Plumbing Flashcards
How does water flow into the home to fixtures/appliances?
potable water from public comes through the water service pipe into the home and is distributed through the water distribution pipes which begins at the main water shutoff valve
grey water
waste water from sinks, tubs, and showers used to flush toilets or irrigate landscaping
What components of a home’s plumbing system are NOT in scope of a home inspection
washing machines & their connections, sewage disposal systems, fire suppression/fire sprinkler
3/4 bathroom
bathroom w/ sink, toilet & shower (no bathtub)
aerator
device that controls air into water stream, found on sinks and lavatory faucets
air admittance valve (AAV)
air pressure operated one way valve used in place of an atmospheric plumbing vent; device different from check vent which contains spring loaded gasket
backpressure
occurs when the pressure at a point outside the water supply system is greater than the water supply system pressure (uncommon)
backsiphonage
occurs when there’s negative pressure in the water supply system pipes and contaminants are possibly sucked into the water supply system pipes.
-Occurs because of sudden loss of water pressure combined with rapid drainage of water supply sys. pipes.
backwater valve
a type of check valve that prevents sewage from public water flowing into house.
-Recommended when plumbing fixtures in house are located below nearest upstream manhole cover of the public sewer.
*installed where recommended and same size as bldg sewer pipe and accessible.
water hammer
thumping/banging noise caused by sudden stopping of water flow.
-can damage pipes/fixtures.
water hammer arrestor
device that absorbs the hydraulic shock caused by sudden stopping of water flow, usually installed near clothes washing machine/dishwasher water supply connetions.
Pipes installed through holes and notches should be…
-be protected against puncture from nails/screws by installing steel shield plates if edge of hole/notch is closer than 1 1/2” to the edge of the member. Shield plate should extend 2” above bottom plate and below top plate.
-large enough to allow pipes to move w/ hole at least 1/2” larger than the pipe diameter to avoid rubbing/clicking/squeaking against framing materials.
Pipes installed through foundation walls or installed under a footing should be protected against breaking by…
breaking by a relieving arch or enclosing the pipe in a sleeve. Sleeve should be 2 sizes larger than pipe.
What could be the cause of inadequate functional flow at plumbing fixtures?
-blocked aerator or blocked flow restrictor
-pipes reduced internal diameter b/c of rust, dirt, etc.
-occasionally could be inadequate pipe size (H.I. not req’d to determine if correct)
Water service pipe must be a minimum of _____?
3/4” inch
what is copper tubing used for?
water service and distribution.
used since 1930s, widespread use in 1950’s as main water distribution (until PEX tubing now)
Copper tubing comes in three types that are commonly used in houses. Type __ has the thickest walls and is identified with ______ markings. Type __ has thinner walls than Type K and is identified with blue markings. Type __ has the thinnest walls and is identified with ___ markings.
K, green
L
M, red
Copper tubing should be supported horizontally at least every ________ and vertically every ________.
6 feet; 10 feet
*should be protected against punctures, corrosion, breaking/freezing
Identify where copper tubing Types K, L, and M can be installed? What connections are used with copper tubing?
Types K and L - installed above or below ground, embedded in or installed under concrete/masonry. can be used for natural gas or fuel oil (no fuel in some jurisdictions).
Type M - installed above or below ground. but MAY NOT BE embedded or installed under concrete/masonry
copper to copper using soldered copper fits, threaded fits or push-connect fits. Need dielectric fits to avoid galvanic corrosion.
galvanic corrosion
when 2 metals meet in the presence of water. weakens the materials causing potential leak
(“occurs when electrons flow between dissimilar metals in presence of an electrolyte.”)
max water pressure of residential home?
80 psi (pounds per square inch)
What’s PVC used for?
DWV, water service, & irrigation.
PVC -> cold water ONLY - 100 degree max temp.
What’s CPVC and what is it used for?
Chlorinated polyvinyl chloride -
Water distro & water service pipe
thermoplastic pipe usually cream color (sometimes w/ yellow stripe or colored grey) w/ max temp of 180 degrees
Chlorinated Polyvinyl Chloride pipe should be supported horizontally every _____ and vertically every _____. Midstory guide for pipes _____ or smaller. These type of pipe should be connected using ________.
They should protected against _______
3 feet; 10 feet
2 inches
solvent cement (glue)
*protected against punctures, breaking, freezing. Vulnerable to cracking when water freezes inside.
What material pipe can be used for water heater pressure relief valve?
copper or CPVC.
CPVC pipe is usually connected using…
solvent-cemented fitting, push-connect or threaded fitting if connected to other CPVC.
to copper or PEX using push-connect fitting or threaded adapter fitting.
to galvanized steel using threaded adapter fitting
Issues with CPVC are usually caused by?
-improper installation (using wrong or incorrect amount of solvent cement, improper support)
-freezing
*no reported SYSTEMIC problems
What is galvanized steel pipe used for?
water service (uncommon), water distro, & DWV
dull gray color or black steel pipe; 1860s-1960s most common.
no longer used in homes except to repair/replace existing galv. steel
Explain the issues with galvanized steel pipe?
rusts from the inside out (weakens then leaks). Inside surface traps particles and rust in the water.
reduced functional flow due to reduction in inside of pipe. water may have rust color.
Galvanized steel pipe should be supported horizontally every ______ and vertically every _______.
12 feet; 15 feet
protected against breaking and freezing.
Galvanized steel pipe fittings are:
threaded fittings connected to other galv. steel.
threaded adapter fitting to CPVC and PEX.
using dielectric fitting or brass fitting if connected to copper tubing.
Where does the water distribution “start” in a residential home?
main water shut off
What weakens PEX tubing?
degrades when exposed to sunlight
weakened by chlorine
Polybutylene tubing must be supported every ____ and _____.
32” inches horizontally; 4’ feet vertically.
Used for water distribution and water service
PB is a problematic system.
What is the maximum water temperature in a residential home?
120 degrees F.
AAV
air admittance valve - air pressure operated one-way valve used in place of atmospheric plumbing vent.
*device is diff from a check vent!!
What’s in scope in a plumbing inspection?
-interior water distribution
-interior drain, waste, and vent systems
-plumbing fixtures and appliances (faucets, toilets, sinks, water heaters, on site fuel storage/distribution, sewage ejectors, sump pumps, and all associate pipes and/or vents
What’s NOT in scope of home inspection?
clothes washing machine and connections
private water supply systems
private sewage disposal systems
fire suppressions/fire sprinklers
(and components located outside the home related to these)
What’s the role of the water service pipe?
bring water into the home.
What’s the maximum water pressure in a residential home?
80 psi
Water pressure exceeding 90 psi should be reduced by installing water pressure regulator in water srvc. pipe
During an inspection, you observe inadequate functional flow at plumbing fixtures, what is most likely the cause of this?
blocked aerator or blocked flow restrictor.
could be caused by galv. steel pipes
-or-
reduced diameter
inadequate pipe size
Water distribution pipes installed through holes or notes should be protected against puncture by installing __________
Shield plates.
if the edge of hole is closer than 1 1/2” to edge of member. Shield plate should extend at least 2” above bottom plate and below the top plate.
Holes and notches through which water distribution pipes are installed should be _______ to prevent rubbing/clicking against framing materials.
1/2” inch larger than the pipe diameter.
Pipes installed through foundation walls should ______________.
be installed in a sleeve that protects against breaking by a relieving arch.
Sleeve should be 2 sizes larger than pipe installed thru wall. Space between pipe and sleeve should be sealed w/ waterproof caulk/foam/gasket.
Pipe support material should be wide enough so the pipe is not crimped, be sturdy enough to support the pipe when filled, and should also be _______ with the pipe material.
compatible.
Copper hangers shouldn’t support galv. steel pipe and steel straps shouldn’t support copper pipe.
(T/F) Home inspectors are required to determine if pipe sizes are correct.
False. HI are NOT required too.
What are some reported problems with copper tubing?
patina needs to remain in tact; can be damaged by aggressive water or water too alkaline or acidic.
excessive water velocity or pressure scours the coating off the tubing. excessive use of acidic solder flux during installation.
CPVC should be used for _______. It should be supported every _____ horizontally and every ______ vertically with a ________________ for pipes 2” or smaller.
water service and for water distribution. (can also be used as water heater temperature/pressure relief valve extension pipe.)
3’ ft; 10’ ft
midstory guide for pipes 2” or smaller.
water sWhat is CPVC vulnerable to? How should it be connected to other pipes?
most vulnerable to cracking when water freezes inside.
should be protected against punctures, breaking and freezing.
Connected to other CPVC using solvent cemented fittings, threaded fitting or push-connect; connected to copper/PEX using push connect or threaded adapter fitting; connected to galv. steel using threaded adapter.
Galv. steel is used for what?
water service, water distro and DWV.
dull gray color.
Galvanized steel should be connected to other pipes using what connections?
What are the main problems with galvanized steel?
threaded fittings to over galv. steel; to CPVC and PEX using threaded adapter fitting
Rusts from inside out which causes reduced flow.
How should PEX be connected to other tubing?
copper or brass rings that are crimped to the PEX and fitting using crimping tool; to copper/CPVC using push-connect.
What are some issues with pex tubing?
degrades/weakens with chrlorine in water. shouldn’t be exposed to sunlight (incl/ attics/crawl spaces w/ vent openings)
What’s PB tubing and whats it used for?
polybutylene used for water service and distro.
thermoplastic, blueish gray or cream.
supported every 32” horiz. and 4’ ft vert.
What (if any) are the issues with PB tubing?
it’s a problematic sys; issues relating to fittings! Also, known to degrade when exposed to sunlight.
What’s a water connector and what are the rules for using it?
short length (12-60”) tubing that connects water distro pipes to fixtures/appliances
(plastic tubing should have listing info on tubing)
-shouldnt be linked together
-shouldn’t be bent to reduce internal diameter
-shouldn’t go thru walls, floors, or ceiling
-shouldnt be used as TPR valve ext. pipe
-shouldnt be used as sub for water distribution pipe
(T/F) every dwelling should have a full open gate type valve near the water service pipe entering the home. Water heaters should have full-open valves on cold water supply.
True.
Full open valves: ball valve, gate valve
Hose connections that are subject to freezing should have ___________.
stop and waste valve or a frost proof hose connection faucet
Silk faucets maximum water flow rate?
Shower faucet maximum water flow rate?
2.2 gal/min
2.5 gal/min
Low flow at sink/shower often result of blocked aerator or flow restrictor.
At a sink/lavatory the hot water should be represented by the _______ handle and the cold water should be represented by the ________ handle.
hot is on the left, cold is on the right,
A bathtub should be drained after every use while a hydromassage tub (whirlpool) is different because…
not for personal use and has a pump/motor. Used for recreation and not drained after every use.
bathtub drain should be a minimum of _________
1 1/2” inches
common bathtub dimensions are 30 x 60 inches
30” x 60” inches
When inspecting a whirlpool tub, what should you do/look for?
Do not operate the pump until the water is above the highest jet. Use the pump for several minutes. Find and operate the GFCI. DO NOT LEAVE THE ROOM while filling a tub.
What is the minimum access opening for whirlpool pump access?
min clear opening is 12”x12” inches
min clear opening is 18”x18” if pump is more than 2’ ft from the opening.
(should be no obstructions between opening and pump that hinder repair/replacement.)
What is the minimum shower drain outlet size?
1 1/2”
p-trap under shower. Fixture drain length should be 6’ ft long for 1 1/2” trap; no more than 8’ ft for 2” trap.
what is the minimum shower size?
30 inches; floor area not less than 900 sq. inches (circular diameter)
25” if finished floor total less than 1300 sq. inches
Shower ceiling height shouldn’t be less than ________ in a 30x30” under shower head. Finished shower access opening minimum is _______.
80” ceiling height
22” inches for finished access opening
What’s the minimum shower clearance in front of shower?
24” minimum opening in front of shower (like how a door would swing)
Minimum shower curb?
9” tall at minimum, if curb exists.
Shower floor should be slip resistant and slope towards the drain at not less than ______________
not less than 1/4 inch per foot and not more than 1/2 inch per foot.
Shower walls should extend at minimum _______ above the shower floor.
72”
What is the minimum clearance in front of a toilet? Clearance to each side of toilet?
What is the minimum clearance in front of a silk? Clearance to each side of the sink?
21” in front of toilet/bidet; 15” to side of toilet (measure from center of toilet)
21” in front of a sink; 15” to side of sink (measured from center sink)
The minimum bathroom sink (lavatory) drain outlet size is _________.
1 1/4”
What is the minimum bathroom height ceiling?
84” inches minimum bathroom ceiling height
A sink outlet should not be more than _______ horizontally and ______ vertically from the trap inlet.
30” horizontally; 24” vertically
A temperate limiting device should limit the temperature of water on a bidet to
110 degrees F.
Floor drain traps should be at least _______ in diameter
2” inches in diameter
What is a trap primer?
device that injects small amount of water into trap on reg. basis
(floor drains trap should be connected to trap primers.)
Whats the purpose of a backflow preventer?
keep harmful materials out of potable water supply
When does backsiphonage occur?
When water is drawn into water supply pipes by negative pressure in the pipes
When does backpressure occur?
When pressure of the contaminate source exceeds the pressure in the water supply pipes.
Backflow is prevented by 2 methods which are:
air gap or a mechanical device to prevent backflow (ex. hose connection vacuum breaker)
(T/F) The water supply for a lawn irrigation system should be protected by a backflow preventer
true
(in places subject to freezing a pressure vacuum breaker is used in place of backflow preventer above ground.)
Whats the difference between a driven well vs a drilled well?
Driven well is bored by pounding pipe into loose water bearing sand/gravel. Shallow (50+ ft)
Drilled well bored by using methods and equipment. Deep as necessary to reach aquifer.
The well head should be located a minimum of how far from these locations:
septic tank and it’s leach field:
petroleum tanks and areas with pesticides/herbicides/fertilizers:
Well head should be at least 50 ft from septic tank & its leach field
Well head should be at least 100 ft from petroleum tank and pesticides/herbicides/fertilizers
The well head should be about _____________ above grade and and grade should slope _____ from well head. Well should be ____________.
12-18” inches above grade, grade should slope away from well head.
Well should be capped and sealed.
Water heaters installed in a garage should be _______ above the garage floor and should be protected from ___________.
ignition source should be 18” above garage floor
vehicle impact
The TPR valve activates at ________; _______. Minimum diameter of a TPR valve is _____.
150 PSI; 210 degrees F
3/4” inch
Seismic bracing straps should be attached in the upper and lower third of a water heater and should not interfere with service openings, with straps at minimum of _ from controls.
4”
A thermal expansion tank is recommended when the water system is _________.
closed
Tempering (mixing) valves are designed to ?
limit the temperature of water flowing through fixtures fo 120 degrees F
What is the smallest size drainage pipe from a toilet?
3”
3” is smallest drain pipe that may leave bathroom.
Pipes smaller than 3” should slope ____________.
Pipes larger than 3” should slope ____________.
no less than 1/4”.
no less than 1/8”.
A gas fired storage tank water heater is a what category appliance?
Category I
(hot gasses vent via stack effect)
Acrylonitrile Butadiene Styrene (ABS) is used for what? Should be supported every _____ and ______ vertically.
building sewer and interior DWV. can be water srvc. but not water distribution.
4’ ft; 10’ ft
protected against punctures, corrosion, breaking, freezing.
How should Acrylonitrile Butadiene Styrene be connected?
to other ABS: solvent cement or threaded fittings
to PVC: adapter fitting w/ materials from both fittings. Transition cement used to connect adapter.
to galvanized steel: using banded couplings that use stainless steel bands to secure the joint (elastomeric couplings)
What’s cast iron pipe used for? What are the supports and connections?
building sewer and interior DWV.
supported horizontally10’ ft if 10’ ft long pcs used, otherwise 5’ when fittings installed; vertically every 15’ ft
protected against breaking and freezing protection (no punctures)
connected to other cast iron using hubs and spigots and/or caulked joints OR newly: elastomeric commpression gaskets or banded coupling
connected to ABS,PVC, galv steel using caulked joint, compression gasket or banded coupling.
cast iron to galv. steel using threaded adapter fitting
Whats a reported problem with cast iron pipes?
rusts from inside and at end of life pipe walls rust (rust cysts), break or leak (esp. at joints)
rust inside blocks water flow.
Clay pipe is used for what? How is it connected?
used for building sewer but not anymore. problems with breaking/blockage via plant roots.
connected using bell (hub) and spigot system. modern connections incl/ compression gaskets and banded couplings.
Orangeburg sewer pipe is used for ______ only. Not common piping but if found typically a entire neighborhood may use the piping.
building sewer
Polyvinyl chloride (PVC) is used for:
building sewer pipe and interior DWV.
water service only, 100 degrees or less.
Polyvinyl chloride should be supported every ______.
10’ ft horizontally. Midstory guide 2” or smaller.
protected against freezing breaking punctures corrosion.
polyvinyl chloride is connected using:
solvent cement to PVC. (primer req’d). or threaded fittings
PVC to ABS using adapter fitting along w/ transition cement.
Vent pipes should slope ________________________
downward toward the discharge point.
A ______ deals with sewage. The _______ deals with storm water or subsurface water that finds its way into or around the foundation of the home.
sewage ejector
sump pump
The pit in a sewage ejector system should be:
18” inches in diameter; 24” inches deep, installed on level base.
Discharge pipe minimum of 2” inches
minimum vent pipe size is 1 1/4”
(AAV cannot be used as vent for sewage ejector.)
a sump pump system consists of what components?
sump pit, pump, discharge pipe, check valve, and electric power
sump pit doesnt need lid unless in radon prone area. check valve is a new requirement. discharge pipe should be approved for DWV (ABS, copper, PVC).
Black Steel gas pipe supports are:
horizontal:
every 6’ ft for 1/2” pipe
every 8’ ft for 3/4” & 1” pipe
every 10’ ft for 1 1/4” or larger pipe
NO copper hangers - metal hangers, straps or clamps.
black steel gas pipe joints are:
threaded. connected at joint compound with pipe joint compound (pipe dope) or YELLOW teflon tape
Pipes should be at least Schedule 40
(NO white teflon tape can be used for gas pipes!)
The difference between corrugated stainless steel tubing and flexible appliance connectors is that…
CSST (corrugated stainless steel tubing) is a gas distribution system whereas FAC (flexible appliance connectors) are for connecting gas supply to an appliance.
The minimum vent pipe size is ________ or half the diameter of pipe being vented whichever is larger.
1 1/4” (largest usually 1 1/2”)
A sediment trap’s purpose is to _____.
A drip tee/drip leg’s purpose is to ____.
sediment trap is to keep debris from entering gas appliance and restricting gas flow through orifice. (should be installed near appliance; downstream from shutoff valve)
drip tee to keep moisture from entering gas appliance and fouling/rusting appliance.
