GREEN BUILDING
MAKES GOOD "CENTS"
GREEN BUILDING
MAKES GOOD "CENTS"
Philosophically, the Green Building movement exists in order to address a wide range of environmental problems, from protecting forests and habitats to saving energy, reducing toxics, and keeping materials out of the landfill. It seeks to protect the whole planet as well as a building’s occupants. The buildings created through pursuing these ideals are often healthier to live in, have lower operational and maintenance costs, and a have better “feel” to them. As a result, they achieve a broad appeal far beyond traditional environmentalism.
Defining Green Building is difficult because it encompasses so many environmental issues. Many people turn to checklists of Green products and features, such as Energy-Star appliance ratings, for guidance. While those are very helpful, underlying those lists is a fundamentally different way of thinking. It’s about optimizing a building’s relationship with its external environment. It’s about making buildings reflect the way we use them, not just about how many bedrooms, bathrooms and square feet there are. It’s about knowing what makes people feel good. To use a catch-phrase, Green Building is about building smarter.
Dispelling the Myths of the Green Home
Green homes look weird. The earliest Green homes were research projects focused on a single system (such as solar power). And many of them did look weird. But today’s Green homes offer a wide variety of features integrated into an aesthetically pleasing package.
Green homes require sacrifice. This can be true if you go to extremes and plan to generate your own power and compost all of your garbage. But the typical Green home operates no differently than any other home: it’s just built better and designed to be healthier and more efficient.
Green homes cost more. Up-front construction costs can be higher. However, if you factor in maintenance and operation costs, Green homes often cost less over time. Some banks recognize this and will lend you more money for a Green home, knowing your post-construction obligations such as heating costs will be lessened. And remember: It’s always cheaper to think smarter!
Thinking Green.
Recognize that a home is part of its environment, and therefore should be designed for it. How much solar gain does it have? Does it need to be protected from winds or noise? What about privacy? Recognize that a single person, a family, or a couple with no children all have different requirements, but avoid making a house so specialized that it will not appeal to a future buyer. Recognize that, in addition to the first cost of a home, operations and maintenance over the lifetime of a home are very significant costs. Rather than “keeping up with the Joneses,” owners of Green homes get comfort, health, true quality and lower costs because their homes make sense instead of being big.
Is it Green or Greenwashing?
Once you understand the principles, you can look at a home and ask if it follows them. Ask simple questions: What quality are the materials and workmanship? Are the spaces inviting? Is the house comfortable? Green homes come in a wide range, from those with just a handful of simple features to those with many features and potentially significant up-front cost. “Greenwashing” refers to an unsystematic addition of green features without regard to the underlying environmental concerns.
Selecting materials and systems.
Although much published information on Green building focuses on a checklist of Green materials and systems, what matters most is in how they are used. The old adage “Reduce, Reuse, Recycle” is just as true in home building as anywhere else: the less you use, the lower the impact (and cost!). Re-using existing materials can be difficult, but can also be cost-effective. Finally, using products that are recycled, recyclable, or sustainably harvested lowers the overall impact on the environment. Many manufactures are now producing “Green” products, and many of them are in fact “Green,” but those of dubious merit also exist. All products have some environmental impact. Independent advice is the most reliable information.
Thinking Green: An Example
People often equate energy efficiency with added insulation and high efficiency furnaces, but when we look at the big picture, other options appear. So we start with the principle: a building’s energy use is affected by its quantity of heat input and heat loss.
Now, we step back and remind ourselves that our goal is not just reducing our bills, but providing for our comfort, and so we ask what contributes to comfort? Comfort is due to the temperature we perceive, not what we measure, and that perception is due to:
1. The actual air temperature
2. The radiant temperature of all the room’s surfaces: Warm surfaces radiate heat to us and cold ones take it from us.
3. Amount of air movement: room temperature air movement produces a cooling effect.
Heating the air alone can make us comfortable. Alternatively we can increase the temperature of the wall, floor and ceiling, decrease the air temperature, and still perceive the same comfort (uninsulated walls can be under 60 degrees!). To accomplish this, we insulate just enough so that the surface temperature will stay near room temperature.
Now lets look at the sources of heat gain:
1. Furnace, boiler or heat pump (i.e. something that uses energy).
2. Solar gain (Even a Seattle home can supply up to 60% of its heat via solar).
3. Waste heat from appliances.
And then of loss:
1. Through walls, ceiling & floor.
2. Through the windows.
3. Via air leakage (including opening doors).
4. Via the ventilation system.
Calculations show that by orienting our windows to the south, we can use solar gain to reduce our energy consumption in the spring & fall. Additionally, when we add up the wasted heat from our appliances, it can be a significant part of our heat in a moderately sized, well insulated home! (Although we must rid of this heat in the summer, it is easily accomplished in our cool climate.) The heat loss of a building is mostly due to air leakage, followed closely by loss through the windows. So before adding excess insulation, we improve those areas first.
While this is an incomplete analysis, it shows that by looking at the bigger picture, we can put our money where it counts most!
Tradeoffs & Synergies.
Savings in one place can lead to savings somewhere else. By using some solar gain, adding a little extra insulation and keeping our house size moderate, we can significantly reduce the size of our heater. An efficient clothes washer not only saves water, but makes our clothes last longer. By keeping our hot water pipe short, we not only avoid wasting hot water, we get quick delivery!
We also often run into difficult tradeoffs. For example providing fresh air is a source of heat loss (which can then be mitigated somewhat by installing a heat-recovery ventilation device). Another common tradeoff in our area is taking advantage of views (which are often east/west) versus solar gain (which is achieved by facing south). We also find recycled products that aren’t recyclable, or that have dubious toxicity. Many tradeoffs are easy to make, while others than can be difficult and can only be guided by personal philosophy.
Know what's important to you.
When it comes to making trade-offs, you will need to decide your philosophy up-front. How much extra are you willing to spend, if any? Green building encompasses energy efficiency, water and materials efficiency, human health, and site protection and restoration. Which of these issues is the leading priority for you? We can engineer an incredibly efficient home, but if we sacrifice aesthetics and comfort, the home becomes uninviting. While ideally we’d like to be as Green as possible, in reality we each decide how far we want to go, and that in turn is determined in part by whether you’re doing a small remodel, a large remodel, or new construction. By simply replacing an inefficient washer with a new Energy-Star model, you’ve taken a step in the right direction!
Written by: Bob Scheulen
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