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Clearing up the confusion about ‘sustainable’ building

Thatch roofs offer the virtues of high insulating value, low embodied energy and low environmental impacts, but practical issues of code compliance, fire hazard and labor-intensive prep work discourage their use in North America.
Thatch roofs offer the virtues of high insulating value, low embodied energy and low environmental impacts, but practical issues of code compliance, fire hazard and labor-intensive prep work discourage their use in North America. Chris Magwood

Nearly every serious profession has its expert practitioners and its big-picture thinkers, and many of those individuals tend to end up solidly in one camp or the other. The practitioners are hands-on types, tackling the whats and hows, sorting out the everyday tasks and immediate issues, while the theorists ponder the whys and wherefores and often leave a broader, if less direct, mark on the discipline’s landscape.

Chris Magwood — builder, author and teacher — seems to have figured out how to do both. He has a practical knowledge of building techniques and materials, both conventional and “alternative,” but he also brings a historical sense of the craft with him, describing the past that shaped our building habits during the last century, and venturing some thoughts on where we might be headed in this new one. He offers both in a new book, Making Better Buildings: A Comparative Guide to Sustainable Construction.

The Industrial Revolution, Magwood explains, gradually displaced centuries-old building technologies (centered on wood, stone and brick) and ushered in an age of steel, concrete and glass. Along the way, mechanization changed almost every part of the process, from resource extraction and raw materials processing to manufacturing, fabrication and installation methods. It brought speed, uniformity and efficiency, but at a high cost to the environment and with an unprecedented appetite for cheap energy provided by coal and petroleum.

Now environmental issues, the specter of worsening climate extremes and the end of cheap fossil fuels are forcing us to rethink the kind of buildings we make and how we make them. This shift, Magwood believes, will be as fundamental and far-reaching as the changes of a century ago. It will involve more new and alternative materials and techniques and require a willingness to depart from some old or established habits.

It’s this need to change that brings Magwood back to the issue of everyday (micro) choices versus the big-picture (macro) choices of how and what we build. We humans, he says, have a habit of resisting change by sticking stubbornly to what we know and being overly critical of what’s new. Our inherent bias toward the status quo as “normal” makes us blind to flaws in familiar things and reluctant to embrace alternatives.

His first example? Wood. It’s far from a perfect material, he says; it burns, twists and cracks, supports mold growth, succumbs to rot and insects, varies widely in strength and dimensional stability, and often requires long-distance transport to end-users.

Despite these “micro-flaws,” however, wood comes from abundant renewable resources (trees) and is affordable, easily worked and versatile, as either sawn lumber or engineered products, such as plywood or laminated-veneer beams. As such, it’s widely used as a building material across the entire planet.

Paradoxically, any newly introduced material with wood’s drawbacks would likely never gain such widespread acceptance.

Magwood pushes the point further with his second example: the flush toilet. Most of us have experienced a toilet backup, but we accept that occasional problem as a worthwhile trade-off for the convenience and wouldn’t think of discarding the technology outright.

On the other hand, Magwood sometimes hears comments that composting toilets “don’t work,” often a secondhand report about a single incident of odor or incomplete composting. In truth, he says, both technologies have particular “micro-flaws,” but the “macro” picture is much more significant.

On this big-picture level, flush-toilet technology involves using vast amounts of valuable potable water, an expensive public infrastructure to treat that water and the transfer of sometimes untreated sewage into rivers, lakes and oceans. Conversely, composting toilets use little or no water, turn our bio-waste into usable fertilizer and require no public infrastructure.

This larger context, and not merely the everyday incidental stuff, is what Magwood says should be driving our building decisions.

To that end, he devotes the bulk of the book to evaluating 12 different categories of building systems (materials and methods combined) for their overall value and sustainability. This includes foundations, wall and roof structures, sheathing and siding, insulation, windows, heating and cooling systems, water systems and others. Each category/method is graded according to criteria that include the environmental impacts of harvesting/producing/transporting the material, its embodied energy (how much energy it takes to produce/transport), waste factors, energy efficiency, purchase costs, labor requirements, durability, code compliance, indoor air quality and other factors.

The book manages to achieve a rare combination of detail and clarity that makes it useful for professional designers/builders while still being accessible to homeowners who want to understand more options for their project.

There is really no agenda here except to show how these building systems compare using a consistent set of benchmarks, to take the mystique and confusion out of some unfamiliar choices and to clarify the definition of “sustainable” by showing the often hidden consequences of our building choices.

Book Information

“Making Better Buildings” by Chris Magwood; 2014; $39.95; softcover, 440 pages; New Society Publishers; 800-567-6772; www.newsociety.com