In part 1 of this article, we discussed air tightness, dew points, and a preferred insulation technique in Passive House. The next topic that I want to discuss are the best exterior veneer assemblies for custom homes in Atlanta Georgia. I modeled 2 standard Exterior Veneer we use here in Atlanta. They are as follows:
I have just finished my Phase 3 training, in Golden Co. This week. We are officially Passive House US consultants. We plan on being certified next month at the Passive House Conference in Portland, OE.
Today I am going to talk about the effects of Super Air Tight Buildings on wall assemblies / dew points in the Atlanta Climate. A typical wall assembly on a new construction homes in Atlanta, Georgia contains 2 x 4 studs filled with insulation. On the exterior we have OSB sheathing, covered by an air tight / moisture barrier (I use Typar), and a veneer, usually brick or a cementitious cladding. On the interior we have ½ gypsum board painted usually with 2 coats of paint / primer.
There is an unsettling discrepancy between consumers' views on "environmentally-friendly" products and their actual purchasing behavior. Surveys over the past year have revealed potentially useful data regarding this issue. The good news is twofold: regular buyers of green products are buying even more, and almost all consumers are interested in making green purchases. The bad news: despite the interest, only about half of these consumers are actually finding green products, and half of those end up purchasing them. What is the best method to increase these numbers?
My blog this week is about the ECOlution Event on Thursday, October 14th in Atlanta. The Melissa Carter Transplant Fund at Piedmont Hospital and the Georgia Transplant Foundation (GTF) are teaming up to host the second ECOlution event on Thursday, October 14, 2010 at Mason Murer Fine Art in Atlanta.
Last week I posted the first part of my interview with Randy Schwartz, principal and CEO of Buildynamic, Inc. Randy was first involved in renewable energy issues more than 30 years ago, and continues his engagement with isses from the standpoint of residential design / build and new technology development. Today's blog features part two of my interview with Randy.
Of the homes you have built, which are your favorites, why?
Some projects have been more gratifying than others. I have a number of favorites...some would be obvious to those familliar with the body of work, and some less so. Obviously, I am proud of the house on Spyglass Bluff. It was conceived and executed as sculptural art, and we are making it available this year on the GSEA solar tour in October. It was done as a spec house, which has been and remains an interesting experience. I had complete aesthetic control, and was able to do things with that house that, so far as I know, have not been done in or out of Atlanta. It is in harmony with the site in ways that can only be understood by standing in the house. The passive solar and energy conservation aspects are an outgrowth of a certain level of environmental sensitivity. The site spoke. I believe that the house actually has a soul.
Back in the late 80s, I did a number of small spec homes out in Covington, GA that, looking back on it, were precursors of the work that Buildynamic has done. They were probably the only starter (ranch) homes that were being built with 2 x 6s at the time. We did some interesting things with the interiors, including true vault ceilings, floating horizontal mechanical chases and open floor plans. I put a passive solar batch heater on one of the homes, but don't know if it is still there. Where the site permitted, we opened up the southern exposures with glass, exagerrated the overhangs and insulated the walls and ceilings to a higher standard than was required at the time. We never took a deciduous tree if it was not absolutely necessary. There were some interesting homes built.
I'm proud of the house that I currently live in with my wife. I got to indulge some of my more unconventional aesthic impulses in what was a pretty standard footprint geometry, and it has been and remains a very livable and pleasurable space. We used a lot of reclaimed (insulated) glass and surplus tile. It survived a hit from the Dunwoody tornado in April, 1998, so I am comforted in knowing that it was built correctly.
Most of these homes can be viewed on the www.buildynamic.com website. There is a virtual tour of the Spyglass house that can be viewed here.
What are your suggestions to homeowners regarding energy and water efficeincy?
This is kind of a transition question. The overwhelming majority of housing inventory is already built, and not everybody is going to be able to or want to renvoate or build passive solar. My suggestions right now would be similar to the suggestions of others in the industry who promote conservation and energy efficiency. Do the simple, inexpensive stuff first. Look at your house and figure out the common sense approach. Weatherize. Add insulation, if necessary and practical. Keep your filter furnaces changed on a regular basis, and have the preventitive maintenance on your systems done. Look into a programmable thermostat if you don't already have one...don't leave your AC set at 70 degrees in August while you are at work, etc.
Regarding water conservation, if you are replacing fixtures, I don't know that you can even find standard fixtures that do not already include flow restrictors or other integrated conservation measures.
The homeowner can consider technology applications like the tankless water heaters. The product has gained some traction in the market, but the costs will sometimes discourage the casual purchase. For many, engaging with technology is more of a lifestyle decision than an economic one. Everybody seems to have a set of figures on payback...some look reasonable and some look optimistic and / or unrealistic. Hot water comprises about 20% of energy consumption in an average household, so water conservation is not a magic bullet in and of itself. But the cumulative impacts of tankless systems on water and energy consumption could become measurable over time and, if the consumer is so inclined, it is a good technology to start with.
You might be surprised that I do not advocate for the applicaiton of solar thermal or photovoltaics at this time. That is a different discussion. It's not that I wouldn't like to see the proliferation of solar in residential...I would. It would be great if American rooftops looked like Israeli rooftops. But the current price levels make it hard for me to recommend it to homeowners in good faith.
What are the biggest roadblocks to homeowners regarding the installation energy efficiency upgrades, i.e. solar?
There are two that come immediately to mind. Price and inertia.
This blog will be seen and, hopefully read by people who already have a philosophical disposition towards "green' and, as a whole, are going to be more receptive to the lifestyle choices that embrace alternative technologies. But, unfortunately, that is not sufficient. Sad to say that after more than 30 years, solar remains unable to make its economic case without intervention in the form of tax credits and / or rebates, and the underlying psychology is that it remains a hassle. In the consumer's mind, and not without justificaton, there is an undertow that questions the efficacy of the investment. The bottom line is that the consumer is unable to pull out the credit card and make a discretionary purchase for a solar system. And the concept of the "future cost of energy", or the concept of "geopolitical impact" is too vague to motivate the buyer.
The discussion of the cause and effect would make this either a long article or a short book.
In your opinion, what is the future of renewable energy?
There is a paradox. I believe that renewables have a bright future, but in the current overall framework, is still destined to be a marginal technology. Part of the conundrum is that the underlying alternative energy / green ethic is trying to make the transition from a lifestyle decision into a business model matrix, and that is a long and difficult process. Good people have been working at it for more than 30 years now. The model that we currently operate under is necessary and functional up to a point, but I'm not sure that it is adequate to take us where we will need to be. The interests that support status quo have massive concentrations of capital and are both willing and able to defend their market positions and political standing. And those interests still represent a vital portion of the equation, with or without the advent of a predominantly green energy future, so they cannot and should not be dismissed as obstructionist. 5% of the energy mix is a huge number in both dollars and energy provided, but we should not be satisfied.
As a movement, we spend a lot of our time and energy working to institutionalize our subsidies. There should be some leveling of the playing field, but I think that the greatest obstacle to moving renewables out of the "marginal technology" column is the lack of consumer friendly technologies that can make their economic argument without the interventions of government. In some ways, I think that we have it backwards. We work on the political ahead of the economic: my thought is that if you are able to develop the economic constituency, the political will follow. That said, it is also important that the regulatory framework be put in place that encourages the application of renewables and conservation, and that seems to be happening, particularly as regards code and, to a lesser extent, policy.
The pace of change seems glacial. It is frustrating that we are essentially having the same conversation that we had 30 years ago, but in a much more dangerous world environment where Iran is going nuclear, China holds our debt, we import substantially more of our energy, and the dominant energy producing regions are in continuing political turmoil. One can speculate on what the world might look like if the energy policies of 30 years ago had been allowed to come to full fruition, but that would be writing a "counter history".
It is always encouraging to see the growth in the number of people and organizations now engaged in the issue. It is encouraging to see more projects in the field.
The reservoir of innovation will, I believe, eventually produce the technologies for the marketplace that will allow renewables to gain the traction to become mainstream. Then we might be able to emulate the market penertration models of the PC industry and have some real impact. Some of these technologies will come from conventional channels, and some may come from the small entrepreneurs who still lack the resources to make their case, but might in the future. Current structure favors the former, but my bet is on the latter.
To find out more about Randy's work and to see more photos of his homes, go to http://buildynamic.com/
Posted on Jul 14 by Carl Seville, GBA Advisor
Sarah Susanka, in a talk at a recent meeting of the Green Building Council of the Greater Atlanta Homebuilders Association, was her usual, charming self. Sharing ideas from several of her nine best-selling books about right-sized, well-designed homes, she moved deftly from architectural details to new urbanism. One of her more interesting points was the value of following your personal passions. She discussed her transformation from architect to author, and how she discovered that writing was her passion.