The Rules for Now Have Changed
The Covid 19 Pandemic has changed design. As we proceed down the road with dealing with the pandemic, one of the biggest issues is “Social Distancing”. Dealing with the general rule of six feet of space is our basic guide line. Like any number, it is kind of based on science, but it is an arbitrary number that is agreed upon. This is the same for any numeric value in the building code. Why at 50 occupants are we require to have two means of egresses, but not at 49 occupants?
Using the basic 6-feet of distancing, we’ll use 36 square feet as our basic minimum occupied area for Social Distancing. This should be considered a minimum value. So how does that affect what we have been using and already designed to using the values in the Building Code. Let us take a look at Table 1004.5, which are our basic occupant load factors we currently use to determine our egress elements. Any value that is less than 36 square feet per occupant will need to be adjusted to comply with the current Social Distancing rules. Here are some current occupant load factors that will be affected: Airport Terminals at 20 Square Feet (SF)/occupant, waiting areas at 15 SF/occ, all assembly spaces and education at 20 SF/occ. Some other general rules being applied are no more than 12 for an indoor gathering. These rules vary from county to county as well as country to country.
For small assembly areas, such as conference rooms and dining spaces, the code generally uses 15 SF per occupant. When the number is increased to a minimum 36 SF per occupant for Social Distancing, that is an increase of 140% of footage. For a meeting space of 700 SF, which is permitted by code to have 46 occupants, that is now reduced to 19 occupants or less. That is
about 60% less occupants. For an indoor dining space, 60% less users is significant for a business. Some locations are talking about allow half the normal occupant load. This would be higher that allowed under the Social Distancing guideline numbers would permit. For a group sitting around a table, or even at a bar, Social Distancing rules would be hard to maintain and enforce. Part of the reason of going out is to socialize.
For schools and classroom where the normal occupant load factor is 20 SF/Occupant, going to a min. 36 SF is an increase of 80%. For a 440 SF classroom, the normal maximum occupant load is 22 students. To comply with Social Distancing, the number is reduced to 12 occupants maximum. Most school cannot accommodate a normal class load in the room they have now and would have to reduce class sizes to maintain social distancing. What the approach the schools take will have to be seen.
Since the guidelines for reopening are still in development stages, nothing has been said yet regarding small enclosed spaces, like elevators, lobby security queues and other common use spaces, like restrooms. Are the social distancing rules to be applied here?
There is some lot of talk for other mitigating measures, such as additional ventilations. There are many unanswered questions. Does increased air circulation within an enclosed space increase the chances of spreading the virus? Will additional filtration be required? Will we have to rezone systems to limit the spread? Increasing circulation with additional outside air would have an impact on energy use.
We have a lot of the technology to crated isolation rooms and clean rooms. To include these elements in all buildings would be costly. These types of facilities and uses are usually under the I/Institutional and H/Hazardous use classifications. There are a lot of other elements that go along with these uses like the means of egress are evaluated differently. The concept of zoned exiting for hospitals and jails, would not be easily included in a normal building.
Hopefully, these are temporary measures to get through our current crisis and we can go back to our normal design criteria. Only time will tell. Right now, Social Distancing is the rule.
Kerwin Lee, AIA
Comments by Erick Mikiten, AIA:
These thoughts fit perfectly under the idea of “Resilience”, which has been getting increased attention from architects in the last few years. The National Institute of Building Sciences defines Resilience as “a strategy to enhance the ability of a building, facility, or community to both prevent damage and to
recover from damage.”
From 911 to Hurricane Katrina, to California wildfires, Resilience has focused more on buildings’ resistance to damage or their physical function after damage. With COVID-19, we’re thinking more about the functioning of unchanged buildings for a changed set of users.
How do we plan ahead for an unknown future? The National Institute of Building Sciences’ online Whole Building Design Guide has ideas about passive and active threats to buildings, security concepts, and covers considerations around maintaining building services through various hazard situations.
Sustainable design-oriented architects have expanded these ideas of Resilience, advocating that buildings should be self-sufficient so they can continue operating if they lose power, be able to filter and condition the inside air in the event of wildfire smoke in the air, etc.
I suggest that we expand those ideas one step further, ensuring that our buildings are resilient enough to accommodate the changes of the occupants over time. This means thinking ahead about things like Aging In Place, creating easy and safe ingress and egress regardless of the user’s ability to climb stairs, or
making kitchens that are flexible enough to work well whether someone is 6’-5” or 5’-0” and standing, using a stool, or seated in a wheelchair.
And once we’re thinking in those terms, where we’re putting the user first (which we all learned in freshman year of architecture school), we naturally start thinking about ideas like homes that work well for living or for working (whether during a pandemic or not) or how schools or commercial buildings can adapt to different types of occupancies. Maybe that could lead to new ideas about how schools could be easily reconfigured to be more creatively used during the summer months or how office buildings might be converted to housing in the future.
The great sustainability architect William McDonough, in his Bill of Rights for the Planet in 2000, wrote that we need to “Emphasize the full life-cycle of what we create.” He was referring both to the life cycle of materials we architects specify and to creating buildings that could be re-purposed in the future, like his GAP headquarters in San Bruno.
Similarly, in 1987, the UN’s Bruntland Commission Report said “Sustainable developments meet present needs without compromising the ability of future generations to meet their needs.” This implicitly acknowledges the reality of change, and calls on architects to think flexibly. They recognized this 33 years ago, and this needs to be a touchstone for our work every day.