How Many Types Of Plumbing Systems?

There are 6 main plumbing system types used in buildings and homes: potable water supply, water heating, sanitary drainage, venting, storm drainage, fuel gas piping.

Potable Water Supply System

A potable water supply system is the pressurized network that delivers drinkable water to fixtures inside a structure. IPC Chapter 6 covers water supply and distribution piping within buildings.
Use pipe materials such as copper water tube ASTM B88, PEX tubing, or CPVC water distribution components ASTM D2846.
Use fittings such as tees, elbows, couplings, unions, shutoff valves, and backflow prevention parts at cross connection risk points.

Water Heating And Hot Water Recirculation System

A water heating system is the hot water production and delivery network tied to water heaters plus hot water distribution. The IPC covers water heater installations and water distribution systems as part of plumbing regulation scope.
Use PEX tubing pressure temperature ratings such as 160 psi at 73°F, 100 psi at 180°F, and 80 psi at 200°F where listed for the product and standard.
Use fittings such as isolation valves, check valves, unions, temperature mixing valves, and expansion control parts to manage temperature and pressure at fixtures.

Sanitary Drainage System

A sanitary drainage system is the gravity piping that removes wastewater from fixtures to a building drain and sewer connection. IPC Chapter 7 regulates sanitary drainage layout and minimum rules.
Use DWV pipe families such as PVC drain, waste, vent pipe and fittings ASTM D2665 or hubless cast iron soil pipe and fittings ASTM A888.
Use fittings such as wyes, long sweep elbows, traps, cleanouts, and no hub couplings where cast iron joins occur.

A Vent System

A vent system is the air piping that protects trap seals and stabilizes air pressure in drainage lines. IPC Chapter 9 regulates vent arrangements and vent pipe sizing.
The IPC intent for vent methods limits trap seal pressure differential to 1 inch of water column 249 Pa in the cited guidance.
Use vent pipe materials compatible with DWV plus fittings such as vent tees, sanitary tees in approved orientations, roof flashings, and vent terminal parts.

Stormwater Drainage System

A stormwater drainage system is the roof and site runoff piping that conveys rainwater to an approved discharge point. IPC Chapter 11 ties storm drainage sizing to a design rainfall event for the geographic area.
Use components such as roof drains, leaders, area drains, subsoil drains where designed, plus piping suited for storm flow conditions.
Use fittings such as cleanouts, strainers, drainage inlets, and transitions where roof drain bodies join vertical conductors.

Fuel Gas Piping System

A fuel gas piping system is the piping from point of delivery to appliance connections for fuel gas service under NFPA 54 scope language.
Use materials allowed by the adopted fuel gas code in the jurisdiction such as steel pipe, listed CSST, or listed plastic pipe for underground exterior segments where permitted by code.
Use fittings such as threaded elbows and tees, appliance shutoff valves, sediment trap parts, and listed transition fittings per listing and code.

What Are The Types Of Plumbing Pipes?

There are 10 pipe material groups that cover the six plumbing system types above, with each group tied to pressure service, DWV gravity service, or fuel gas service.

1. Copper water tube: potable water lines, hot water lines, equipment feeds. ASTM B88 scope covers copper water tube for general plumbing.

2. PEX tubing: potable water distribution, hot water distribution, hydronic loops where listed. Standard ratings commonly cite 160 psi at 73°F, 100 psi at 180°F, 80 psi at 200°F.

3. CPVC: hot and cold water distribution components up to 180°F 82°C per ASTM D2846 scope.

4. PVC DWV: sanitary drainage and vent pipe and fittings per ASTM D2665 scope.

5. PVC pressure pipe: pressurized liquid distribution in listed schedules per ASTM D1785 scope.

6. Cast iron soil pipe: gravity sanitary and storm drain, waste, vent piping applications in hubless form per ASTM A888 scope.

7. ABS DWV: gravity drainage and venting where permitted by local code and product listing.

8. Galvanized steel: legacy water distribution in older stock, now limited by corrosion concerns and code practice in many regions.

9. Stainless steel: niche potable water, corrosive environments, plus certain industrial plumbing runs.

10. Polyethylene family pipe: underground water service lines and underground fuel gas segments where listed and code-permitted under the adopted code basis.

Which Is The Best Plumbing System Type?

The best plumbing system type is a complete set of systems that matches the building services, since potable water, sanitary drainage, venting, and storm drainage each control a different safety and function requirement. The IPC scope covers water distribution, sanitary drainage, storm drainage, and special piping systems as regulated plumbing topics.
Fuel gas piping ranks as “best” only where gas appliances exist, since NFPA 54 scope applies to fuel gas piping from delivery point to appliance connections.

What Are The Types Of Plumbing Fittings?

There are 7 fitting categories used across the six system types, grouped by function and joint method.

• Direction change fittings: 45° elbow, 90° elbow, long sweep elbow for DWV.

• Branch fittings: tee, wye, combo wye plus 45 for drainage branching.

• Straight join fittings: coupling, repair coupling, union.

• Size change fittings: reducer, increaser, bushing.

• Termination fittings: cap, plug, cleanout adapter.

• Transition fittings: male adapter, female adapter, dielectric union, plastic-to-metal transition.

• Control fittings: stop valve, ball valve, check valve, pressure relief discharge fittings tied to equipment.

Which Plumbing System Type Use In Buildings And Homes?

Most homes and buildings use water supply, water heating, sanitary drainage, venting, and storm drainage. Fuel gas piping appears only in properties with gas service and gas appliances.