By Scott Kriner, Green Metal Consulting
The Resiliency of buildings and communities remains very important to a variety of organizations, including the Federal government, National Institute of Building Science, National Institute of Standards and Technology, ASHRAE 189.1, Department of Homeland Security, and the Rockefeller Foundation. The dialogue related to resilience is often linked to global climate change and its effect on more powerful storms and a higher incidence of those storms, making our cities, communities and buildings more susceptible to damage. As this article is being written the blizzard of 2016 is now behind us, but the “polar vortex” is heading to the Mid-Atlantic region and causing temperatures to plummet to sub-zero temperatures. Winter is a difficult time to be talking about climate change and global warming, especially in light of record amounts of snow and record cold temperatures. But while we dig out in the east, others are dealing with February tornadoes.
According to the NOAA National Climate Data Center the December 2014 average combined global land and ocean surface temperature was the highest in the 135-year period of recording. Regarding globally-averaged land surface temperatures, warmer-than-average temperatures were observed across nearly all of North and South America, Europe, Africa and Australia. The highest temperature anomalies were observed in parts of Alaska and Siberia.
Are these warming trends responsible for the change in the ocean levels, or the increasing intensity and strange timing of hurricanes, or tornadoes, flooding, and other calamities? That debate is for another day.
One thing is certain though, and that is that we need to re-think how to design, construct and operate buildings in a way to allow them to function before, during and immediately after natural or man-made disasters. The goal is to have occupants surviving the initial impact and returning to normal operations as quickly as possible. The design of resilient buildings includes the specifying of materials that must be resistant to high winds, water pressure, and corrosion. Buildings must also be capable of uninterrupted power generation, maintaining a supply of food and drinking water, and maintaining sanitary functions.
In the resiliency realm, metal building envelope enclosures, steel framing, and structural steel have attractive properties that designers should be aware of. The organizations that are studying how to improve resilient building design need to understand that metal components have a wide variety of qualities that speak to strength, ductility, impact resistance, non- combustibility, corrosion resistance and resistance to water damage. This pedigree of a building material should make metal components attractive to designers, specifiers, and regulators of material used in resilient buildings.
At the larger level, community planners and designers must also re-think how to protect our cities from the damage that can occur from intense storms or from man-made disasters.
This concept is now working its way into the sustainability discussions. In fact the USGBC announced three new Pilot Credits for their LEED program that relate to provisions for resilient design for buildings. They are:
- Assessment and Planning for Resilience
- Design for Enhanced Resilience
- Passive Survivability and Functionality During Emergencies.
The Blizzard of 2016 that hit the Mid-Atlantic and Northeast several weeks ago gave me pause to consider resiliency while surviving a natural disaster. As the snow accumulated up to 32 inches in depth, my home’s attic trusses started to creak and groan with the weight of the snow. I couldn’t help but to wonder how much of that snow could have been shed from the roof with a metal roof system. With that amount of snow piling up around our heat pump I was wondering if there could be a better way to clean off the fins to allow proper air flow through this heating source. Instead I treaded out through 5-6’ drifts to scrape off the snow myself.
I had gasoline in the garage to fuel the snow blower but if more fuel would be needed, I was relying on the resiliency of the nearest gas station to be able to pump my gasoline and for those who were relying on gas-powered generators. Now when I hear commercials for solar powered generators I think twice about that notion. I was also reminded to fill some gallon jugs with water and let them freeze outside. That frozen ice can then be placed in the refrigerator to keep food cold and to avoid spoilage during a possible lengthy power outage.
We had a refrigerator and freezer filled with food, but I felt vulnerable to power outages which could have wiped out our food and water supply. To prepare for a possible power outage, we also filled the bathtub with water to use for flushing toilets if it turned out to be an extended outage.
For additional heat, if necessary, we moved lots of firewood to the back porch for burning in our fireplace. Fortunately that wood was accessible on the front porch.
The preparations for that storm, which turned out to be more intense than predicted, made us think about the resiliency of our home. But resiliency also pertains to hospitals, nursing homes, schools, and other larger buildings that need to have these types of plans in place to prepare for the worst.
Along with the proper planning and designing that can be part of a resilient strategy, the types of materials we use to build our structures can contribute to resiliency. A good example is a new concrete mix that can melt snow as it contacts the surface. Research at the University of Nebraska has proved the performance of conductive concrete that melts snow.
The concrete material uses up to 20% of steel shavings and carbon particles in the mixture. When solidified this concrete can conduct electricity and become warm, thereby melting snow that falls on its surface. Currently the US Federal Aviation Authority is testing the material at airports. The hope is that this type of material could help to reduce flight delays in the winter months. Obviously there is potential for this type of material to be used in driveways, parking lots and roadways as well.
There is other ongoing research dealing with new materials that will be more resilient in their applications on buildings.
Looking into the future, we may be able to better withstand and bounce back from serious natural and man-made disasters that take place in our communities and within the built environment. This may also mean that the grocery stores will stock up on milk, eggs and bread at the very whisper of a predicted snow storm!