This will need to be a series because the topic is too large for a single post. Lets start with housing and break it down into two parts. This is Part 1 Building Shell.
I am 64. I have been preaching about climate change since 1971 when I was 14. I am frustrated and pissed off, but also informed, having followed both the science behind the problem and the science behind the solutions for 50 years.
Building codes in the US are a joke. In 2009 while studying to be an energy consultant I learned that the best “Energy Star” rated standard in the US did not meet the minimum energy code in Europe. In fact some of our building codes prohibit the best practices available. The technology exists to build homes that need no heating system anywhere in the continental US. Its called insulation.
While the details can get complicated, in concept it really is that simple. Since heating systems are expensive to install and maintain, much of the added cost of insulation is covered by the elimination of the boiler or furnace and heat distribution ducts or pipes. Once the building shell is efficient enough, the lights appliances and people keep the building warm. During the cold season, if it gets too warm, cooling is free, just bring in some outside air.
This is not to be confused with net zero homes. If you start with a horrible building that guzzles energy and put a big enough solar array on it to cover the use, it qualifies as net zero. Despite the obvious stupidity of this, it is done. The problems are many.
Heat waves cause us to run the AC. This uses power, which for most of us still means producing CO2. Which intensifies the heat wave. The technology to reduce this vicious cycle already exists. It’s called ……. insulation.
Insulation is a fairly new technology. 100 years ago homes were built with hollow cavities. It was not until the 1940’s that home insulation became common place. While insulation technology has evolved and improved over time and our understanding of it and ability to model its performance mathematically has skyrocketed, our actual use of insulation has not kept pace. Why is that? It is because we focus on short term economics and not the environment. So what exactly are the economics?
If you hate algebra skip this paragraph. Lets assume the heat loss of a house is X and the cost of insulation is Y. If you double the insulation the heat loss is now .5X and the cost of insulation is 2Y. From the first doubling Y dollars yield a savings of .5X. So what happens if we repeat the process. The cost of doubling the insulation is now 2Y for a total of 4Y dollars spent on insulation. And we cut the heat loss to .25X. The first extra Y spent on insulation yielded a .5X savings over the original cost but the second time 2Y yields .25X savings in heat loss. This is a cost benefit of ¼ the first doubling; and it gets worse each time. In economics this is called the law of diminishing returns.
When energy was cheap, the idea was to hit the “sweet spot” and not over insulate because it cost less to heat than the interest on the cost of the increased insulation. This is very short sighted, but was considered gospel truth. It assumes 3 falsehoods.
1. Energy will never increase in price.
2. Interest rates will never change.
3. Emissions are externalities that don’t matter.
Energy prices have increased dramatically, interest rates have been all over the map, and those inconsequential emissions are now threatening life as we know it. The problem is that while everybody has acted on the conventional “wisdom” (stupidity) nobody seems to remember the why behind it and realize that the assumptions are all wrong so the entire idea needs to be scrapped.
Most heating systems are active. They burn fuel and electricity and produce heat that is lost to the environment. The equipment wears out and must be replaced and the beast must constantly be fed money. Insulation is passive and will last the life of the building. It does it job day in and day out with no fuel or electricity. It more closely resembles a cornucopia than a heating system.
A few closing thoughts on building shells to help you make wise decisions for yourself. The #1 most important part of reducing energy consumption is air sealing. If you doubt this, try heating your home with the windows and doors open. Insulation does nothing if cold air by passes it. Adding insulation on the outside can rot your sheathing unless it is done right. Consult an expert who can model the temperature gradient through the wall and make sure you are not hitting the dew point. A good rule of thumb is 4” of foam is almost always safe, but less is questionable. It all depends on where you live.
Windows rarely save much energy. Buy new windows when you NEED new windows but don’t fall for the hype of the windows salesman. Unfortunately, the number of contractors hyping savings is inversely proportional to the savings. #1 Air Seal. #2 Insulate #3 upgrade the heating appliance to one of higher efficiency. Last and least replace windows. Now go find and ad for #1 Air Sealing. Good Luck!!
All this technology and know how exists today. Although there may be additional breakthroughs and advancements in insulation technology, no breakthroughs are needed. The problem is human inertia, ignorance and lack of political will. The only Silver Bullet needed to implement this piece of the climate solution puzzle is the political will to update and enforce building codes.
We need to radically rethink housing. For full disclosure I am a landlord, but most of my tenants really like me. In fact I often don’t have to advertise because tenants refer their friends. My units all come with LED’s preinstalled. It doesn’t save me any money, but it saves my tenants money and makes me more popular. Most importantly, it reduces the wear and tear on our mother earth.
Part 2 will be powering the home.
Daniel E. Michelsen