Resilient Buildings: Plumbing & Fire Protection Design Considerations
Building design for the future may take into consideration several items regarding plumbing that are obvious to some such as contactless fixtures and an increase in availability of hand washing sinks. But some other best practices in plumbing design and maintenance will become more prevalent in our design process as well. Below are some observations and considerations for facilities owners as they look at building, maintaining, and upgrading facilities' plumbing:
In real estate it is about location; it is the same for plumbing. The equipment location in a building can increase proper maintenance and easily maintained equipment is safer for the occupants. The location of plumbing equipment begins with the overall design of the building and making plumbing accessible may not always seem like a priority for designers. But plumbing water systems are under pressure and can do a lot of damage to the entire space if neglected. Water heaters for instance require access to the water heater relief valves (temperature and/or pressure) valve. Failed valves have exploded like a missile. Locating equipment so that the valve outlet is easily visible will allow any water to be observed and prevent hazardous water heater failures.
There are two routes for rainwater to exit the roof. A typical drain removes the rain water and second path is a backup drain, in case the first one gets blocked up with debris and stops working. There is more than one way to have a secondary drainage path. It could be another roof drain, or it could be a scupper or gutters can act as the primary and secondary path. The accumulation of water on the roof should a high priority because if the structure is not designed for it, then a roof collapse is possible.
Emergency fixtures including eyewash and showers should always be available if chemicals are used on site in laboratories and industrial spaces. The latest standard ANSI/ISEA Z358.1-2014 gives guidance for the location of the emergency fixtures and the flow rates and temperature of water required. It's important to make sure emergency fixtures are working and maintained for safe use as they are infrequently used and not often top of mind for occupants.
Bacteria / Infection Control
Legionella is a bacteria that if exposed with a compromised immune system can cause lung conditions like pneumonia and sometimes death. The risk is generally low for most people but the bacteria can thrive in warm water conditions like a water heater, a cooling tower, or a fountain inside a building. The bacteria thrives in water temperatures between 68 F and 122 F. So the general rule for a water heater is to keep the water temperature setting at 140 F to be affective against the bacteria. That solves part of the problem, the next part is to considering 140 F water at a hand washing lavatory and scalding the user. That is why tempering valves are designed for each sink to ensure a lower temperature water exits from the sink or lavatory where scalding can occur.
Another concern with infection control, is the potential increased risk from stagnant water in pipes that may result from building closure during shut down. The American Industrial Hygiene Association (AIHA) notes in its guidance that there is a risk of getting the water-borne Legionnaires’ disease after re-opening a building even after only one week of closure. Since many large building have been closed for several weeks, it is important that owners, safely flush water pipes prior to occupancy.
The standard of how to sprinkler a building is within NFPA 13. A similar standards exists for residential type of structures 13R and 13D. The NFPA 13 standard is an installation standard and does not specify which buildings or structures require a sprinkler system. The guidance of when to sprinkler a building resides with local building code; local fire authority, NFPA 101, Life Safety Code; or insurance requirements. Deciding to voluntarily sprinkler a building even though it is not required can have property benefits and save lives. A Tec Inc. engineer can assist with deciding to sprinkler your project.
John Milenius, PE, LEED AP
Recognized as a pragmatic and skilled expert in HVAC engineering and plumbing design, John focuses on making the most of project budgets and schedules for our clients. A skilled troubleshooter and proponent of increasing energy efficiency, John manages and leads or mechanical engineering staff at Tec. In addition, he is always looking to help future AEC professionals along the way.
Steve Schwarten, CSI, CDT
Steve has 30 years of experience in mechanical and plumbing design. During his tenure he's gained experience in every building type and has worked on some of Tec's most complex infrastructure projects. He's always willing to offer his guidance to younger professionals and is known for assisting the team in meeting tight deadlines.