Breath and Movement in Structure

Stresses - tension, compression, load distribution. HMB

The EPA estimates that Americans spend 90% of their time indoors.[1] What we breathe during this time is approximately 2-5 times more toxic than exterior air quality.[2] How, and why has it gotten to this point? A space which chooses to forego the upfront costs of design and material selection for proper ventilation can result in much greater costs, for the structure and its occupants, down the line. People know to avoid using certain materials that diminish interior air quality, particularly those high in VOC’s (volatile organic compounds - which are gases emitted from certain solids and liquids at room temperature). VOC’s are most commonly found in paints, carpeting, varnishes, formaldehyde (found in pressed wood products, eg plywood, flooring etc), vinyl, and other adhesives. Though to some extent they’re unavoidable based on our established building systems. Is this cultural? Why has the bar been set so low? A shift in priority of considerations, from profit to well-being, from immediacy to longevity, is necessary in improving our health, which starts with the health of our homes. The quality of air we breathe inside these structures, begins with their ability to breathe themselves.  

The primary goal of creating an ‘airtight structure’ is shortsighted in its outlook. Driven by the prospect of lowering the cost of energy bills, it can jeopardize the durability and lifespan of a building, as well as its inhabitants. An airtight building with a mechanical ventilation system, analogous to our lungs, helps to take in fresh air from the exterior, and transfer stale air from the inside back out. These are great, and undoubtedly aid in the structures ability to breathe, but are still a form of mechanized life support – a crutch enabling the structure to do something it wouldn’t be able to do without it. In order to achieve a more natural equilibrium between the quality of air inside and out, the structure must be self-generating in its breath, in sync with the breath of its environment. This can be achieved through proper material selection.

It is critical that the sum of the building’s materials are friendly with each other, familiar with the local climate, and able to work as a team. They must orchestrate the expansion and contraction, or breath, not only in isolation, but in harmony with each other. Using materials that are native to the region not only lowers the embodied carbon of the structure, but helps it to flourish in the local climate. Wood from a tropical rainforest used to clad the exterior of a building in a semi-arid, cool climate, will not know how to act, and will very likely have trouble collaborating with other local species. Instead, a combination of local materials used to comprise the majority of the building envelope will be acclimatized, cohesive, and naturally permeable.

The goal is for the assembly of these pieces to stand as a ‘gestalt’ – an organized whole that is greater than the sum of its parts, mimicking interdependencies in nature.[3] As the inhabitants of a home, we are an integral part of its self-sustaining web. If a building is able to achieve this level of assimilation – it is going with nature rather than against it. It is passively camouflaged in beautiful forms of organic metaphor and pattern – expansion and contraction, coming and going, ceaseless motion, a constant flow of energy. This level of integration facilitates a higher level of air quality and well-being in its occupants.

This level of integration is complex, and begins with the buildings anatomy. The skin of a structure is the mosaic of materials used in its wall systems. It is a layered membrane (in cold climates) of the interior wall, framing, insulation, sheathing, some sort of building wrap, and siding. The frame supports these materials like a skeleton. To accommodate for the skins elasticity, the frame needs ligaments and tendons in order to be somewhat flexible itself. Deadlocked rigidity in the frame, as in many things, is the enemy. Though of course you want it sturdy. A frame built of completely immobile materials, like steel, on top of an ever-shifting earth, is limited in its lifespan and physical intelligence. Its capacity to cope with the fluctuations and movement in the materials it supports, as they are slightly ever-shifting as well, isn’t as good as something more flexible. A frame’s inability to jive with the rhythm of the live elements in its environment, as well as its living skin and active internal occupants, make it predisposed to becoming sick, cracking, splitting, and eventually failing. This is a nice reminder for us to keep moving and stretching! Durability, and an ability to work with the elements, is found in natural, native materials, and can also be accounted for in deliberate design.

Ying County Buddhist Pagoda, built in 1056, Shanxi Province in northern China’s Yellow Plateau. It is the oldest surviving timber frame pagoda in the world. The flexibility in its wooden interlocking joints has helped it survive a dozen major earthquakes over the course of a thousand years, with three measuring more than 6 on the richter scale.

Joint details

Accommodating for spontaneity, ie earthquakes. Resilience embodied.

Similar to our bodies being able to regulate themselves based on changes in the external environment, a properly built structure is equipped to synchronize with the fluctuations of temperature, moisture, and light. Mitigating the differences between climates indoors and outdoors, barring temperature and humidity in most climates, is vital to the health of a structure, its air quality, and its occupants.

In looking at a building that has survived as long as the Ying Pagoda, one can’t help but notice elements of Taoist principles and Chinese culture symbolized in the design of its structure. Can these be attributed to the building’s longevity? Taoism is primarily concerned with the observation of nature, its patterns, and the discovery of its way, or Tao. The sage, much like the pagoda, recognizes these patterns and directs his actions according to them. In this way, the building, or he, becomes ‘one with the Tao,’ living in harmony with nature. The principal characteristic of the Tao is the cyclic nature of ceaseless motion and change – which the pagoda’s design bluntly embodies. Human happiness, according to Taoists, is achieved when one follows the natural order, acting spontaneously and trusting one’s intuitive knowledge.[4] A great deal of trust was imbued unto the structure of the pagoda, as it has proven able to adjust and react in spontaneous harmony with its environment, blending into the regional way, in the very same way a Taoist might.  

A culture of competition for profit, as opposed to collaboration for well-being, largely neglects the goal of a more sustainable, healthier future. Our cultural priorities and primary concerns as Americans are reflected in the buildings we choose to make in interesting ways – their size, function, and environmental presence. The work of implementing fundamental pillars of sustainable ecosystems in our design, architecturally, economically, socially – viewing these things as interdependent, just as the components of a cohesive structure – is key in moving towards a more symbiotic relationship between humans and the environment. The foundation of this work begins with us. In many ways, our success begins in the home, and is predicated upon the quality of nourishment it can give us. After all, that’s where we spend 90% of our lives.

If you are interested in reading more about air in buildings and what factors contribute to its quality, go here: https://9foundations.forhealth.org/

[1] “A Guide to Indoor Air Quality.” EPA, Environmental Protection Agency, https://www.epa.gov/indoor-air-quality-iaq/inside-story-guide-indoor-air-quality. 

[2] Ibid

[3] https://www.merriam-webster.com/dictionary/gestalt

[4] Capra, Fritjof. The Tao of Physics: An Exploration of the Parallels between Modern Physics and Eastern Mysticism. Berkeley, Calif.: Shambhala, 1975. 93