The most recent blogs at Green Building Advisor

Designing an HVAC System for a Cold Climate

Posted on January 19, 2015 by Scott Gibson in Q&A Spotlight

Randy Bunney is building a new house in a challenging environment — north central Minnesota, where overnight temperatures plunge well below zero and heating-degree days over the last three years have averaged more than 8,600 annually.

The high-performance, passive-solar home will be a relatively small 1,100-square feet with two bedrooms, an open living-kitchen-dining area, 1 1/2 baths, a mudroom and a mechanical room. Bunney is planning on exterior walls insulated to R-40, the roof to R-60, and "near airtight" construction.

What is Comfort?

Posted on January 16, 2015 by Martin Holladay, GBA Advisor in Musings of an Energy Nerd

Buildings have had central heating for only about 140 years, and they have had air conditioning for only about 80 years. For most of human history, people took comfort in winter from a stone fireplace — somewhere to heat up a kettle or warm one’s hands.

Once heating and cooling systems were developed, almost everyone wanted them. Why? Because people want to be comfortable.

Three Types of Heating and Cooling Loads

Posted on January 14, 2015 by Allison A. Bailes III, PhD, GBA Advisor in Building Science

What is it about the number three? You've got the Three Musketeers, the Three Little Pigs, and the Three Stooges. Then there's three strikes (what every pitcher wants), three branches of government (executive, legislative, and judicial), and the three kinds of people (those who can do math and those who can't). And let's not forget three on a match, three wise men, and threepeats.

Today we'll look at another big three: the three types of heating and cooling loads. Do you know what they are already?

An Off-Grid Solar Community

Posted on January 12, 2015 by Ajahn Sona in Guest Blogs

Birken Forest Monastery is a retreat center in the mountains of British Columbia. It's located at an elevation of 4,000 feet at Latitude 51, and experiences about 9,000 heating degree days (Fahrenheit) per year. The buildings are about 15 years old.

We are off the grid. The nearest electricity line is 4 miles away, and it would cost about $200,000 to bring grid power in. (Then, of course, we would still have to pay for the electricity.) So off-grid it is, and will remain.

Building a Foam-Free House

Posted on January 9, 2015 by Martin Holladay, GBA Advisor in Musings of an Energy Nerd

Many green builders want to build a foam-free house — that is, a house without any rigid foam insulation or spray foam insulation.

How Replacing a Furnace Can Make You Less Comfortable

Posted on January 7, 2015 by Allison A. Bailes III, PhD, GBA Advisor in Building Science

Let's say your trusty old furnace is at the end of its life. You've got to buy a new one, so you call your HVAC(Heating, ventilation, and air conditioning). Collectively, the mechanical systems that heat, ventilate, and cool a building. company and they rush over to make sure you don't freeze during the next cold snap. They go and take a look at your furnace and find its capacity. They come back and tell you that you have a furnace rated for 60,000 BTUBritish thermal unit, the amount of heat required to raise one pound of water (about a pint) one degree Fahrenheit in temperature—about the heat content of one wooden kitchen match. One Btu is equivalent to 0.293 watt-hours or 1,055 joules. per hour and then talk to you about some of the options.

Interior Paint and a Back Porch for the Potwine Passivhaus

Posted on January 6, 2015 by Alexi Arango in Guest Blogs

As they set out to build a single-family 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. on Potwine Lane in Amherst, Massachusetts, Alexi Arango and LeeAnn Kim asked themselves, “Is it possible to live without burning fossil fuels?” One measure of success would be meeting their goal of net-zero energyProducing as much energy on an annual basis as one consumes on site, usually with renewable energy sources such as photovoltaics or small-scale wind turbines. performance. This is the twelfth blog in a series.

Choosing a New Wood Stove

Posted on January 5, 2015 by Scott Gibson in Q&A Spotlight

Patricia Appelbaum is in the market for a new wood-burning stove, one without a catalytic element, to provide mostly supplemental heat for her 1,600-square-foot home. There are a lot of models to choose from, and that's part of the problem.

Redefining Passivhaus

Posted on January 2, 2015 by Martin Holladay, GBA Advisor in Musings of an Energy Nerd

In January 2012, Katrin Klingenberg, the founder of the Passive HouseA 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. Institute U.S. (PHIUS), announced that her organization would develop a new passive house standard for North America — a standard that differed from the Passivhaus standard developed in Darmstadt, Germany.

The Potwine Passivhaus Gets Insulation and Drywall

Posted on December 30, 2014 by Alexi Arango in Guest Blogs

As they set out to build a single-family 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. on Potwine Lane in Amherst, Massachusetts, Alexi Arango and LeeAnn Kim asked themselves, “Is it possible to live without burning fossil fuels?” One measure of success would be meeting their goal of net-zero energyProducing as much energy on an annual basis as one consumes on site, usually with renewable energy sources such as photovoltaics or small-scale wind turbines. performance. This is the eleventh blog in a series.

Register for a free account and join the conversation


Get a free account and join the conversation!
Become a GBA PRO!