GA Plumber cheat sheet

The International Plumbing Code (IPC) is the minimum plumbing standard adopted statewide in Georgia; local jurisdictions may amend it to be more restrictive but not less restrictive.

A permit is required before installing, altering, repairing, or replacing any plumbing system; routine maintenance of existing fixtures is generally exempt.

Plumbing work must be performed by a licensed master or journeyman plumber, or by an apprentice under direct supervision of a licensed plumber.

Only a licensed master plumber may contract for plumbing work and pull plumbing permits.

Referenced standards (ASTM, ASME, CSA, NSF, CISPI) are enforceable parts of the code; an unlisted material requires written approval of the authority having jurisdiction (AHJ).

When two code provisions conflict, the more restrictive requirement governs; where the code is silent, the manufacturer's listed installation instructions govern.

The AHJ may order any unsafe, insanitary, or defective plumbing system disconnected and its use prohibited until corrected.

The code governs the erection, installation, alteration, repair, relocation, replacement, addition to, use, and maintenance of plumbing systems.

Scope includes water supply and distribution, fixtures and fittings, sanitary and storm drainage, vents, traps, interceptors, water heaters, and special wastes.

Lawfully installed existing plumbing need not be upgraded unless it is unsafe, insanitary, or ordered corrected by the AHJ.

Alternate materials or methods may be used when the AHJ finds them equivalent in quality, strength, effectiveness, fire resistance, durability, and safety.

A permit application must be accompanied by plans and specifications showing size, location, and type of piping and fixtures; permits expire if work does not commence within the period stated by the jurisdiction.

Rough-in, building sewer, and final inspections must be requested and passed before the work is concealed or placed in service.

A board of appeals hears disputes over code interpretation and decisions of the AHJ.

Cross-connection: any actual or potential connection between the potable water supply and a source of contamination or pollution.

Backflow: the reversal of normal flow of water, liquids, or gases into the potable water system by backsiphonage or backpressure.

Fixture unit (FU): a measure of the probable hydraulic load of a fixture; 1 drainage fixture unit equals 1 cubic foot per minute of flow (about 7.5 gpm).

Developed length: the total length measured along the centerline of pipe and fittings, including valves and fittings converted to equivalent pipe length.

Trap seal: the vertical distance between the crown weir and the top of the dip of the trap, required to be 2 inches minimum and 4 inches maximum.

Air gap: the unobstructed vertical distance through free atmosphere between a water outlet and the flood-level rim of the receptor.

Flood-level rim: the top edge of a receptor from which water would overflow onto the floor.

Stack: a general term for any vertical line of piping; a branch is a horizontal run connecting fixtures to a stack or drain.

Isometric drawings are drawn on three axes: vertical lines are drawn vertical, and the two horizontal axes are drawn at 30 degrees above the horizontal.

Drainage lines are typically shown solid; vents are commonly drawn dashed or distinguished by leader labels such as 'V' or 'VENT'.

Common abbreviations: WC = water closet, LAV = lavatory, KS = kitchen sink, FD = floor drain, CO = cleanout, FCO = floor cleanout, HWR = hot water return.

Diameter callouts are written on or beside the pipe, e.g., '3 V' means a 3-inch vent and '4 D' means a 4-inch drain.

Slope is shown as inches per foot or percent; on an isometric the flow direction is indicated by an arrow pointing downhill toward the drain or sewer.

Horizontal-to-horizontal drainage changes use a wye or a combination wye-and-eighth bend; vertical to horizontal uses a sanitary tee or wye.

Isometrics must be read together with the plan and a north reference; risers are the vertical segments that reconnect separate floor plans.

The pressure at a fixture inlet must be at least 8 psi flowing; where static pressure exceeds 80 psi, a pressure-reducing valve is required.

Where the street pressure is inadequate for the fixture demand, an approved booster pump or on-site pressure tank must be provided.

A closed water system (created by a check valve, backflow preventer, or pressure-reducing valve) requires thermal expansion control.

Minimum water service pipe size is 3/4 inch; fixture supply branches are minimum 1/2 inch, with 3/8 inch permitted only for certain small fixtures.

Flushometer valves require larger, dedicated branch sizing than flush-tank fixtures and cannot be installed where the available flowing pressure is insufficient.

Hot water distribution must be insulated where required by the energy code, and hot water piping is run above cold water where pipes are parallel.

Water hammer arrestors are required at quick-closing valves and at fixture groups with fast-acting flush valves.

Water piping must be protected from freezing and supported at intervals required by code for the pipe material.

Water distribution sizing uses the total water-supply fixture units and the developed length from the meter to the most remote outlet.

Copper water tube: Type K is used underground and in heavy-duty service, Type L above ground for domestic water, Type M only where permitted.

PEX must be listed to ASTM F876/F877 with fittings to ASTM F1807 or F1960; PEX-A is expanded, PEX-B is crimped.

DWV materials: PVC to ASTM D2665, ABS to ASTM D2661, service-weight cast iron to CISPI 301, copper DWV tube to ASTM B306.

Hubless cast iron joints use couplings complying with CISPI 310 and stainless steel shields.

Galvanized steel pipe must comply with ASTM A53; threaded joints use at least Schedule 40 pipe.

Solder and flux must be lead-free; lead content in pipe, fittings, and solder is limited to not more than 0.25 percent by weight.

Drainage piping shall not be reduced in size in the direction of flow; water piping is sized so velocity stays within limits that prevent noise and erosion.

Maximum fixture flow rates: water closets 1.6 gpf, urinals 1.0 gpf, showerheads 2.5 gpm at 80 psi, kitchen and lavatory faucets 2.2 gpm, public lavatory faucets 0.5 gpm.

Water closet compartment: not less than 15 inches from the centerline of the fixture to a side wall and 21 inches of clear space in front.

Accessible fixtures require clear floor space of 30 inches by 48 inches and comply with the adopted accessibility standard.

Fixtures must be of an approved type, with a smooth, impervious, corrosion-resistant surface, and securely fastened to the floor or wall.

Floor drains are required in public toilet rooms and in locations where water or a fixture leak could cause damage.

Drinking fountains must be capable of delivering at least 0.25 gpm and provide a minimum number based on occupant load.

Shower compartments must have a minimum finished interior area of 900 square inches and be finished with a smooth, impervious surface.

Food service establishments require a sink with at least three compartments for washing, rinsing, and sanitizing.

Hose bibbs and sill cocks require an approved backflow preventer such as a vacuum breaker.

Shower valves must be pressure-balancing, thermostatic, or combination type, and must limit the delivered water temperature to a maximum of 120 degrees F.

A bathtub filler spout must be located at least 2 inches above the overflow rim of the tub.

Faucets and supply stops must be listed and installed so that the fixture can be isolated for repair.

Escutcheons are required where supply or drain pipes pass through a wall or floor in a finished area.

Flushometer valves require a minimum flowing pressure stated by the manufacturer and code and are installed with a control stop and vacuum breaker.

Fittings with slip joints are limited to the trap and fixture connection and must be accessible.

Every water heater requires a temperature and pressure relief valve that is third-party listed and rated for the heater's capacity.

T&P relief discharge must be full size, gravity-flow, terminate not more than 6 inches above the floor or outside the building, and must not be trapped or have a threaded end.

A drain pan at least 1.5 inches deep with a drain of not less than 3/4 inch is required where leakage may cause damage, such as in an attic or above a ceiling.

The relief valve discharge pipe must not be reduced in size and must not contain a valve between the heater and the valve or in the discharge.

A water heater installed in a closed system requires a thermal expansion tank or other approved expansion control.

Gas-fired water heaters require combustion air, a sediment trap ahead of the controls, and venting sized to the appliance input.

Water heaters must be accessible for service and inspection, and the T&P valve must be accessible for testing and replacement.

Heaters installed in areas subject to vehicle damage require protection such as bollards.

A pressure-reducing valve is required where static pressure exceeds 80 psi; typical settings reduce the downstream pressure to 50-75 psi.

A PRV creates a closed system, so thermal expansion control is required downstream of it.

Water delivered to public lavatories and showers must not exceed 120 degrees F unless a limiting device is provided.

Tempered water for public hand-washing is delivered at approximately 110 degrees F using a thermostatic or tempering valve.

A typical T&P relief valve is set to open at 150 psi and 210 degrees F.

Water hammer arrestors are sized to PDI WH-201 and installed at quick-closing valves and flushometer groups.

A strainer must be installed ahead of a pressure-reducing valve, and the valve must be accessible with a downstream pressure tap.

Horizontal drainage piping slopes at least 1/4 inch per foot for pipe 2 1/2 inches and smaller and 1/8 inch per foot for pipe 3 inches and larger.

The building drain is the lowest piping of the drainage system that receives waste from inside the building and conveys it to the building sewer.

Each horizontal drain requires a cleanout at its upper end, and cleanouts are required at the base of each stack and at changes of direction greater than 135 degrees.

Cleanouts are required at intervals not exceeding 100 feet in horizontal drainage piping and must be accessible.

A backwater valve is required where a fixture's flood-level rim is below the elevation of the next upstream manhole.

Drainage fittings must have smooth interior surfaces; a sanitary tee is used for vertical-to-horizontal transitions, and wyes for horizontal-to-horizontal.

Vertical drainage stacks must be supported at their base and at intervals required by code, with no reduction in size in the direction of flow.

Fixtures must be protected from sewer gas and backflow by traps and, where required, backwater valves.

Drainage pipe is sized from the total drainage fixture units (dfu) on the line using the code's drainage sizing tables.

Minimum slope: 1/4 inch per foot up to 2 1/2 inch pipe; 1/8 inch per foot for 3 inch and larger pipe.

The building sewer and building drain must be not less than 3 inches in diameter.

Trap arm length limits: 1 1/4 inch trap = 5 feet, 1 1/2 inch trap = 6 feet, 2 inch trap = 8 feet from the trap weir to the vent.

A drainage line may slope steeper than the minimum, but an excessive slope on short runs can leave solids behind; vertical drops are connected with a wye and bends.

Pipe size is never reduced in the direction of flow, and the slope must be uniform between fittings.

Storm drainage is sized on roof area and rainfall rate and uses the same minimum slope rules as sanitary drainage.

Insufficient slope causes solids deposition; reverse slope (falling toward the fixture) is prohibited.

Every trap must be protected from siphonage by a vent, except where the code specifically permits an unvented fixture or common vent arrangement.

The minimum size of an individual vent or vent stack is 1 1/4 inches; a vent may never be smaller than 1 1/2 inches where required for the drainage it serves.

A vent must be taken off at least 2 pipe diameters from the trap weir, which prohibits a crown vent.

A vent stack must extend at least 6 inches above the roof surface and be flashed to prevent leakage.

Vents must be sized by the number of fixture units served using the vent sizing tables, and a vent cannot serve as a drain.

Wet venting is permitted only where the wet-vented fixture is on the same floor and the vent is sized per the tables.

Air admittance valves are permitted only where approved by the AHJ, are installed above the fixture flood-level rim, and require access.

A vent must extend upward without offsets below the fixture, and horizontal vent runs must slope back toward the drain.

Each fixture must be separately trapped, except fixtures with integral traps and where a single trap is permitted by code.

A water closet has an integral trap and does not require an additional trap.

A trap seal must be between 2 inches and 4 inches deep, and the trap must be self-cleaning.

Trap sizes: minimum 1 1/4 inch for lavatories, 1 1/2 inch for sinks, and 2 inches for other fixtures such as floor drains.

A trap must be level (horizontal) after installation, and the trap arm length limits apply from the trap weir to the vent.

S-traps, crown vents, double traps, and traps that depend on moving parts for their seal are prohibited.

Traps must be accessible for cleaning, either by location or by a removable cleanout/fixture.

Trap seals can be lost by evaporation, siphonage, backpressure, or capillary action; venting and proper installation prevent most seal loss.

Grease interceptors are required for restaurants and other establishments that discharge grease-laden waste from food preparation or dishwashing.

Grease interceptors are sized by the fixture-capacity or flow-rate method; mass-produced units must be listed to PDI G101.

Interceptors must be installed with a vent, an accessible cover, and a cleanout for removal of accumulated grease.

The grease interceptor must be located so that accumulated grease can be removed and the unit inspected; it is commonly installed outside the building.

Sand and oil interceptors are required for garages, repair shops, and car washes where sand, oil, or similar materials enter the drainage system.

The discharge from an interceptor must connect to the sanitary drainage system through a vented line with a full-size cleanout.

Interceptors must retain a water seal and must not be double-trapped or installed where they can be siphoned.

An air gap is the only method that protects against both backsiphonage and backpressure; it must be at least twice the pipe diameter and never less than 1 inch.

A reduced pressure zone (RPZ) assembly protects against both backpressure and backsiphonage and is required for high-hazard connections; it must be field tested.

A double check valve assembly (DCVA) is used for low-hazard connections and protects against backpressure and backsiphonage.

A pressure vacuum breaker (PVB) protects against backsiphonage only and must be installed at least 12 inches above the highest downstream outlet.

An atmospheric vacuum breaker must be installed at least 6 inches above the flood-level rim and must not have a shutoff valve downstream.

Backflow protection is required at boiler feed lines, irrigation systems, hose bibbs, carbonators, chemical dispensers, and lawn sprinklers.

Backflow assemblies must be installed in an accessible location for testing and must be tested by a certified backflow tester.

A bypass around a backflow assembly is prohibited unless the bypass is equipped with an approved backflow device.

Storm drainage must be kept separate from the sanitary drainage system and discharge to an approved point such as a storm sewer, dry well, or splash block.

Roof drains and leaders are sized from the roof area and the local design rainfall rate, not from fixture units.

Minimum roof drain size is 2 inches, and storm drainage uses the same minimum slopes as sanitary drainage.

Primary and secondary (overflow) roof drains are required on roofs with parapet walls so that water can escape if the primary drain clogs.

Roof drain strainers must be provided and the drain must be flashed to the roof to prevent leakage.

Storm drainage must not discharge into a sanitary sewer unless specifically allowed by the authority having jurisdiction.

Subsoil drains and sump pumps discharge to an approved location and may not connect to the sanitary system where prohibited.

Indirect waste is waste that discharges into the drainage system through an air gap or air break into a properly sized and vented receptor.

An air gap must be at least twice the effective pipe diameter and never less than 1 inch; an air break requires the pipe to terminate above the flood-level rim of the receptor.

Indirect waste is required for food service sinks, dishwashing machines, ice machines, coffee brewers, sterilizers, and similar equipment.

Receptors must be individually trapped and vented and must be large enough to receive the discharge without splashing.

Special wastes include chemical wastes, which require acid-resistant piping, and condensate, which may discharge to an approved receptor.

Clear-water wastes such as condensate from air conditioning and relief valve discharge are discharged by indirect waste.

Food waste grinders and pot sinks must drain through an air gap or air break before entering the drainage system.

Gas piping is sized using the longest-length method with the code's capacity tables for the specific pipe material and gas.

A sediment trap is required at each appliance inlet, installed upstream of the controls with a minimum 3-inch nipple.

A shutoff valve must be installed ahead of each appliance in the same room and must be accessible.

An appliance connector must not exceed 6 feet, must not be concealed, and must not pass through a wall, floor, or ceiling.

Gas piping must be supported at code intervals, protected against corrosion, and identified where it passes through concealed spaces.

Metallic gas piping must be bonded to the grounding electrode system; gas piping may not be used as a grounding conductor.

Combustion air for fuel-burning appliances is provided by indoor air (50 cubic feet per 1,000 Btu input) or by outdoor openings sized per the code.

New gas piping is pressure tested with air or nitrogen, and leaks are checked with soap solution, never with an open flame.

Trenches 5 feet deep or more require shoring, shielding, or sloping, and a ladder must be provided within 25 feet of lateral travel.

Spoil piles and equipment must be kept at least 2 feet from the edge of an excavation.

Confined spaces must be tested for oxygen, hydrogen sulfide, and combustible gas before entry, and ventilation must be provided.

Hydrogen sulfide in sewers is toxic and explosive at high concentrations; sewer gas must be controlled with ventilation and monitoring.

Ground-fault circuit interrupter protection is required for temporary power on construction sites.

Hot work with a torch requires a fire watch, removal of combustibles, and adequate ventilation of flux fumes.

Fall protection is required when working 6 feet or more above a lower level.

Copper tube must be reamed to full inside diameter after cutting to prevent turbulence and flow restriction.

A pipe wrench is operated by pulling the handle toward the user with the jaws facing the direction of rotation.

Cast iron soil pipe is cut with a soil pipe cutter or snap cutter, and the cut end is dressed before coupling.

Press fittings require a calibrated press tool with the correct jaw for the fitting size and material.

PEX-A is expanded with an expansion tool; PEX-B is joined with a crimp or clamp tool.

A hydrostatic test pump is used to pressure-test water distribution systems.

A closet auger is used for water closets; a drum or sectional cable machine is used for larger drain lines.

Drainage slope is set with a level, laser, or transit; a grade rule is used to check fall per foot.

DWV systems may be tested with water, using a 10-foot head above the highest point of the system, held for at least 15 minutes without a drop.

DWV systems may alternatively be tested with compressed air at 5 psi for at least 15 minutes with the system isolated.

Water distribution systems are tested hydrostatically at working pressure or the code minimum, held for at least 15 minutes without leakage.

The building sewer is tested with water or air before being covered, and the test is witnessed by the AHJ.

Rough-in inspection must be approved before piping is concealed, and final inspection occurs after fixtures and trim are set.

Open pipe ends must be capped or plugged during construction to keep debris out of the drainage system.

Test results and inspections are recorded, and the AHJ may require a re-test whenever work is altered after approval.