Pinless Moisture Meters

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How to use them — and how not to use them

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I got a call the other day from a builder client, who said, “Hey Peter, a new homeowner of mine is super-worried about moisture and mold and is getting scary readings with his pinless moisture meter. Help!”

Pinless moisture meters read from the surface of any material, using an electromagnetic field. Feedback from this field provides information to estimate moisture content. These meters are called “capacitance-based” meters, while pin-type moisture meters are called “resistance-based” meters.

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from Building Science http://www.greenbuildingadvisor.com/blogs/dept/building-science/pinless-moisture-meters

What Exactly Is a Low-Load Home?

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The Air Conditioning Contractors of America (ACCA) has created a task force to provide guidance

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I found out last month that the Air Conditioning Contractors of America (ACCA) is working on a new design manual.  You certainly know of some of their other manuals:  Manual J, Manual S, Manual D, Manual T… maybe even Manual P.

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from Building Science http://www.greenbuildingadvisor.com/articles/dept/building-science/what-exactly-low-load-home

The Important Stuff You Need to Know About Ceiling Fans

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Here are a few basic principles that many people don’t understand

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Here we are in the middle of air conditioning season.  So why don't we chop down some myths and misconceptions about ceiling fans?

What got me on to this topic was a video of a fan with blades that hide on top of the fan when the fan is turned off. Sounds clever, but it's a ridiculous idea.

Anyway, here are seven things about ceiling fans that a lot of people seem not to know.

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from Building Science http://www.greenbuildingadvisor.com/articles/dept/building-science/important-stuff-you-need-know-about-ceiling-fans

An Update on the Residential Ventilation Debate

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Here’s what you missed at the ASHRAE 62.2 committee meeting last week

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It's been a while since I've written about what I had been calling "The Great Ventilation Debate" back when Joe Lstiburek was battling the ASHRAE 62.2A standard for residential mechanical ventilation systems established by the American Society of Heating, Refrigerating, and Air-Conditioning Engineers. Among other requirements, the standard requires a home to have a mechanical ventilation system capable of ventilating at a rate of 1 cfm for every 100 square feet of occupiable space plus 7.5 cfm per occupant. residential ventilation committee. The 62.2 committee meets in person twice a year at the two ASHRAEAmerican Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE). International organization dedicated to the advancement of heating, ventilation, air conditioning, and refrigeration through research, standards writing, publishing, and continuing education. Membership is open to anyone in the HVAC&R field; the organization has about 50,000 members. conferences, and they just met last Friday and Saturday in Houston, Texas.

A few things have happened over the past few years, so let me give you a brief update.

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from Building Science http://www.greenbuildingadvisor.com/articles/dept/building-science/update-residential-ventilation-debate

Do Solar Panels Need to be Cleaned?

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How the accumulation of dust, pollen, and bird droppings affects the energy production of a PV array

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I was at my brother’s house in Lee, New Hampshire, recently and looked up to see that his 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.) panels looked a bit dull (see Image #2 below). His PV array is easy to get to — the long north slope of his roof has a walkable 5:12 pitch — so we went up and took a closer look.

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from Building Science http://www.greenbuildingadvisor.com/blogs/dept/building-science/do-solar-panels-need-be-cleaned

Simple Steps to Improve Air Conditioner Performance

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If your air conditioner struggles to keep up in the heat, these measures can help

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It's getting hot out there. Here in the Southeast, we love our air conditioning.  In fact, without air conditioning, far fewer people would live in places like Houston, Hattiesburg, and Sopchoppy. And that's true for the hot, dry places, too, like Phoenix, El Paso, and Boron.

So if we're going to have air conditioning in our homes, we want it to work.  It should be effective and efficient.  It should keep us cool without creating new problems, such as excessive noise, bad indoor air quality, or comfort that varies from room to room.

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from Building Science http://www.greenbuildingadvisor.com/articles/dept/building-science/simple-steps-improve-air-conditioner-performance

Phenolic Foam Insulation Revisited

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Can we put to bed the corrosion concerns with this insulation?

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A particularly well thought-out and thorough question from longtime GBAGreenBuildingAdvisor.com reader Aaron Birkland on the pH of phenolic foam and its possible corrosive nature prompted me to follow up my original blog on Kingspan’s Kooltherm rigid insulation.

Aaron has two main questions:

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from Building Science http://www.greenbuildingadvisor.com/blogs/dept/building-science/phenolic-foam-insulation-revisited