The most recent blogs at Green Building Advisor

Four Ventilation Quotes That Will Take Your Breath Away

Posted on June 24, 2015 by Allison A. Bailes III, PhD, GBA Advisor in Building Science

Looking back over my last several articles, I see that I’ve been going off the deep end. Psychrometrics, hygrothermalA term used to characterize the temperature (thermal) and moisture (hygro) conditions particularly with respect to climate, both indoors and out. analysis of double-stud walls, the physics of water in porous materials... That’s some heavy stuff. So this week I’m going light with some fun quotes about ventilation and indoor air quality.

Site Work Begins for a Pretty Good House in Maine

Posted on June 23, 2015 by stephen sheehy in Guest Blogs

This is Part 2 of a blog series describing the construction of Stephen Sheehy’s house in Maine. The first installment was titled Pretty Good, Not So Big Maine House.

Is This Insulation Too Good To Be True?

Posted on June 22, 2015 by Scott Gibson in Q&A Spotlight

Jan Verschuren has a nicely roofed older house, and a problem to go with it. Cedar shingles have been installed over skip sheathingMaterial, usually plywood or oriented strand board (OSB), but sometimes wooden boards, installed on the exterior of wall studs, rafters, or roof trusses; siding or roofing installed on the sheathing—sometimes over strapping to create a rainscreen. , making for a roof that's not only historically correct but one that allows air to circulate freely beneath the roof deck. Verschuren's next objective is to insulate between the 2x4 rafters, and here's where he has run into a snag.

How To Buy a Ductless Minisplit

Posted on June 19, 2015 by Martin Holladay, GBA Advisor in Musings of an Energy Nerd

Green builders usually specify high-performance windows and above-code levels of insulation, while striving to reduce air leaks in their homes. As a result of these efforts, most green homes have relatively low heating and cooling loads.

Goldman Sachs Is Our Best Bet Against Climate Change

Posted on June 18, 2015 by Bryan Birsic in Guest Blogs

Although it may not be the obvious hero, Goldman Sachs — usually more Vampire Squid than White Knight — and its cohorts could be responsible for transitioning the renewables sector from a fragmented and esoteric industry to one of mainstream dominance. Goldman Sachs has facilitated the development of world-encompassing industries before and they will do it again.

Fundamentals of Psychrometrics, Part 3

Posted on June 17, 2015 by Allison A. Bailes III, PhD, GBA Advisor in Building Science

In Part 1 and Part 2 of this series of articles, we’ve taken a look at what exactly psychrometrics is and defined the top nine psychrometric quantities. Now we’re going to delve into how we can combine those quantities and create the psychrometric chart.

As you might expect, taking nine variables and putting them into one chart puts a lot of information at your fingertips. It also can take a while to figure it all out. On top of all that, having nine different variables means you’ve got a lot of options for how to show them in a chart.

The Case for Nuclear Power — Despite the Risks

Posted on June 16, 2015 by Gary Was in Green Building Blog

Nuclear power is likely the least well understood energy source in the United States. Just 99 nuclear power plants spread over 30 states provide one-fifth of America’s electricity. These plants have provided reliable, affordable, and clean energy for decades. They also carry risk — to the public, to the environment, and to the financial solvency of utilities.

Pretty Good, Not So Big Maine House

Posted on June 15, 2015 by stephen sheehy in Guest Blogs

After adding a big addition to our already too big house in 2006 (what were we thinking?), we have decided to downsize and build a new, much smaller, highly efficient single-floor house for the two of us.

We live on 43 acres in rural Maine, in a town called Alna about an hour northeast of Portland. We love the land and love our house as well. But at almost 4,000 square feet for the two of us, keeping our house cleaned and maintained and heated and so on has become a bigger burden that we need at this point in our lives.

All About Vapor Diffusion

Posted on June 12, 2015 by Martin Holladay, GBA Advisor in Musings of an Energy Nerd

Building scientists talk about several different moisture transport mechanisms. Most of these mechanisms — for example, water entry due to a roof leak — are easy to understand. Other transport mechanisms, like vapor diffusionMovement of water vapor through a material; water vapor can diffuse through even solid materials if the permeability is high enough. , aren't quite as intuitive.

First, some basic definitions. Water vapor is water in a gaseous state — that is, water that has evaporated. It is invisible.

Water vapor diffusion is the movement of water vapor through vapor-permeable materials. Vapor diffusion happens through a solid material even when the material has no holes.

The Difficulty of Stopping Air Leakage Between the House and Garage

Posted on June 10, 2015 by Allison A. Bailes III, PhD, GBA Advisor in Building Science

A home with an attached garage is usually a home in which people breathe more carbon monoxide (CO). Of course, having an open carport or detached garage is better for air quality (and a feature that usually gets points for you in green building programs like LEED for HomesLeadership in Energy and Environmental Design. LEED for Homes is the residential green building program from the United States Green Building Council (USGBC). While this program is primarily designed for and applicable to new home projects, major gut rehabs can qualify. and EarthCraft House), but what if you don't want to give up that attached garage?

Register for a free account and join the conversation

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