Tag Archives: environment

How We Can Redesign Cities to Fight Epidemics

A heat map analyzing the ventilation between urban buildings.

Architecture can be the Secret Weapon To Combat Infectious Diseases
Throughout history, disease outbreaks have forced new innovations in urban design. Fighting cholera epidemics in the 1800s, for example, necessitated the building of new plumbing and sewer systems and the devising of new zoning laws to prevent overcrowding. As the new coronavirus lays bare the need for broader changes across our economy, such as widespread paid sick leave, it might also influence how cities and buildings are built. Continue reading

Things to Know About Exterior Cement Plaster

Exterior cement plaster (stucco) is an exterior finish consisting of portland cement, sand, mixed with water to form a workable plaster. Admixtures may be added to for various purposes including workability. It’s advantages include utility, relatively low first cost, and minimum need for maintenance. Plaster can be a desirable facing material: hard, strong, fire-resistant.
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Solar Incentives in California

Solar panels on  house

Solar Rebates and Tax Credits
California is far and away the most mature residential solar market in the country, which can be both a blessing and a curse in some ways. Overall, it is definitely a net positive for homeowners who live here because they are usually more informed about the intricacies of solar and the state’s solar lobby is powerful enough to fight for important savings tool such as net metering.

But the downside of the mature market is that, unlike other states like Massachusetts and South Carolina, where rebates and energy credits are used to incentivize homeowners to consider solar, California has discontinued almost all of its state-specific solar incentives because the industry is strong enough to sustain itself. Continue reading

Understanding the Living Building Challenge and Its “Petals”

The Living Building Challenge (LBC) is a certification program that defines the most advanced measure of sustainability—providing a framework for design, construction and the symbiotic relationship between people and all aspects of the built environment. It is one of most rigorous performance standards in the industry, as it requires net-zero energy, waste and water by every project. Continue reading

Insulation Materials

Insulation materials run the gamut from bulky fiber materials such as fiberglass, rock and slag wool, cellulose, and natural fibers to rigid foam boards. Bulky materials resist conductive heat flow in a building cavity. Rigid foam boards trap air or another gas to resist conductive heat flow. Other less common materials included cementitious and phenolic foams, vermiculite, and perlite. Continue reading

Selecting Low-Emitting Materials

What are Low-emitting Materials?
Low-emitting materials are products that do not release significant pollutants into the indoor environment. Volatile organic compounds (VOCs) are chemicals found in many common products and building materials that can escape into the air and cause illness and allergic reactions. These emissions are one of the contributors to the situation known as “sick building syndrome” (SBS) in which building occupants experience health and comfort effects. Continue reading

Building Ecology and Indoor Air Quality (IAQ)

Home+Ecology+Stock+ImageIt’s commonly assumed that buildings are simple, inanimate entities, relatively stable over time. This implies that there is little interaction between a building, what’s in it (occupants and contents), and what’s around it (the larger environment). We commonly see the overwhelming majority of the mass of material in a building as relatively unchanged physical material over time. In fact, the true nature of buildings can be viewed as the result of a complex set of dynamic interactions among their physical, chemical, and biological dimensions. Buildings are best described and understood as complex systems.

Research applying the approaches ecologists use to the understanding of ecosystems can help increase our understanding. “Building ecology “ has been proposed as the application of those approaches to the built environment considering the dynamic system of buildings, their occupants, and the larger environment.

Buildings constantly evolve as a result of the changes in the environment around them as well as the occupants, materials, and activities within them. The various surfaces and the air inside a building are constantly interacting, and this interaction results in changes in each. For example, we may see a window as changing slightly over time as it becomes dirty, then is cleaned, accumulates dirt again, is cleaned again, and so on through its life. In fact, the “dirt” we see may be evolving as a result of the interactions among the moisture, chemicals, and biological materials found there.

Humans are covered with bacteria on all surfaces exposed to the environment around us – our skin, respiratory, and digestive tracks. Roughly 2,000 organisms occupy each square centimeter of these surfaces (roughly 15,000 organisms per square inch). We shed our outer skin layer each two weeks. The skin cells and the oils and other chemical in and on them as well the bacteria hitch-hiking a ride on them end up on the floor, furniture, and even the walls and windows.

When bacteria undergo the transformation from a nomadic life (in air) and become sedentary (settle on surfaces), “they undergo a reversible lifestyle switch.” They “…lose motility and become enclosed in a gooey extracellular matrix,” a kind of film on the surface.  There they “sense” their neighbors in the “society” where they find themselves and develop specialized strains to take on different tasks in the community where they find themselves. These evolved bacteria secrete chemicals as part of the “community”.

Of course these chemicals are not occurring independent of the conditions surrounding them, the moisture, chemicals, and particles that are also on the surface or in the air immediately adjacent to it.

This type of diverse coating is present on virtually all indoor surfaces, and the particles, chemicals, and microbes that comprise it are in a sense, each a dynamic ecosystem. While the window glass itself may remain largely unchanged by the processes on its surface, many other surfaces are not as stable. Flooring materials or floor coverings become worn over time, and this wear depends on their material composition, the use that is made of them as well as the maintenance they are given. The wear may result in release of chemicals and particles into the air, and some of these may end up on other surfaces such as the window.

While most of these processes may occur rather slowly, there are some processes that occur much more rapidly, especially those associated with human activities or ventilation with air from outdoors. Chemical interactions produce new chemicals, and moisture on many surfaces support the life, reproduction and evolution of microorganisms. The microorganisms themselves produce chemicals, some of which can alter the pH of the surface and subsequent surface chemistry.

Buildings are designed or intended to respond actively to some of these changes in and around them with heating, cooling, ventilating, air cleaning or illuminating systems. We clean, sanitize, and maintain surfaces to enhance their appearance, performance, or longevity.  In other cases, such changes subtly or even dramatically alter buildings in ways that may be important to their own integrity or their impact on building occupants through the evolution of the physical, chemical, and biological processes that define them at any time. We may find it useful to combine the tools of the physical sciences with those of the biological sciences and, especially, some of the approaches used by scientists studying ecosystems, in order to gain an enhanced understanding of the environments in which we spend the majority of our time, our buildings.

Building ecology was first described by research architect Hal Levin in an article in the April 1981 issue of Progressive Architecture magazine. A full discussion of building ecology and extensive resources can be found at the Building Ecology website, buildingecology.com.