of climate change with ever more efficient new stuff.

[BigCityBoy]

Why the most environmentally friendly building is the one we've already built
Emily Badger | Atlantic Cities | 24 January 2012 | LINK (http://www.theatlanticcities.com/housing/2012/01/why-most-environmental-building-building-weve-already-built/1016/)


Reusing an old building pretty much always has less of an impact on the environment than tearing it down, trashing the debris, clearing the site, crafting new materials and putting up a replacement from scratch. This makes some basic sense, even without looking at the numbers.

But what if the new building is super energy-efficient? How do the two alternatives compare over a lifetime, across generations of use?

“We often come up against this argument that, ‘Oh well, the existing building could never compete with the new building in terms of energy efficiency,’” says Patrice Frey, the director of sustainability for the National Trust for Historic Preservation (http://www.preservationnation.org/). “We wanted to model that.”
Preservation Green Lab (http://www.preservationnation.org/issues/sustainability/green-lab/), the Trust's sustainability think tank, has published a new study today (http://www.preservationnation.org/issues/sustainability/green-lab/)examining this that puts big numbers behind the finding that the greenest buildings aren’t in fact state-of-the-art ones; they’re the ones we already have.

Retrofit an existing building to make it 30 percent more efficient, the study found, and it will essentially always remain a better bet for the environment than a new building built tomorrow with the same efficiencies. Take that new, more efficient building, though, and compare its life cycle to an average existing structure with no retrofitting, and it could still take up to 80 years for the new one to make up for the environmental impact of its initial construction. . .

The most interesting data lies in how new buildings compare to existing ones if we don’t even bother to retrofit them. This chart from the report shows how much time it would take for a new building that's 30 percent more efficient to overcome – through all that efficiency – the impact of its construction (much of which lies in the use of all that new material).

http://cdn.theatlanticcities.com/img/upload/2012/01/20/chart__.jpg

This means that you could put up a new mixed-use building in Portland that's 30 percent more efficient than an otherwise identical one across the street that already exists. It would still take 80 years for that new building to have – over its entire life cycle – the better environmental impact. That conclusion contradicts the common perception that we may innovate our way out of climate change with ever more efficient new stuff.

Having not read the article i am going to say hogwash. First over, not every new building is 'green'. Secondly, this may be a good argument for the advent of asbestos back in the day. Further, is it only 30% more efficient from, say, buildings built in the late 19th century? I doubt it. And yet i'm willing to bet most buildings around the world are from that age or at leat at least 40 years old.

i guess the real trade-off is if the new buildings perform better than the older ones for similar costs (inflation-adjusted, of course). I'm willing to bet they do. until we can get away from the CO2 and heat souorce being generated from oil it may not be possible.

If you have ever lived in a Century brick house with no insulation and triple brick walls you would know that the heating bills are much higher than in a modern 2 storey home of similar size. 30% my ass.

[bcwessel]

Maybe you should read the article, and the study from which its argument is derived before dismissing the claims outright.

You've missed the real point, which is that we generally fail to account for the embodied energy (and capital, for that matter) of most things in the built environment when we attempt to derive environmental and efficiency calculations on the built environment. And that all of this embodied energy comprises a much greater share of these equations than we might generally assume, once the calculus has been done.

[BigCityBoy]

Sure, i can appreciate that. Maybe i will read the article. So what the study is eesentially saying is that a brick is a brick and once made and placed. it takes so many BTU's etc to demolish it and build some other envelope. I get it. I'm just not sure i believe it just yet - after all, oil is still fairly cheap at 80 - 90 dollars per barrel and some renovations are much more expensive when trying to retain some of the original structure. Costs in labour and materials are oten more expensive and only carried out to preserve the 'heritage' of the building.

Don't get me wrong, I'm all for preserving existing old structures but your not going to get me crying over a 1950's tower block that has been knocked down to make condos or something else more modern.

Also, does the study consider the increased labour, energy and technology involved in restoring an old structure to a modern standard or is it simply the efficiency once up and running?

[BigCityBoy]

Is this model biased having een completed by the Preservation Society of who knows where. Show me some real studies.

"Building reuse typically offers greater environmental savings than demolition and new construction. It can take between 10 to 80 years for a new energy efficient building to overcome, through efficient operations, the climate change impacts created by its construction. The study finds that the majority of building types in different climates will take between 20-30 years to compensate for the initial carbon impacts from construction.

Sure, it will take 20-30 years. But as you may well know, buildings last for much longer than that.

[BigCityBoy]

I'm not saying that you or the site don't have some merit. Simply playing the Devil's advocate.

As per: The Bottom Line: Reusing existing buildings is good for the economy, the community and the environment. At a time when our country’s foreclosure and unemployment rates remain high, communities would be wise to reinvest in their existing building stock. Historic rehabilitation has a thirty-two year track record of creating 2 million jobs and generating $90 billion in private investment. Studies show residential rehabilitation creates 50% more jobs than new construction.



I find this statement very difficult to believe.

Quite simply, if this were true, why would the economy suffer so much when there is a lack of new construction in it? C'mon, man! everyone knows that construction is the last to start and first to end in an economic up-turn / downturn. Not some reno guys doing some renos but actual growth!! C'mon, man!

[bcwessel]

Rehabilitation limits the amount of work that can be completed by heavy machinery, as well as the work that can be completed on scale (due to the lack of uniform, assembly line-style tasks present on-site). The more labour-intensive a task is, the more labour hours you will require to complete that task - hence, the greater number of jobs the project will create to produce the same number of new units.

It's also quite likely that, on average, renovation projects pay more per hour of labour completed, this coming as a result of the lack of standardized tasks, and the greater likelihood that higher-skilled artisan trades will be needed to complete some of the work. These same basic mechanism emerge in studies comparing the construction of bikelanes vs. the construction of highways, which demonstrate similar gains in jobs created for the smaller, more labour-intensive projects over those which favour heavily mechanized construction done at scale.

Charles Marohn of BetterCities.net (formerly New Urban Network) produced an excellent 5-part series (http://bettercities.net/news-opinion/blogs/charles-marohn/14876/growth-ponzi-scheme-part-1) explaining why our current models for tracking economic growth and prosperity - reliant as they are on new home construction, as you rightly point out - may be seriously flawed in their conception. I also recommend The Enigma of Capital (as I have in the past) by David Harvey as a useful tool for understanding past and current spatial fixes in the context of economic growth, as well a tool for predicting what future spatial fixes may lie ahead. (Richard Florida's latest book, The Great Reset, deals with this topic at some length as well.)