The most recent blogs at Green Building Advisor

What do you do if you’re a builder and your client (that would be me) hands you a material that no one’s ever heard of, let alone installed in this country, and asks you to insulate his house with it? A lot of smart builders would run the other way. Eli Gould, our partner in the Dummerston, Vermont farmhouse we’re renovating (really re-building), took it on as a challenge.

I was a kid a long, long time ago. Seems like it was another century ... another millennium even. Wait a minute — it was another millennium!

That was back in the day when we used to ride bicycles without helmets, apply mercury to our wounds, move seat belts out of the way (if the car even had them), and put our tongue on steel poles in the middle of winter. Of course, in Texas and Louisiana we just ended up with a bad taste in our mouth from those steel poles and wondered why people made such a big deal about it.

Each month in Portland, Maine, a group of building professionals gathers for an evening of serious Building Science banter. The topic is either focused on a specific aspect of building science or opens up a lively discussion of what a Pretty Good House (PGH) would do in our cold climate of Maine. (For more information on the Building Science Discussion Group in Maine, check out the links in the "Related Articles" box, below.)

Kevin Dickson has come across an article about a high-performance house in Massachusetts that has got him wondering whether big photovoltaic(PV) Generation of electricity directly from sunlight. A photovoltaic cell has no moving parts; electrons are energized by sunlight and result in current flow. systems are overtaking PassivhausA residential building construction standard requiring very low levels of air leakage, very high levels of insulation, and windows with a very low U-factor. Developed in the early 1990s by Bo Adamson and Wolfgang Feist, the standard is now promoted by the Passivhaus Institut in Darmstadt, Germany. To meet the standard, a home must have an infiltration rate no greater than 0.60 AC/H @ 50 pascals, a maximum annual heating energy use of 15 kWh per square meter (4,755 Btu per square foot), a maximum annual cooling energy use of 15 kWh per square meter (1.39 kWh per square foot), and maximum source energy use for all purposes of 120 kWh per square meter (11.1 kWh per square foot). The standard recommends, but does not require, a maximum design heating load of 10 W per square meter and windows with a maximum U-factor of 0.14. The Passivhaus standard was developed for buildings in central and northern Europe; efforts are underway to clarify the best techniques to achieve the standard for buildings in hot climates. to become the next big trend in high-efficiency building.

The house is the work of R. Carter Scott and a design team that included Betsy Pettit and Joe Lstiburek of Building Science Corp., among a number of other experts. It was one of eight in Devens, Mass., that Scott’s company, Transformations Inc., was chosen to build for MassDevelopment, the state’s finance and development authority.

In the past, I have been critical of the NAHB’s National Green Building Standard (NGBSNational Green Building Standard Based on the NAHB Model Green Home Building Guidelines and passed through ANSI. This standard can be applied to both new homes, remodeling projects, and additions. ), just as I have been of most other green building programs. While I don’t expect to lose my critical eye, I do believe I have mellowed a bit and developed new opinions about the certification process and each program's role in the industry.

Last week, I drove to Boston for Building Energy 13, the annual conference and trade show of the Northeast Sustainable Energy Association (NESEANorth East Sustainable Energy Association. A regional membership organization promoting sustainable energy solutions. NESEA is committed to advancing three core elements: sustainable solutions, proven results and cutting-edge development in the field. States included in this region stretch from Maine to Maryland. www.nesea.org). There were nine full-day workshops, 12 half-day workshops, and 60 hour-and-a-half sessions, with 10 going on at any one time. I can't possibly do justice to the quality of this event, but I can urge you to go next year and to look for more information about this year's conference on the NESEA website in the coming weeks.

Among the innovative — some might say weird — products we’re trying out at our Dummerston, Vermont farmhouse, none is more unusual than the expanded cork insulation we’re currently installing as a layer of exterior rigid insulation. As I mentioned in a blog last summer, cork insulation has a great story behind it.

Labradors? James Brown? What do either of those have to do with the RESNET conference?! Be patient, my friend. All will be revealed shortly. The 2013 conference sponsored by the Residential Energy Services Network (RESNET) in Orlando a few weeks ago was fantastic. It and Building Science Summer Camp are my two favorite events of the year, and this year RESNET was better than ever.

One thing I learned while following the energy usage of buildings I designed was that as a building’s energy needs are reduced, and the fraction of those needs supplied by solar energy increases, the variation in backup energy (purchased energy) increases from year to year.

Let's look at the monitoring data for our house, and compare the winter of 2011-2012 with the winter of 2012-2013. Due to colder weather and changing lifestyles, we used 23% more energy over these months in 2012-2013 than in the previous year.

GBAGreenBuildingAdvisor.com's library of articles and blogs continues to expand. The newest article to be added to the ever-deeper GBA Encyclopedia covers water-resistive barriers (WRBs).