# heat loss

### Marc Rosenbaum Offers a Free Online Lecture

Heat loss from basements and slabs to the ground is complicated. If you're interested in learning more on the topic, you might want to take advantage of a free lecture being offered by energy expert Marc Rosenbaum. At 1:00 p.m. on Thursday September 4, 2014, Rosenbaum will offer a free online lecture on heat loss to the ground. The presentation is intended for architects, builders, and others who want to have a better idea about how buildings interact thermally with the ground and how to calculate heat loss to the ground.

### Heat Losses Are Way More than Planned

Bob Holodinsky was hoping for a better outcome from the heat loss calculations he received for his new Peterborough, Ontario, home — calculations that appear to have upset his plans for heating with a ductless minisplit. "I thought I was on the right track," he writes in a Q&A post at GreenBuildingAdvisor, "but now I am not so sure."

### When Do I Need to Perform a Load Calculation?

In my last three blogs, I discussed the basics of heat-loss and cooling load calculations. The unfortunate truth about these calculations is that fast methods aren’t particularly accurate, and accurate methods require making measurements, checking specifications, and entering data into a computer program — in other words, a significant investment of time. So how should builders go about making these calculations?

### How to Perform a Heat-Loss Calculation — Part 2

To continue last week’s discussion of heat-loss calculation methods, let’s consider a simple rectangular building, 20 feet by 30 feet, with 8-foot ceilings. Let’s assume it has an 8-foot-high basement with uninsulated concrete walls; the below-grade portion of the basement is 7 feet high, with 1 foot above grade. To keep things simple, we’ll assume that the house has a flat roof, and that each side of the house has two windows (each 3 ft. by 4 ft.) and one door (3 ft. by 7 ft.). The house doesn’t have a chimney.

### How to Perform a Heat-Loss Calculation — Part 1

I’m going to devote the next several blogs to a discussion of heat-loss and heat-gain calculations. These calculations are the first step in the design of a home’s heating and cooling system. In order to address this big topic in little bites, I’ll start by discussing heat-loss calculations. I’ll get around to heat-gain calculations and cooling equipment in a future blog.