Determining adequate water supplies for fire fighting is essential prior to approval of projects. Under the National Building Code (NBC), all Part 3 buildings require separate verifications done for required fire flows. Part 9 buildings are addressed during subdivision planning. In Canada, municipalities rely predominantly upon the Fire Underwriters Survey (FUS) calculations for determining the needed flows for new subdivisions. The FUS methodology considers the class of construction, building height and separations, number of exposures, etc. A typical stick-frame development with homes separated by less than three metres may require fire flows of up to 15,000 litres per minute.
The size of water mains needed for fire flows is greater than what is needed for daily domestic demand. This results in several challenges. These larger water mains result in lower flow rates through the water system, leading to concerns about water aging. Water must either be chemically treated or continually flow to waste to ensure it does not become contaminated. Fire booster pumps may be needed to meet pressure requirements in outlying areas. As municipalities expand, these problems become greater and may result in more operating costs.
Infill construction similarly may require upgrades to municipal water systems. Existing municipal water systems may not be able to meet the fire demand rates; this can limit the ability to develop areas to their full potential.
Home fire sprinklers can offer a solution. Under FUS guidelines, fire flows can be reduced by as much at 30 to 50 per cent when all properties are protected with fire sprinklers. Fire flows can be closer to domestic demand. Water aging becomes less of a problem. Upgrade of pumping systems may not be required. Upgrading existing infrastructure may be avoided. The savings can offset the cost of installing fire sprinklers in the homes. Residents and firefighters benefit from these lifesaving systems, developers can build these needed homes, and municipalities save in the long run on water treatment and distribution costs. Sounds like a win-win-win proposition.