The 2021 Energy Vanguard Wrap-up
Here we are at the end of another year. It's been a weird one! I certainly won't go into all the weirdness of 2021, but let me give you the Energy Vanguard wrap-up, divided into five categories. Four of them…
indoor air quality
3 Important Facts About Dew Point Temperature
That photo above is the bottom side an air conditioner in a crawl space on Hilton Head Island, South Carolina. Those droplets tell us something important: A property of the air in that crawl space aligned with a property of…
Bad Advice About Indoor Humidity in Cold Weather
It's that time of year again. The cold weather has begun here in the Northern Hemisphere, and people are talking about raising the humidity of the indoor air. I'm certainly no fan of bone-dry air, having experienced too much of…
6 Options for Ventilating Homes in Humid Climates
Ventilating homes in any climate has its challenges. In Duluth, Minnesota, it's the extremely cold weather in winter, which leads to extremely dry air when you bring it indoors. In Phoenix, Arizona, it's the extremely hot weather in summer, which…
Why You Probably Need an ERV, Not an HRV
One of the most frequently asked questions regarding the type of balanced ventilation devices known as the energy recovery ventilator (ERV) and the heat recovery ventilator (HRV) is: "Can I get that in red?" OK, not really. Everyone knows that…
Measuring the Efficiency of a Room Dehumidifier
A few months ago, I wrote about the confusing world of dehumidifier capacity. That quantity tells you how much water a dehumidifier will produce in a given amount of time. Here in the US, we use pints per day, but…
We Need Higher Ventilation Rates. But How High?
The COVID-19 pandemic has changed a lot of things, including my view on higher ventilation rates. A few years ago, Joe Lstiburek of Building Science Corporation pushed hard for lower ventilation rates. He believed ASHRAE's residential ventilation standard (62.2) resulted…
Home Performance Tools on Amazon Prime Day
In case you haven't heard, Amazon is having its Prime Day sale today and tomorrow. Occasionally, I write about tools and products we use in our work or homes and provide affiliate links* to the ones we like. I've also…
Can an Exhaust Fan Control Humidity in a Spray Foam Attic?
Here in the South, we love our humidity. It makes us glisten in the summer. But we also love our air conditioning and low humidity inside our homes. To save on air conditioning costs, more and more homes have attics…
The Confusing World of Dehumidifier Capacity
Dehumidifiers have one job: to turn water vapor into liquid water by moving air over a cold coil that's below the dew point. The capacity, or size, of a dehumidifier is just the rate at which it does that conversion. …