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Even if a small house has lower levels of insulation than a larger house, it's likely to cost less to heat. 1. R-19 walls, R-30 ceilings, double-low-e (U=0.36) vinyl windows, R-4.4 doors, infiltration of .50 ACH, and R-6 ducts in attic; 2. R-13 walls, R-19 attic, insulated glass vinyl windows, R-2.1 doors, infiltration of .50 ACH, and uninsulated ducts; 3. Natural gas at $0.50 per therm; 4. Electricity at $0.10 per kWh.

Having written about green building for more than twenty years now, I've encountered lots of misperceptions. One of those is that green building always has to cost a lot more than conventional building. There are plenty of examples where it does cost more (sometimes significantly more), but it doesn't have to, and green choices can even reduce costs in some cases. Let me explain. When someone is considering building a green home, my first, number-one recommendation is to keep the size down. Since 1950, the average house size in the U.S. has more than doubled, while family size has dropped by 25% -- so we're providing 2.8 times more area per person than we were back then. If you think you need a 3,000 square-foot house, consider whether 2,500 would suffice, or even less. There are some really great homes being built at 1,400 to 1,500 square feet -- homes where every square foot is optimally used and there aren't rooms, like formal dining rooms, that sit empty most of the time.

Often, because we're conditioned to think that bigger is better or because we're told by a real estate agent that a house has to be large to keep its value, we build the largest home possible. By stretching budgets to maximize square footage, we're then often forced to skimp on quality and performance. If, instead, we downsize the house, we can improve its quality (durability, detailing, energy efficiency, green features), and we might even be able to reduce the overall costs.

With green building, there may be some other ways to lower costs that don't require reducing the house size. At the development scale, if we design an onsite infiltration system for stormwater (rather than building a stormwater retention pond or installing storm sewers) that could both reduce costs and make the project greener. With larger facilities, it's sometimes possible to save millions of dollars with such changes -- paying for all of the additional green features.

Where we build can also influence cost. By clustering houses in a development, we can reduce the total amount of pavement, the length of utility lines, and other associated infrastructure costs. By putting a house fairly close to the access road, we both save costs and reduce the impacts of that additional pavement and material usage.

Relative to materials, there are some important ways to use materials more efficiently and save money. With "advanced framing," studs and rafters (or roof trusses) can be installed 24 inches on-center, rather than the standard 16 inches, reducing the amount of wood used in construction. By carefully planning overall building dimensions and ceiling heights, one can optimize material use and reduce cut-off waste.

And it's sometimes possible to have a structural material serve as a finished surface, obviating the need for an additional layer. This can be done when structural floor slabs are made into finished floors (often by pigmenting and/or polishing the concrete), or when a masonry block is used that has a decorative face, eliminating the need for another wall finish.

When it comes to energy, building a green, energy-efficient house usually does increase costs. But we can significantly reduce that extra cost -- occasionally even eliminate it -- by practicing "integrated energy design." If we spend more money on the building envelope (more insulation, tighter construction detailing, and better windows) so that we dramatically reduce the heating and cooling loads, we can often save money on the heating and cooling equipment. With a really tight, energy-efficient house, for example, we might be able to eliminate the $10,000 to $15,000 distributed heating system in favor of one or two simple, through-the-wall-vented, high-efficiency gas space heaters, or even a few strips of electric resistance heat.

If, along with that really well-insulated envelope, we carefully select east- and west-facing window glazings that block most of the solar gain and provide natural shading from appropriately planted trees, we might even be able to eliminate central air conditioning.

These savings on mechanical equipment can cover a lot of the added cost of the improved building envelope. In rare cases, these savings in heating and cooling equipment (if we eliminate a really expensive system, such as a ground-source heat pump, for example), we can pay for all of the envelope improvements and even reduce the total project cost.

I invite you to share your comments on this blog.

To keep up with my latest articles and musings, you can sign up for my Twitter feeds

The table at the beginning, by the way, is from an old Environmental Building News article that still has some interesting takeaways: Small is Beautiful: House Size, Resource Use, and the Environment.

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1 It is good to see that non ch posted by Rodrigo Romo on 08/05/2008 at 07:23 am

It is good to see that non chemical water treatment systems are gaining recognition in these days. I would like to invite you to visit the following website: for a look to another non chemical water treatment technology. Sincerely


2 Mr. Piepkorn, I was one of th posted by Michael Mark on 09/04/2008 at 02:28 pm

Mr. Piepkorn, I was one of the founders of Natural Technologies, Inc., actually just saw this post, and would like to provide you and your readership with some general information on the subject of water- specific technologies notwithstanding. I think your comments regarding non-chemical water treatment technologies reflect a general ignorance across all design communities- green or otherwise- regarding the full spectrum of water’s properties, capabilities, and functions. They also are not in keeping with recent published scientific literature on the general topic of water’s structure and functions.

For some very interesting links and information on water that many will find informative and interesting, and that have nothing to do with our product (which I am happy to discuss with anyone interested in so doing), I submit the following:

1) On the notion that the structure of water is just as important as its composition, and containing an excellent refusal to accept “the common error in rejecting new scientific discoveries by using the absence of evidence as evidence for absence”, a paper entitled The Structure of Liquid Water; Novel Insights From Materials Research; Potential Relevance to Homeopathy:

2) Great, great work by biophysicist Dr. Mae-Wan Ho is available here:

I highly recommend her book entitled The Rainbow & the Worm for anyone interested in the physics of living organisms. It contains great information on how living systems continue to dodge steady-state thermodynamic bullets, and discusses water’s unique role in living processes.

Great fact: Energy received from the sun as light is maintained “in circulation” like an energetic currency within the biosphere for an estimated 20-40 years because of the way living systems utilize and transform the energy into a myriad of forms.

Light hits a leaf, is converted into electrons and dragged into chemical processes whereupon it becomes part of the plant itself, and the plant biodegrades and the light is consumed by bacteria, then the bacteria consumed by a worm, consumed by a bird, excreted into the ocean, consumed by algae, consumed by fish, and on and on it goes.

Non-living systems don’t play that game of energy storage and circulation. Rocks absorb sunlight and simply warm up, and dump heat to the environment whenever the environment is cooler than they are. Their energy patterns are based upon their mass and specific heat: not their bio-physico-chemical self-perpetuating patterns…

A house with thermal mass can absorb heat and temper swings in internal temperature. A house with biodiesel can utilize the heat absorbed by living systems (the plants that became biodiesel) at any time, because that energy has been stored in a coherent form (as stable chemistries with a high energy potential waiting to be released).

Water is very much part of this dance, and its properties in relationship to the coherent electromagnetic structures of living systems are important. Coherent energy storage is also not just chemical; in fact with respect to living systems it is quite often electronic.

According to Dr. Ho: “The precise role of organized biological water in transmitting and perhaps amplifying electromagnetic signals has yet to be defined, but a growing number of us suspect that water may be playing the lead role in living processes [27] ( Water's Effortless Action at a Distance , SiS 32).“

3) Lastly, papers such as this surely suggest there is more to water, and water’s role, than is commonly known or taught today.

“Coherent Dynamics in Water as a Possible Explanation of Biological Membranes Formation”. Del Guidice and Preparata, 1994, Journal of Biological Physics.

Fuchs, Elmar C., Woisetschläger, Jakob, Gatterer, Karl, Maier, Eugen, Pecnik, René, Holler, Gert, and Eisenkölbl, Helmut. “The floating water bridge.” J. Phys. D: Appl. Phys. 40 (2007) 6112-6114.

“The scientists explain that the unusual effect of the floating water bridge, as well as the microstructures they observed during the interaction of water with electric fields, could be another piece to the puzzle of the structure of water. The group said that they are currently investigating how highly ordered microstructures may explain the density change in the water bridge, with the results to appear in a future publication.”

I am happy to discuss our product, but the product will never be understood if the broader role of water within the dynamic structure of living processes is not considered.

Best Regards,

Michael Mark

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