Letters: July/August 2011

A version of this article appears in the July/August 2011 issue of Home Energy Magazine.

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Retrofit Insulation for Concrete Slab

What products or materials do you recommend to put on top of an on-grade concrete floor before laying flooring, and so on, to turn a basement into real living space? Decent thermal insulation would make the space much more comfortable, as would a good moisture barrier. It might reduce any radon infiltration as well. However, it’s about 30 years too late to put foam insulation under the slab!

Peter Gollon
Energy Chair, Long Island Sierra Club,
Long Island, New York

Technical Editor Steve Greenberg replies:

Regarding the topic of retrofit insulation on an on-grade slab, I have a couple of thoughts:

• It should be closed-cell foam for maximum thermal and water resistance.
• If you put a floating floor over it, you might get away with just rigid foam on the concrete and the floating floor over that.

Much depends on the ability of the insulation to keep the slab dry enough; also on how much of the space you are willing to take up with the insulation and flooring. You could always use the same insulation that would have gone under the slab and then pour a topping slab over that, for example, with tubing for a radiant floor.
 

Turn the Water Heater Down

In the article, “Combustion Appliance Testing: Why, How, When?” (Nov/Dec ’10, p. 38) it says, “Turn the water heater down and the furnace off if conditions allow; mark settings.” Why do you do this during the CAZ test?

Dean Zias
Project Manager, Multifamily Apartment Buildings
New York State Energy Research and Development Authority
New York, New York

Author Tamasin Sterner replies:

The reason for turning down the water heater and turning off the furnace during the combustion appliance zone (CAZ) worst-case conditions testing is so the water heater and furnace don’t fire while the technician is depressurizing the CAZ and measuring the pressure in the CAZ with reference to the outdoors. If the water heater or furnace fires while the technician is sucking air out of the CAZ with exhaust fans, flue gases could come down the flue pipes and chimneys due to duct leakage and other pressure imbalances. Then these fumes are in the CAZ, which is bad for the technician and possibly the residents. 

If the flue gases do come down the chimney, the technician will discover this when he or she does the spillage test (which is done after measuring CAZ depressurization but while the CAZ is still under the most negative pressure). The technician will also test to be sure the draft pressure in the flue is strong enough. If the water heater or furnace fails the spillage or draft pressure test, the technician will take the CAZ out of the most negative pressure conditions (turn off the exhaust fans and maybe other modifications) and check for spillage and then draft pressure again. This is called testing under natural conditions. The technician will follow action steps if one or more tests fail.

Spillover Is Good

I recently read the article by Shaun Hassel, Ben Hannas, and Michael Blasnik “Energy-Efficient Homes: Predictions, Performance, and Real-World Results” (Jan/Feb ’11, p. 28).

I applaud Home Energy for including an article on evaluation! I would like to see more types of articles like this where real-world results are provided (rather than relying on engineering estimates of energy savings).

However, I do have one concern. In their article, they state: “Spillover, then, can make a program appear to have less impact than it is actually having.”

At face value, this is correct. However, spillover is an important element of many energy efficiency programs, especially those programs that are focused on transforming the market for energy efficiency. If regulators and others accounted for the savings from spillover, these programs would be valued more highly than they currently are—and their savings (direct and spillover) would be greater than currently reported.

Edward Vine
Staff Scientist
Lawrence Berkeley National Laboratory
Berkeley, California

Blair Hamilton (1949–2011)

Diagnosed with non-Hodgkin’s lymphoma in 1991, Blair Hamilton passed away on April 8, 2011, at the age of 61. Best known for having founded the Vermont Energy Investment Corporation (VEIC) and Efficiency Vermont, Hamilton was a visionary who was dedicated to
the environment.

Scott Johnstone, executive director of VEIC, said in a recent interview that Hamilton’s idea of starting a company in 1986 that would focus on lowering the cost of energy was unprecedented. “The fact was there just weren’t a whole lot of people who wanted to pay for that, or see that happen at the time,” he said. Now, 25 years later, VEIC is a private nonprofit with 200 employees, $38 million in annual revenues, and satellite offices in Ohio, Boston, and Washington, D.C. But Hamilton received much recognition in his lifetime. Among many other honors, he was named the Champion of Energy Efficiency in 2002 by the American Council for an Energy-Efficient Economy.

Over the past 20-plus years, Hamilton also did a whole lot for the efficiency community. This included seeing to the installation of at least 30 million efficient light bulbs, according to his obituary, which was published on April 11 in the Burlington Free Press.

“Blair was a visionary, a friend, a genius, and a mentor to all of us,” Johnstone says. “He left an indelible mark on the world, and he’ll be greatly missed.”