Big Steps in Building: Change our Building Codes from Relative to Absolute
by Lloyd Alter, Toronto on 08.27.07
For at least 3700 years, since the code of Hammurabi, builders of houses have had building codes, a government minimum standard intended to protect the health and safety of its citizens. Possibly in all that time, the majority of builders have considered it the maximum as well- don’t do any more or build any better than you have to. Through the energy crises of the 70's to today, energy efficiency standards kept going up, but the amount of energy used in a house went up faster because they just keep getting larger.The average post-war 1950’s house was 983 square feet; by 1970 it was 1500 SF; last year it was 2350. Encouraging smaller homes, like smaller cars, would save a lot of energy, but codes applies the same standard across the board. Just as conservation is a resource, everything we use in housing has embodied energy, a carbon footprint and an operating cost; we have to treat them all as resources where we can mine savings of energy and greenhouse gases.
Monster Homes: Enough is Enough
But how? If we keep raising the relative efficiency, costs go up for the people who can least afford them. Perhaps we need an absolute performance standard for building codes, with maximum resources allocated to each house; a standard that a normal family can afford to live with, yet gives builders and homeowners the opportunity to build larger or differently if they want. Lets look at how this affects various resources:
Heating is a resource: Why shouldn’t the purchaser of a monster 5,000 footer have to insulate it twice as well as the buyer of one half the size? Let’s make the standards for consumption vary according to size to make affordable housing cheaper and larger houses more efficient. Commenter Tom noted in another post: “ it's become increasingly clear to me that our traditional building energy codes that only measure RELATIVE EFFICIENCY are just not getting the job done. It's the ABSOLUTE CONSUMPTION of our increasingly obese building stock that is the real issue.” He also pointed out that “Marin County now has an interesting "Big 'n Tall" ordinance which states that no new home may use more NET energy than a home that is a maximum of 3500 square feet (basically if you want to build bigger you have to add solar PV to offset). “ (Download Marin County bylaw pdf here)
Let's change our building codes to permit a specific amount of energy consumption, period. If you want to build a house twice as big as, say the design consumption of a 2500 footer, you have to double the insulation in the walls or cover the roof with photovoltaics. If you want a six burner professional stove, add some more insulation still.
This shouldn't affect the rich; they can afford the insulation. It will help the poor; small houses can probably have even lower levels of insulation than they do now. It may hurt the middle-of the road suburban McMansions, but they are dinosaurs anyways.
Cooling is a resource: almost all cooling is electric, and almost every suburban house comes with it standard. Every suburban house also seems to come standard with big jazzy windows that look great on the renderings (and only have small openings for ventilation); open yards without trees, and walls of thin materials that have no thermal mass. Let’s have a building code that demands cross-ventilation, control of solar gain and trees- if you want to build a house, make it part of the code to plant big deciduous tree to shade it in the summer. Trees, awnings, a white roof; it doesn't matter as long as the house does not exceed the performance standard set, the maximum tonnage of cooling a house is allotted.
Land is a resource- Building a house is not an isolated event, it happens in a framework of land development and urban planning. Increasing the efficiency of a house by 20% doesn’t do much in the larger scheme of things if you build 5,000 square feet an hour’s commute from work, and if getting a quart of milk requires a 20 minute drive. It is all a bigger picture- the design of the community, the frontage of the lots, the ability to walk to school or to a decent transit system, these are the things that really influence energy use. Let’s have a building code that sets a minimum density for development and a maximum distance to shopping or transit to reduce the amount of land lost and fuel used for transport.
Building Materials are Resources- yet our houses are built of cheap, unsustainable and possibly dangerous materials. Let’s have a building code that insists on healthy materials, and get rid of formaldehyde and vinyl and VOC laden finishes. Danger increases with concentration and quantity; lets put absolute limits on how much can be allowed per family. The smaller, less expensive house could use the cheaper materials while the monster would have to pay a little more for higher quality, but both would have the same absolute exposure.
Lets make the building code a planning document, encouraging tighter, more efficient designs, walkable communities and smaller, not bigger dwellings. Let’s demand cross-ventilation, control on window size, placement and shading to reduce the need for air conditioning. Let’s build smaller but build better and build to last.
Let’s take the building code and change it from a legal minimum standard for a development industry out of control and make it a guide for what we want to build when we want to conserve all of our resources, not just energy.
This post is based on an article I wrote for On Nature Magazine.
I would think it would be possible and highly desireable to have building codes require solar hot water heating and solar photovoltaic panels for houses above a certain square footage, and base the amount required on how much larger the house is.
This would be a pretty small percentage in terms of purchase price for such a large home, so would not financially burden those on the lower end of the housing spectrum.
Very interesting article, and the graphic on the front page is so clear.
I suppose this rapid increase has been traditionally seen as progress, along with bigger cars, more travel etc. To change to an absolute measure seems the logical conclusion of our knowledge of environmental problems. If this was taken internationally....there would be serious 'readjustment'!
I think the market will drive much of the "Bigger is Better" mentality. Remember that the boomers will retire soon, and when they do, they will realize that their suburban neighborhoods generally don't support walkable lifestyles that so many elderly Americans desire. Look at the growing urban loft and condo markets. Cities are in and the McMansions are out. Those huge houses won't have buyers, for credit reasons, transportation fuel price reasons and home energy reasons. Remember beanie babies? everyone thought they could invest in them because there would be a market. McMansions are going the way of beanie babies: too many on the market and not enough buyers. The market will correct this, and we might just see huge wastelands of huge homes a huge distance from anywhere except huge Walmarts with huge populations of workers that can't qualify or afford the huge houses. Huge mess. Small urban homes will be on the rise, and markets will support them.
Great Post. Smart initiatives. I think Lloyd is onto something here. I live in a converted 100 year old mansion, with 3 other families. In fact, the entire area I live in used to be all mansions close to downtown- now they are rapidly converting to multifamily apartments. Baby boomers, as well as green thirty somethings are moving in, due to the charming feel, friendly neighborhood, and a close walk to downtown. Change is on the ground, and it simply makes sense to those of us who don't want the 45 min commute, or the isolation of suburban life. The renovated mansions are probably some of the best apartments in town. Focus on growing larger densities closer to the city activities has it's own unique challenges, but is increasingly worth the effort.
I've been thinking along these lines for awhile, but why limit the control of energy and resources to new home construction? Why not give every household a yearly energy budget that includes all energy use? Want to drive a Hummer? No problem- better have a super efficient house with photovoltaics. Want a 6,000 SF mansion? Better start riding your bike to work.
People should be able to buy and sell energy credits as well. That way a low income family living in a one bedroom apartment with no car can earn some extra money selling energy credits to the wealthy.
Judging by the rate of growth on the first chart, my 1,250 square foot house must have been huge when it was built in 1900!
Victorian houses were pretty big.
Overall, great article.
My only problem (unlike MY), was the front-page graphic. It's misleading because the area of the 2000 house was roughly four times that of the smaller, 1950 house (each side of the larger was roughly twice as long as the smaller), but the areas in square feet had only doubled. While a good lead-in to the article, the graphic at best conveys little information (it could be replaced by a three line table), and at worst is deceptive.
Lloyd's reaching out for the third rail on this one, but he's asking tough questions we need to be asking.
I actually like the 'houses like Matryoshka dolls' graphic; they dramatize the point so well. I honestly can't see how anyone could be mislead or mistake them for area charts, the data's all right there.
Yes Charles is right - a little AutoCad (man I hate that program) showed that the outline for the 1970 house has increased it's area by 2.2 times, which is the increase in square foot for the 2000 house.
But if the article is about square feet of floor, and we imagined each house has the same length, then the graphics would be correct! And in fact the 2000 house should be even bigger! Residents of the 1950 house would have been hitting their heads on the ceiling...
Maybe a plan view of the houses would have been better!
Victoria, Australia legislated for minimum 5 star standards in new housing about 5 years ago. This 5 star rating is based on a relative code assessment (watts per square metre per annum) which has since been found to display the faults mentioned in Lloyd's article. A recent state government review here has indicated that the absolute per-dwelling energy use for an average house in Victoria has increased by approximately 15% since the legislation was inroduced. This is partially due to housing obesity, and partially to do with some faults in the rating system (including not taking energy usage for lighting into account.)
To make matters worse, this increase in energy usage per dwelling does not take into account the reduced number of people living in each dwelling (the trend toward smaller families and more single occupants is similar in Australia to that in the US), which means that the average rate of housing energy use per person would have increased even further.
I generally agree with Lloyd's thesis: if total energy use has to decrease, we need to either legislate for absolute standards (which carries some political risk for legislators, as it targets the wealthy and more politically connected) or make the cost of energy increase sufficiently (through carbon trading, a carbon tax or similar) to provide an market disincentive to energy wastage (which has its own social inequity risks).
I like this idea. I am an urban planner and bang my head against the wall frequently about building codes and how difficult they make it to do green development sometimes. Definitely something to think about.
I would like to add though that I don't know if this scheme would help the poor.
("It will help the poor; small houses can probably have even lower levels of insulation than they do now.")
In the northern hemisphere insulation is very important and energy poverty occurs regularly for those in the lower classes. I know of people who pay more in heating bills in a month than they do in rent. We should be increasing the mandatory amount of insulation in ALL homes so that they are more affordable in the long run. The capital cost of building pales in comparison to the operational costs over it's lifetime. Poor people deserve to live in energy efficient homes with good air quality as much as a rich person. Maybe the idea of trading credits, as mentioned by Jack Ellis above, could somehow even out this imbalance.
Hmmmm... Ok, I see the point. I live in a forest area and I have to say, I don't as much see the size of the houses being built being a problem as much as them being built AT ALL. There are over 1000 houses for sale where I live, and they are STILL BUILDING more! You'd think these contractors would figure out that all they are doing here is driving the prices down and ruining our forest and wildlife. A real shame. It's like this in a lot of areas, and it needs to be slowed or stopped.
Regarding large houses... I happen to live in one, and guess what: my energy consumption is far less than most smaller houses. Why? Because large houses stay cooler in the summer, (especially those with vaulted ceilings) and warmer in winter! maybe my house is just a 'freak', but I'm telling the absolute truth. I personally know of MANY tiny homes and cabins that suck way more energy than mine does. I'm very conscious of energy conservation... my house was built with double-pane glass, etc etc. Heck, I don't even use air-conditioning... I use ceiling fans. So before everyone gets all crazy about this, let's check our facts...
Here's another suggestion: How about also instituting more and better policies to encourage people to rehabilitate existing houses? This is especially relevant in older cities like mine that are experiencing Sprawl Without Growth (SWOG) - they are expanding geographically while populations are flat or declining, meaning that inevitably lots of existing houses are being vacated.
Not all older buildings can be saved, of course, but from an environmental perspective wouldn't it be great to reuse as many of these as possible, bringing people back to neighborhoods with existing infrastructure, short commutes, etc.? After all, "the greenest building is the one that already exists." Rather than continue to subsidize environmentally destructive sprawl, our communities should be focusing on reusing what already exists.
I have a large house with vaulted ceilings, and it sucks energy like mad, and is impossible to cool. We have a swamp cooler (house built in early '80's) and it's hot in summer and cold in winter. And couldn't we put metallic reflector stuff on the roof (where the solar panels aren't placed) like those windshield reflectors--too keep the houses cooler in summer without using so much electricity?