The most recent blogs at Green Building Advisor

I've written a lot about duct problems (especially those in flex duct) because they're so abundant. A couple of years ago, I even wrote an article in the Energy Vanguard Blog about whether or not flex duct should be banned. My answer was no — but that we need better quality control.

[Editor's note: Roger and Lynn Normand are building a Passivhaus in Maine. This is the 25th article in a series that will follow their project from planning through construction.]

Ralph’s new home will be in Cleveland, Tennessee, not far from Chattanooga and solidly in termite country. And that’s the problem.

In case you haven’t noticed, I’ve been pretty hard on batt insulationInsulation, usually of fiberglass or mineral wool and often faced with paper, typically installed between studs in walls and between joists in ceiling cavities. Correct installation is crucial to performance. in the past. I feel that my complaints and concerns are well justified, but no matter which insulation product is chosen, it has to be installed properly or it just doesn’t work.

Many people mistakenly believe (myself once among them) that spray polyurethane foam (SPF) is the perfect product, is always installed right, and tightens up homes every time.

Bruce Brownell, of Adirondack Alternate Energy, has been creating low-energy, largely passive-solar-heated, resilient homes in the Northeast for forty years — and he’s still going strong. Since 1973, Bruce has built more than 375 homes in 15 states, a third of them in very cold (over 8,500-degree-dayMeasure of how cold or warm a location is over a period of time relative to a base temperature, typically 65°F (although other base temperatures, such as 75°F, can be used for cooling). To calculate the number of heating degree-days (HDD) of a given day, average the maximum and minimum outdoor temperatures and subtract that from 65°F. The annual number of heating degree-days is a measure of the severity of the climate and is used to determine expected fuel use for heating. Cooling degree-days (CDD), which measure air conditioning requirements, are calculated by subtracting the average outdoor temperature from an indoor base temperature.) climates. Most require just a few hundred dollars of heat per year.

I'm new to global warming. I didn't hear about it until 1983. Even thirty years ago, the science behind the greenhouse effect and global warming was well known. French Physicist and mathematician Joseph Fourier is generally credited with being the first to hypothesize that the earth is warmed by its atmosphere and even that we humans can change the climate. That goes all the way back to 1827.

Once upon a time, house insulation meant an extra sweater — and stop your damn complaining. Men were men, women were women, and cats and dogs were cats and dogs, I assume. Houses included features to produce and retain heat, of course — things like double back-plaster walls and central chimneys. But until the 20th century, insulation barely existed in any formal sense.

[Editor's note: Roger and Lynn Normand are building a Passivhaus in Maine. This is the 24th article in a series that will follow their project from planning through construction.]

Twenty years ago, very few residential builders knew what a rainscreenConstruction detail appropriate for all but the driest climates to prevent moisture entry and to extend the life of siding and sheathing materials; most commonly produced by installing thin strapping to hold the siding away from the sheathing by a quarter-inch to three-quarters of an inch. was. These days, however, it’s no longer unusual to see siding being installed on vertical furring strips or a plastic drainage mat. As rainscreens become more common, mainstream builders are beginning to ask, “What’s a rainscreen? How do I know if I need one?”

This article will pull together information to answer the most common questions about rainscreen gaps between siding and 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. .

With any house, there are so many variables that influence the decision to choose one particular mechanical system over another: climate, house size, cost, local availability and cost of fuels and materials, and the lifestyle and preferences of the occupants. There is no “one-size-fits-all” system that we can reliably prescribe for all projects. Phil and I sat down over a good winter cocktail to share our views, anecdotes, battle scars, and wisdom on this important subject.