May, 2012
Feature
Inspection News and Views from the American Society of Home Inspectors



A Reasoned Indictment of the Green Movement

CHARLES BUELL, ACI

GreenCover.jpg

My building career started in 1971. Four years later, a developer wanted me to build a house in a development he owned. He showed me the plans; I politely said "no." I said if I were to build a house, it would not be another dinosaur of which there were already too many. At that time, we were in the throes of the first energy crisis, and I had joined a small movement of people who were looking for ways to save energy.

In hindsight, the worst thing that could have happened to this country was that this first energy crisis artificially went away. People were lulled into thinking they could go on using energy as they were accustomed to, and the interest in conserving energy in the 1970s was the root of what is known today as the "green movement."

A few days after I turned down the owner of the housing development, he called to ask what kind of house I would like to build.

So began my career of designing and building passive solar/super-insulated homes in upstate New York. That first house was relatively simple; not much different from today's requirements for house construction. I oriented it to take advantage of the sun. The roof was pitched so solar collectors for water heating could be added later. The greatest percentage of glazing was on the south side. The walls were 2"×6" construction (unheard of at that time) and were insulated with cellulose fiber insulation. Thermal mass was built into the floor system to absorb the sun.

By 1978, I was building walls with 2"×8"s and the foundations were all Pressure-Treated Wood systems. It is the use of wood foundations that precipitated what, at the time, was considered a major breakthrough in creating remarkably energy-efficient homes — at less cost than a conventional 2"×4" house of the same size/volume. This breakthrough largely fell on deaf ears, but I had the great fortune of attracting a few buyers who wanted such a home. I consider myself lucky to have had clients who shared my dream of more efficient homes.

Syracuse University routinely brought students through these homes as part of their educational experience. Some skeptics claimed I was lying about the performance even when the utility bills were in plain view.

In 1979, a small duplex (800 sq. ft. on each side) won a $10,000 New York State Energy Research and Development Administration (NYSERDA) grant and was featured with 16 other homes in the book "1979 NYSERDA Passive Solar Design Awards."

solarhome1.jpg
solarhome2.jpg
Buell House illustrations above are reprinted from the “1979 NYSERDA Passive Solar Design Awards Publication,” produced by the New York State Energy Research and Development Authority, a public benefit corporation chartered by the New York State Legislature. In 2009, NYSERDA performed an analysis of two “passive” design homes built by Bruce Brownell of Adirondack Alternative Energy.  The findings of this report generally are consistent with that of  the 1979 article except for the additional consideration that mechanical ventilation assisted with energy recovery for better moisture management is recommended for today’s tighter building envelopes. The entire report can be found here:  http://www.nyserda.ny.gov/Page-Sections/Research-and-Development/~/media/File/EIBD/Residential%20Buildings/aae_report.ashx.

There is a huge, glaring inaccuracy in the information about this home in the book. It says the home was heated by an oil furnace. The actual heating system was a hydronic-baseboard system with two zones on one 30-gallon electric water heater.

ERDAawardhoiuse-1024x668.jpg
The award winning passive solar duplex in Oswego, N.Y., designed  by Charles Buell in the late 1970s.


Selling something different


Part of the problem with trying to sell something different is that if industry cannot find a way to make money from it, the advancement is greeted less than enthusiastically. In those days, we saw it with active solar systems — both for air heating systems and photovoltaic systems. The solar panel manufacturers did the hard sell on payback and how the technology would improve soon such that every house could afford it. Forty years later, we are still hearing about how technology is "almost there." If the house is energy-inefficient, the payback on these systems would probably pencil out. In new construction, with proper levels of insulation and other design elements, they would never pay for themselves. And, when thinking green, we might want to take into account the environmentally unfriendly processes of making solar panels.

Looking at payback

If an active solar heating system costs $24,000 and is able to achieve 75 percent of the house's heating needs of $2,000 per year, the payback would take something like 16 years. Let's take a similar-sized home and: 1) insulate the heck out of it; 2) orient it to the sun; 3) decrease the windows on the east and west sides; 4) eliminate windows on the north side; 5) provide an insulated foundation system; and 6) put a $10,000 active solar system on it. We now can get 75 percent of our heating needs, but our annual heating costs will be only $250 and the payback becomes more like 30 years, plus the panels likely would have to be replaced, adding at least another $10,000 to the cost.

My point is that the more efficient the home, the less economy there will be in using technologies that will never pay for themselves.

Passive techniques to increase efficiency

So, the current beef I have with today's new green movement is that it is the same as the old green movement. We are attempting to fix something with technology that has little real need for technology.

I am going to go out on a limb here and say that the majority of what we need to do to create energy-efficient homes in this country can be done passively, with little complicated technology and more emphasis on conservation. Houses don't have to look different, and, most importantly, they don't need to cost more. In some cases, they could cost less than conventionally built homes.

Payback for a less-costly house

Instead of fighting with today's green movement, I will describe how we can move forward using existing construction techniques with readily available resources that are sustainable. This approach does not increase greenhouse gases in the process of making the technologies necessary to go down the path promoted by some green-movement advocates.

Please know I am not against technology. A lot of my ideas could be improved by using some of the technologies we have now and others being developed. I believe appropriate use of technology will save us on this planet, but it is critical to use it wisely, not create problems that were not there to begin with.

Getting down to the basics

If I could show you how to get a house to where it needed 75 to 85 percent less energy to heat and cool it, and to do so by simply using conservation, super-insulation, air-stopping, advanced-framing techniques and house orientation, would you become a believer? Well, my experience has proven this is possible. Depending on where the house is built, it can be possible to eliminate heating and cooling systems altogether.

The basic principle is so simple that it makes high tech companies cringe and skeptics scratch their heads. No gadgets — no gimmicks — just working with Mother Nature to get us to where we want to be: Cool in the summer, warm in the winter — and not having to sell our first-born to do it.

Think of a house as an insulated bubble sitting on the ground. Now, take that insulated bubble and extend it deep enough into the ground to be well away from the depth of frost — say basement height. It is important that this basement wall be as heavily insulated as the bubble above ground is — or slightly less. Inside this insulated bubble, the ground temperature of the concrete slab floor will be in contact with earth, which stays at a constant 50 to 55 degrees — depending on what part of the country you live in. Of course, once we add heat to our bubble, the floor will warm up a bit and, once carpeted, won't be uncomfortable.

bubbledrawing5.jpg

We only have to heat our bubble from the constant ground temperature of 50/55 degrees Fahrenheit to our desired indoor temperature of 68/70 degrees Fahrenheit, instead of from whatever the ambient temperature is. If you live in Minnesota, that temperature might be minus-30 degrees Fahrenheit — a 100-degree difference instead of a 20-degree difference. We actually can start to use some of the waste indoor heat from appliances, lights and human activity to chip away at that remaining 20-degree difference. Adding contributions from solar gain and appropriately placed windows, we chip away at it even further.

This is how we are able to go from a heating bill of $2,000 a year to $250 a year. The dollar amounts I'm using in these analogies are accurate in terms of percentages, but are used only to demonstrate the differences, not to represent actual situations — although they could.

In cooling, the same principles are at work. With a mechanical air conditioning system, the goal is to have the indoor air about 75 degrees max. Even if we achieve 80 degrees, it will feel comfortable when it is 110 degrees outside because the inside air is a drier heat. In the super-insulated house, when it is 110 degrees outside, the floor temperature still is 50 degrees; therefore, we need merely to circulate the air throughout the house to easily maintain temperatures well below the target temperatures of the mechanical air conditioning system.

Thinking about that bubble in terms of what real construction would look like, keep in mind that the passively efficient house is a system. The whole house must work together to get us to where we want to be.

HOW TO BUILD A HOUSE

The drainage system:
The first and most critical factor is drainage. If the drainage system is not carefully planned and executed, misery will be the result.

The building site:
On site, the house must be oriented to take advantage of the sun and additional considerations such as wind, nearby water, trees and others too numerous to cover in this article.

The foundation:
The foundation will be Pressure-Treated Wood framed with 2"×8" studs minimum. It sits on a 12" bed of pea-gravel that extends the entire width of the excavation. This excavation is drained away by gravity.

Frankly, if it cannot be drained by gravity, it should not be built at that location.

Slab-on-grade installations are possible as long as the insulation extends deep enough into the ground to achieve the desired use of the constant ground temperature. Sump pumps should never be relied on for foundation drainage. The house deck is constructed on the foundation walls; then the basement floor can be poured over a double 6-mil vapor barrier. The concrete slab not only creates the basement floor, but because it is poured against the bottom of the wood foundation, it prevents the walls from kicking in after the wall is back-filled.

Typically, excavated soils are not to be used for back-fill. Crushed stone is preferred and the excavation is filled up to finish grade. This continuous bed of gravel under the slab and up the outside of the foundation provides adequate drainage and passively vents radon gases that might otherwise find their way into the home. Unless someone plugs the end of the drainage pipe, water typically would never approach the bottom of the foundation or the foundation walls — even though this particular type of pressure-treated lumber is rated to be submerged/buried.

While I like the idea of concrete foundations, I never have been able to find a way to make them pencil out in the context of building super-insulated homes. Insulating a concrete foundation to R-30+ is costly and there is the problem of interior wall finishes unless one is happy with the look of concrete and surface-mounted wiring. I like the idea of having all that thermal mass as a heat sink, but thermal mass can be added quite effectively by covering the walls with double 5⁄8" drywall. Wood foundation walls come ready to wire and plumb and to install finish materials as needed.

The house envelope:
The house walls are constructed with 2"×10" top and bottom plates and the studs are made of trusses. A typical stud for a one-story house is made by ripping a 2"×4" in half and gluing and nailing a plywood zigzag on both sides. One of the big problems with conventional framing is that so much of the wall — up to 25 percent of it — is solid wood. In other words, 25 percent of it is crappy insulation to go with the windows that also are crappy insulation. Current insulation requirements for sidewalls are about R-21.

With a truss-type wall, we can get up to R-40 with only about 5 percent of the wall being solid wood. The headers can be made out of plywood glued and nailed on both sides of a 2"×10" (1⁄2" ripped off to maintain framing lines). These headers can be blown full of insulation as well. It goes without saying that all interior windows will have insulated, folding-type shutters with a minimum R-value of 10.

Supports for the headers are dimensional 1"×10"s instead of  2"×10"s — further reducing the amount of solid wood through the wall.

Raised-heel roof trusses are used. In other words, a uniform thickness of insulation is maintained across the entire attic space from eave to eave, covering the entire wall top plate to a depth of a minimum of 16 settled-inches of blown cellulose insulation—R-60.

For most of the country, we're still stuck at R-38, although in Zones 6 and 7 it has been raised to R-49 in most jurisdictions. Based on my experimental work in the early 80s, I believe requiring R-49 in the attic is way out of sync with requiring R-21 in side walls. And, cost benefit ratios will be skewed.

Some will argue that 16 settled inches of blown cellulose insulation to an R-60 will never pay for itself. But these are the same people who want to sell me solar panels and other high-tech gadgets that truly will never pay for themselves, or they are not seeingthe cost of the home being a sum of the whole.

One more expensive component is offset by a cheaper component. Insulation is one of the cheapest single components of the home, and if it helps me eliminate the need for a 120,000-BTU furnace, I will argue for the extra insulation.

In the first year of the life of the house, the reduced heating costs easily will pay for the extra insulation. I avoid using meaningful dollar amounts in these analogies because the costs of things change so rapidly, while the principles do not. In a very real sense, comparing older homes with super-insulated homes is a little bit like comparing apples and oranges. Once we cross into the world of super-insulated, we are in a Brave New World with its own advantages and rules, and figuring out the cost benefits and comparisons with conventional homes is of limited value.

Cellulose fiber insulation is by far the most economical way to get us where we want to be in terms of thermal efficiency and minimizing air infiltration. Fiberglass — regardless of type — should not even be considered in the construction of modern homes. Newer Icynene foam insulation shows promise, but the material's expense will push the initial cost of the home a little higher.

When I was building energy-efficient homes, the biggest headache was finding heating systems small enough to do the job. Forced-air furnaces in the 8,000-10,000 BTU range would have been ideal, but they did not exist. Probably, still do not exist. Today, we have great alternatives, such as individual room heat pumps. These types of units would have been perfect for the super-insulated homes I built in the 70s and 80s that had heating requirements between 3-5 BTU per square. In those days, I was stuck with 30-gallon water heaters and hydronic radiators — or electric resistance heaters. To put this in perspective, a typical 1,500-square-foot home that is built this way comes close to satisfying its heating requirements with a hair dryer and one kid chasing the dog around the inside.

Photos of the drainage, foundation and framing
for super-insulated homes built in the 1980s.


house2.jpg




Left: The drainage trench for the gravel under a wood foundation system.
















house1.jpg
Above: The gravel was leveled to a depth of 12 inches for the house foundation to sit on. The foundation panels can be seen in the background.


house3.jpg
Above: Truss-type studs and advanced framing methods for passive solar/super insulated house.

house4.jpg
Above: 2"x10" truss studs, insulated headers, hollow corners, 1/10 jacks and cripples.




Why aren't we building passive solar/super-insulated houses?

So, yes, it can be done. Why aren't we building houses like this all across America? I believe because of misinformation and disinformation about what it means to be truly energy efficient. And, if there are people more interested in making money than in saving energy, there will be charlatans running around in green costumes. As long as homebuyers want 6,000 sq. ft.-homes, there will be people ready to assure them that their 6,000 sq. ft.-home can be built green. In my opinion, 6,000 sq. ft. and green is an inherent contradiction and only adds to the problem. If we learn to save $1,750 on our heating bills only to justify spending more money on a bigger house until we get back up to that $2,000 dollar cost for heating, what have we really gained?

And this question is apart from the additional resources consumed to build that bigger and better house. What we, as individuals, can afford must always be tempered by what the planet can afford.

Perhaps the real green is jealousy?

Are we jealous of the person who has more? Because someone else has more, are we entitled to have more, too? The road to ruin is paved with green intentions.