The most recent blogs at Green Building Advisor

The Uniform Mechanical Code Looks to Limit Flex Duct

Posted on December 21, 2016 by Allison A. Bailes III, PhD in Building Science

Some people love flex duct. Some people hate it. Some of us are OK with it if it's done right.

As I've documented here numerous times, many flex duct installations leave a lot to be desired. They sag. They're kinked. They're twisted around pipes.

If there's something bad that can be done with flex duct, someone has done it. And the result of all those mangled flex duct installs is poor air flow, which creates comfort problems, uses more energy, and is one reason systems get oversized.

From Theory to Reality: Building a Net-Zero Home

Posted on December 20, 2016 by Thomas Lambert in Guest Blogs

Can you really build a net-zero-energy house based on information learned from an online course? The short answer is yes, and we have CreekSide Net ZeroProducing 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. Calculating net-zero energy can be difficult, particularly in grid-tied renewable energy systems, because of transmission losses in power lines and other considerations. to prove it.

My wife and I are often asked two questions: Why did we build a net zero energy house? How did we know how to build it?

The "why" is really an evolution of our values — of “walking the talk.” We have always been eco-minded and dreamed of doing something with alternative energy to reduce our carbon footprintAmount of carbon dioxide and other greenhouse gases that a person, community, industry, or other entity contributes to the atmosphere through energy use, transportation, and other means. .

Upgrading a Crawl Space

Posted on December 19, 2016 by Scott Gibson in Q&A Spotlight

David Meyer's Seattle-area home is built over a crawl space, and after stripping out the old insulation and vapor barrier he is ready to re-insulate and seal the area. After looking into his options, Meyer is leaning toward "encapsulation," meaning the crawl space would be sealed (unvented), with the insulation on the walls, not between the floor joists.

A Caribbean Island Transitions to PV

Posted on December 16, 2016 by Martin Holladay in Musings of an Energy Nerd

Most of the electricity generated in the U.S. comes from power plants that burn coal or natural gas. Although an increasing percentage of our electricity comes from 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. (PVPhotovoltaics. Generation of electricity directly from sunlight. A photovoltaic (PV) cell has no moving parts; electrons are energized by sunlight and result in current flow.) arrays and wind turbines, there are two problems with these renewable energy sources. First, electricity generated by PV arrays or wind turbines is still somewhat more expensive than electricity generated by fossil fuel plants (although the cost of solar and wind continue to drop).

CarMic House: Retrofitting the HVAC System

Posted on December 15, 2016 by Carri Beer and Michael Hindle in Guest Blogs

Editor's note: Carri Beer and Michael Hindle are renovating a 1954 house in Catonsville, Maryland. Hindle is a Certified 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. Consultant and owner of Passive to Positive. Beer is a registered architect who has been practicing sustainable architecture for 18 years. She is an associate principal with Brennan+Company Architects. This post details Michael's redesign of the HVAC(Heating, ventilation, and air conditioning). Collectively, the mechanical systems that heat, ventilate, and cool a building. system. For a list of the couple's posts, see the “Related Articles” sidebar below.

Can This Panelized System Solve Your Enclosure Problems?

Posted on December 14, 2016 by Allison A. Bailes III, PhD in Building Science

If you want to build a superinsulated, airtight house, you run into some difficulties. How do you deal with the extra thickness of your walls and ceilings when you add all that extra insulation? What's the best way to ensure you hit your airtightness goal? And how do you do all that while keeping the process manageable and the cost affordable?

The new Build SMART panelized system has some answers.

To Improve Wind and Solar Power, Bring Them Together

Posted on December 13, 2016 by Anonymous in Guest Blogs


What’s keeping solar and wind power from fully taking over the electric grid? For starters, the sun only shines during the day. Wind blows intermittently, is seasonally variable, and is not always blowing when the energy is needed. But what if solar and wind work together?

A SIP Roof Repair in Wisconsin

Posted on December 12, 2016 by Allan Poole in Guest Blogs

A year ago, I looked on the web for information about repairing a poorly designed SIP(SIP) Building panel usually made of oriented strand board (OSB) skins surrounding a core of expanded polystyrene (EPS) foam insulation. SIPs can be erected very quickly with a crane to create an energy-efficient, sturdy home. (structural insulated panel) roof system. I found Green Building Advisor and posted questions here. It was suggested that I share my roof repair experience for the benefit of others who may be grappling with the same misfortune as mine. Here is my story.

Green Building in the Trump Era

Posted on December 9, 2016 by Martin Holladay in Musings of an Energy Nerd

Most green building advocates are concerned about global climate change. So what are we to make of the election of Donald Trump?

Well, there is bad news and good news.

The bad news is that Trump is ignorant about basic economic facts relevant to the energy industry and is disdainful of scientific consensus. There’s more bad news:

  • Trump believes that climate change is a hoax;
  • Trump has promised to withdraw from (or, as he puts it, to “cancel”) the Paris Climate Agreement;
  • Trump has ridiculed supporters of renewable energy;
  • Daylight Savings Time Isn’t Worth the Trouble

    Posted on December 8, 2016 by Anonymous in Guest Blogs


    On November 6, public service announcements reminded us to “fall back,” ending daylight saving time (DST) by setting our clocks an hour earlier. On November 7, many of us commuted home in the dark.

    This semiannual ritual shifts our rhythms and temporarily makes us groggy at times when we normally feel alert. Moreover, many Americans are confused about why we spring forward to DST in March and fall back in November, and whether it is worth the trouble.

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