Friday, June 29, 2007

Choosing sustainable materials

What exactly is a sustainable building material, and how can you be sure you’re choosing the best one?

A Life Cycle Analysis (LCA) can be used for balancing the environmental and economic performance of building products. LCAs calculate the total embodied energy of a product by considering harvesting, manufacturing, distribution and eventual disposal. There are many LCA resources available, a few of which are included here.

  • Perhaps the most well-known LCA system, the Athena Sustainable Materials Institute is attempting to make their software more accessible to builders. They offer free demo software for their Environmental Impact Estimator available on their website.
  • The BEES (Building for Environmental and Economic Sustainability) software, created by National Institute for Standards and Technology (NIST) Building and Fire Research Laboratory can be downloaded for free from here. It is aimed at designers, builders, and product manufacturers and includes actual environmental and economic performance data of many products.
  • The Boustead Model version 5.0, by Boustead Consulting out of the UK, offers a free demonstration disk from here. The program hosts an extensive database of fuels and energy use, raw materials requirements, solid, liquid and gaseous emissions.
  • ECO-it, created by PRĂ© Consultants from the Netherlands, calculates the environmental load of a product and shows which parts of the product contribute most. A demo version can be downloaded from the website or the full software can be purchased for $147.
  • If LCA software is not available, The U.S. Pollution Control Agency has an Environmentally Preferable Purchasing Guide that explains the “green” attributes of certain materials.
  • If you still have questions about sustainable materials, Dovetail Partners offers detailed reports and information about responsible consumption and sustainable materials.

As an added note, when I choose materials, I prefer to use local materials over anything else. Even if FSC-certified wood is available from China, I prefer to use non-FSC wood from Minnesota. How you choose materials is really up to you.

One thing to keep in mind: a recent study estimated that the wood from a log home could build 12 regular stick-frame homes. However, if this log home was built using logs from the local region, the total embodied energy of that home would be less than from those 12 typical stick-frame houses. The log home construction also increases the demand for large diameter wood, which means people will keep growing it in the forests, and stimulates the local economy. I am not advocating either type of construction over the other, but more the understanding that we need both types of housing in order to stimulate diverse forests, and balance housing needs with embodied energy.

Friday, June 22, 2007

Art with a Consumption Conscience

Ever wonder if that one plastic bag you throw away really makes a difference? Sometimes the numbers we hear don't really mean much. But what if you could see them?

Artist Chris Jordan reflects on human consumption with his new exhibit, Running the Numbers: an American Self Portrait.

You really must see these images to believe them. Make sure you scroll down to the plastic bags!

Tuesday, June 19, 2007

NAHB Green Building Guidelines

I have been facing the real possibility that because a LEED®-trained data collector is not in the Greenbush area, LEED certification may not happen. The rater from the cities is still available, but the travel expenses may be too high to justify the certification. I have been looking into other green building programs for the Greenbush area.

One alternative I've been researching is NAHB's green building program.

The National Association of Home Builder's (NAHB) launched its own green building guidelines in 2005. The voluntary Model Green Home Building Guidelines were designed to be used as a template by home builder associations wishing to start their own regional green building program, or as a green guide for the mainstream home builder. According to studies conducted by NAHB, more than half of their members (who build more than 80 percent of homes in the US), will be incorporating green practices into new homes by the end of 2007.

NAHB's green building program encompasses sustainable design elements through the following categories:

  • Lot Preparation and Design
  • Resource Efficiency
  • Energy Efficiency
  • Water Efficiency/Conservation
  • Occupancy Comfort and Indoor Environmental Quality
  • Operation, Maintenance and Education
NAHB's program is not third-party certified, but like LEED it is voluntary and based on a point system. Some builders have stated that NAHB's approach to green building standards has been much more comprehensive and easier to use than LEED. The most important difference to note is that NAHB addresses the embodied energy of building materials through Life Cycle Analysis (LCA), while LEED does not. Also, LEED has demonstrated preference for remaining in the top percentage of "high-performance" buildings, while NAHB's program is targeted to hit the average builder. NAHB has plans to release a national green building program, complete with certification, in early 2008.

Because I'd like the Greenbush program to receive some sort of certification and NAHB does not currently offer certification, I am reviewing Green Globes and other green building programs as well. I am not giving up on LEED yet either, and hopefully a solution will soon arrive. I will keep you posted.

Friday, June 15, 2007

Basics of a Green Home, and the Integrated Design Approach

This is from the National Association of Home Builder's page. I love this image because it still looks like a typical house. Building green doesn't have to be scary. It doesn't mean tentacle tubes poking from walls or living in darkness to save energy. It simply means building a better building.

There are many ways to build green, and it doesn't necessarily entail a full-blown overhaul of your thinking. Start out small, by choosing a few things you'd like to improve, and add things to your next project. It's better to do something than to do nothing.

Just remember that for maximum benefit, starting in the design stage will save costs in the long run. A fully integrated whole-system design approach leads to an efficient, high-quality product and happier customers. Everyone has a learning curve with green, so don't forget the value of these new experiences. Embrace the opportunity to learn from the subcontractors that you will interact with when using a whole system design approach, and enjoy teaching them new things as well.

For more information on the integrated design approach, consult the Whole Building Design Guide.

Tuesday, June 5, 2007

Finding a Local Energy Rater

Now that LEED® registration is almost complete, it is time to choose an Energy Rater.

The Greenbush project is taking the Energy Star path of the LEED Energy and Atmosphere category. This means the home design will be evaluated for meeting Energy Star requirments, and then will be tweaked to increase the level of energy efficiency beyond Energy Star standards. More points can be achieved by incresing the level of energy efficiency. An energy rater is needed to measure and verify this data. They will sign off on the LEED Energy and Atmosphere credits and send the information to our LEED provider.

Typically the LEED provider can suggest an energy rater to you, and it will most likely be someone that they have had positive experience with (and someone that can do the non-energy data collection too - more about that later). If you are building a LEED Home in a rural area like I am, I would suggest shopping around a little bit. The rates to certify a home as Energy Star differ from rater to rater. You can use anyone as long as they are RESNET (Residential Energy Services Network) certified (this is true whether you certify the LEED Home using Energy Star's Guidelines, or LEED's guidelines for Energy). With energy-efficiency increasing in popularity, the number of RESNET certified raters is growing daily. To find a certified RESNET rater close to you, go here.

It is my strong belief that if you can go local, you should. Buying local has less environmental impact and stimulates the local economy. Using a local energy rater also means that value is placed on their services, which promotes sustainability for the entire community by increasing the likelihood that more people will seek energy-efficient practices after word-of-mouth advertising.

By choosing a local rater, there are economic benefits to your project as well. Energy raters in rural communities are typically cheaper than raters found near an urban hub. For example, one energy rater local to the Greenbush project was half as expensive as one based out of the metro area. Most raters charge for transportation and lodging costs as well, which can really add up if you they need to drive 6.5 hours like they would for Greenbush.

The energy rater will perform two site visits to test the home’s energy-efficiency. One is after insulation, just before drywall is installed. The other is just prior to occupancy. The onsite inspections should include the following:

  • a blower door test to test the leakiness of the house,
  • a duct test to test the leakiness of the duct system, and
  • a thermal bypass inspection, which is a visual inspection of common construction areas where heat and cold can escape from a home.*

*information provided by the EPA

Energy rating is just one part of the LEED criteria verification. Other portions of it need to be verified as well. Sometimes, this person will be the same person who is your Energy Rater, if they have the proper training. As the LEED-H program has not been offiically rolled out yet, there may not be someone local to Greenbush to perform the non-energy data collection, and a rater from the metro area may have to be used. I am currently checking with the LEED provider on the options. I will get back to you on that progress as soon as I know!

Monday, June 4, 2007

Understanding Energy Star and LEED®

The Energy and Atmosphere category of LEED® for Homes can be met through two different paths. One path consists of meeting LEED's own specific energy criteria. The other path is to follow Energy Star standards, increasing the level of energy efficiency beyond Energy Star standards to obtain more points.

Energy Star is a joint program of the U.S. Environmental Protection Agency and the U.S. Department of Energy. It was formed in 1992 on a voluntary-basis, and has become a noted standard for energy-efficiency. There are currently more than 750,000 Energy Star rated homes in the US -- 200,000 of which were built in the last year. That number is expected to exceed 2 million by the end of the decade.

New homes built to Energy Star standards are at least 15 percent more energy efficient than homes built to the 2004 International Residential Code (IRC). Your local codes may be more or less stringent depending on where you live. Energy Star homes utilize effective insulation, high performance windows, tight construction practices and ductwork, Energy Star lighting and appliances, and energy-efficient heating/cooling equipment.
Besides having lower energy costs, energy-efficient homes pollute less (16 percent of U.S. greenhouse gas emissions are generated from the energy used in houses nationwide).

Homes earn Energy Star certification through
verification of a third-party organization or an individual called an energy rater. There are two verification options. One is called the Performance Path, in which the energy rater uses software to model the home’s energy use, verifying that it meets a target HERS score. This option looks at existing homes or design plans that have already been completed. The other option is the Prescriptive Path. This home is built using a prescribed set of construction specs that meet the program’s requirements.

Concern about energy-efficiency is increasing (obviously), and the Energy Star name is becoming more familiar to the general public.
A study from late 2006 shows that 68% of consumers recognize the Energy Star label and that energy-efficiency is important in the buying process. Some mortgage companies now offer incentives to buyers purchasing energy-efficient homes (such as Energy Star), and there are tax benefits for building an Energy Star home as well.

The Greenbush project will follow the Energy Star route so that the house will be certified as both LEED and Energy Star. I am very excited because it is a great way to provide both Energy Star and LEED education to contractors in the Greenbush area. Rural communities are especially interested in energy efficiency, they just don't always have all of the information!

Click here to find an Energy Star energy rater, builder, or lender in your area. When we get further along in the process, I'll explain more about Energy Star.

Friday, June 1, 2007

Podcasts offered by Energy Star

I like to think that by using an electronic calendar, I'm minimizing my paper use. But according to the EPA, most of us do not realize that even when not being used, these products can consume substantial amounts of energy.

Energy Star is offering podcasts on how the many small gadgets and electronic appliances affect our energy conumption. They are also in written format.

Click here to learn how your little gadgets may be sucking energy.