Fire can severely damage a building while threatening human life, so it should come as no surprise that the NYC Department of Buildings places strict requirements for fire protection systems. These systems must meet various codes to be approved for use in New York City.
NYC Fire Code
NYC Building Code, where Chapters 7 & 9 and Appendix Q deal exclusively with the topic
NFPA 13, 13D, 13R, 14, 20 and 72, as modified by Appendix Q of the Building Code
With so many requirements to meet fire protection systems can be expensive, but it is possible to minimize their cost with smart decisions during the design process. The two main areas of opportunity for reducing the cost of fire protection systems are adequate standpipe selection, and optimization of architectural features to minimize the number of sprinkler heads.
It is important to note that a series of specific requirements must be met for automatic sprinklers to be mandatory, and they are covered in depth in Chapter 9, Section BC 903. There are many cases where occupancies fall under the categories above, but specific requirements are not met, so sprinklers systems are optional.
Where are Automatic Sprinklers Not Required or Not Allowed?
Automatic sprinkler systems are not required in electrical equipment rooms that meet all the following conditions:
Exclusive for dry-type electrical equipment
Separated from the building with a two-hour fire barrier
The room has no fuel storage
The NYC Building Code forbids the use of automatic sprinklers in elevator machine rooms and machinery spaces.
Dual Water Sources
There are some applications where the Building Code requires sprinkler systems to have two independent water sources:
Group A-1, when stages are larger than 1000 square feet or higher than 40 feet
General Requirements for Fire Protection Systems in New York City
If automatic sprinklers are used, the fire protection system must have a central monitoring station. The only exceptions are one- or two-family dwellings, or systems with less than 20 sprinkler heads. When a building is subject to a major renovation, fire protection system compliance may be assessed for the altered areas only or for the entire building, as stated by the following rules:
Fire Protection System Assessment
- Renovation over 60% of building value - Renovation over 50% of building value, if there are four or more dwelling units
Altered areas only
- Renovation between 30 and 60% of building value - Renovation between 30 and 50% of building value, if there are four or more dwelling units - Renovations in R-1 or R-2 occupancies, regardless of building value percentage
Fire Pump Protection Requirements
As implied by their name, fire pumps are used to provide water for fire protection systems. In many cases, fire pumps supply water for an automatic sprinkler system, an automatic standpipe, or a combination of both; if the fire pump is exclusively for sprinklers, it is classified as a sprinkler booster pump.
Given that fire pumps play a critical role when extinguishing fires, measures must be taken to protect the equipment itself. The NYC Building Code (Ch. 9, Section BC 913) requires that fire pumps be installed in dedicated rooms with two-hour fire barriers or horizontal assemblies, except in the following cases:
In buildings that are not high-rise and are equipped with automatic sprinklers, the required fire rating is only one hour.
When the fire pump is physically separated, as indicated by NFPA 20.
When the fire pump is in a mechanical equipment room where two-hour fire barriers or horizontal assemblies are already in place, where a dedicated room would be redundant.
The feeder conductors supplying electric power to a fire pump must be enclosed by two inches of concrete, or by an assembly with a minimum fire rating of two hours.
Standpipe Selection: Types and Effect on System Cost
A standpipe has the purpose of transferring water from a main supply to the hose connections distributed throughout a building. Most of them can be classified as automatic or manual systems, and each type can be either dry or wet.
Automatic standpipes draw water automatically when a hose valve is opened, as implied by their name, and installing a water supply capable of meeting the full system demand is mandatory. On the other hand, manual standpipes do not have a water supply, and are designed for the connection of a Fire Department pumper.
Wet standpipes are filled with water, while dry standpipes are normally filled with pressurized air.
With these characteristics, there are four possible combinations: automatic dry, automatic wet, manual dry and manual wet standpipes. There is a fifth type of standpipe, semiautomatic dry, which draws water when signaled by a remote-control device.
To reduce system cost, manual standpipes should be used whenever possible, unless the NYC Building Code makes automatic standpipes mandatory for a specific application. Manual standpipes reduce installation cost drastically, since only the sprinkler system demand is considered when sizing the water supply and fire pumps.
Standpipe systems are covered in depth in Chapter 9, Section BC 905 of the NYC Building Code. The following are some examples of applications where automatic wet standpipes are mandatory:
Buildings classified as Group A, without fire sprinklers and with more than 1000 occupants.
Covered mall buildings.
Relationship Between Automatic Sprinkler System Cost and Architectural Design
To meet the NYC Building Code, a sprinkler system must provide full coverage of the building, and if architectural features impede it, the total number of sprinkler heads must be increased as required until full coverage is achieved. When architectural design is carried out before fire protection design, and both teams work in isolation, the automatic sprinkler system normally ends up being much more expensive than necessary.
The total cost of a sprinkler system can be reduced greatly by holding a meeting between the teams in charge of architectural and fire protection design as soon as the project starts. This way, they can work concurrently rather than sequentially, and building architecture can be optimized so that full coverage is achieved with the minimal number of sprinkler heads possible. Using a Building Information Modeling (BIM) tool can also be of great help when optimizing the layout of a sprinkler system.
Fire protection systems are subject to stringent requirements in New York City, so any improvements that reduce their cost are welcome. Automatic standpipes should be avoided unless they are mandatory, since they greatly increase the required capacity of fire pumps and their associated water supplies. In addition, it is possible to reduce the total number of sprinklers by improving coordination and collaboration among the teams responsible for architectural design and fire protection system design and specification.
An engineering professional or design firm can help you optimize fire protection systems, while meeting all requirements set forth in the applicable codes and standards.
At Nearby EngineersNew York Engineers , we search for simple, eloquent solutions to complex problems. We minimize construction costs by eliminating the extraneous and focusing on the overall efficiency for the most streamlined designs.