Plumbing Design

Types of Piping

Water Supply and Return Used for both cold and hot water distribution.

Materials: copper, PEX (cross-linked polyethylene), and CPVC (chlorinated polyvinyl chloride). In residential settings, copper piping is commonly used in mechanical rooms, while PEX is favored for other areas. In light commercial applications, copper piping is typically preferred.

Pipe Joining: ProPress fittings are more expensive than soldering or brazing, but are often preferred for their ease of installation. These fittings utilize a mechanical press to join copper pipes together. Embedded within each fitting is an EPDM (Ethylene Propylene Diene Monomer) O-ring, ensuring a tight seal between the pipe and the fitting.


Wastewater Efficient sewage and blackwater disposal are vital for maintaining a hygienic and safe environment and are integral parts of the drain-waste-vent (DWV) system.

Materials: PVC, ABS, or cast iron. ABS is often preferred due to its affordability and durability. Cast iron, is often used in light commercial due to its strength, however it costs more and is susceptible to corrosion.

Pipe Slope: The minimum slope for pipes with internal diameters of 2-½ to 4 inches is 1/4 inch per foot (2% slope), while for pipes with internal diameters of 6 to 15 inches, it is 1/8 inch per foot (1% slope).


Fire Protection Wet and dry sprinkler systems play a crucial role in addressing fire emergencies. 

Wet sprinklers: remain constantly filled with water, ensuring immediate response to a fire incident.

Dry sprinklers: remain charged with pressurized air or nitrogen until activated, preventing water flow until necessary. When a dry sprinkler head is activated, the air pressure drops, allowing a valve to open and water to flow into the pipes and out of the activated sprinkler head. Dry systems are typically used in areas where freezing temperatures are a concern such as unheated spaces.

Fuel Gas

Routine maintenance and inspection further guarantee system integrity, preempting potential leaks or corrosion threats. Adequate ventilation and clearances are also vital for mitigating fire risks.

Materials: stainless steel or corrosion-resistant alloys.

Pipe Joining: Soldering or brazing is commonly preferred. ProPress fittings are typically not recommended or approved for use because fuel gas piping requires exceptionally secure and reliable connections to prevent leaks and ensure safety.


Stormwater Efficient sewer management is crucial for preventing flooding and erosion.

Options: bioswales, rain gardens, detention basins, green roofs, living walls, stormwater harvesting, swales, channels, and hydrodynamic separators.

Materials: permeable concrete, corrugated metal, and high-density polyethylene.