Page | 1
NHIE Home Inspection Manual:
Plumbing System Study Questions with
Detailed Verified Answers
Question: What are plumbing freeze protection requirements?
Ans: In locations subject to freezing:
- pipes should be insulated in attics, crawls spaces, & exterior walls
- service pipes should be installed a minimum of 12-in. or 6-in below frost
line (whichever is deeper)
Question: When should plumbing be protected when passing through
framing members?
Ans: Pipes installed through house or notches (e.g., studs, joists, rafters)
should:
- be protected against puncture w/steel plates
- be installed when pipe is closer than 1 1/2 in. from edge of member
- have a plate which extends 2-in above and below pipe
Question: What are hole requirements when passing through framing?
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Ans: Holes for pipes should be:
- large enough to allow pipes to move
- about 1/2 in larger than pipe diameter
Note: too smalls holes result in squeaking, rubbing and clicking of pipe
against framing
Question: How should pipes pass through foundation walls?
Ans: Pipes through foundations walls:
- should be protected against breaking by a relieving arc or a sleeve
- should have sleeves 2 sizes bigger than pipe
- should pass through sleeve sealed with waterproofing material (e.g.,
caulk, foam, or gasket)
Question: How should pipes be supported?
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Ans: Material should be:
- sturdy enough to support pipe full of substance
- wide enough to support pipe without crimping material
- a compatible material with pipe (e.g., no copper hangers for steel, etc.)
Question: What are the minimum and maximum size of residential service
pipes?
Ans: Answer:
- min size 3/4 in.
- max size 1 1/2 in.
- average size 1 in.
Question: What are the three types of copper tubing used in residential
construction?
Ans: Answer:
- Type K: thickest wall; green markings;
- Type L: Thinner wall; blue markings; &
- Type M thinnest wall: red markings.
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Question: What is the typical service life of copper tubing?
Ans: Answer:
- Depending on site conditions, it can be as little as 20 years or more than
50 years.
Question: What are the installation requirements of copper?
Ans: Copper tubing:
- should be supported horizontally every 6 ft.
- should be protected against punctures, corrosion, breaking, and freezing
- (Type K & L) can be installed underground and embedded in concrete
- (Type M) can be installed underground but not embedded in concrete
Question: What are the copper connection requirements?
NHIE Home Inspection Manual:
Plumbing System Study Questions with
Detailed Verified Answers
Question: What are plumbing freeze protection requirements?
Ans: In locations subject to freezing:
- pipes should be insulated in attics, crawls spaces, & exterior walls
- service pipes should be installed a minimum of 12-in. or 6-in below frost
line (whichever is deeper)
Question: When should plumbing be protected when passing through
framing members?
Ans: Pipes installed through house or notches (e.g., studs, joists, rafters)
should:
- be protected against puncture w/steel plates
- be installed when pipe is closer than 1 1/2 in. from edge of member
- have a plate which extends 2-in above and below pipe
Question: What are hole requirements when passing through framing?
, Page | 2
Ans: Holes for pipes should be:
- large enough to allow pipes to move
- about 1/2 in larger than pipe diameter
Note: too smalls holes result in squeaking, rubbing and clicking of pipe
against framing
Question: How should pipes pass through foundation walls?
Ans: Pipes through foundations walls:
- should be protected against breaking by a relieving arc or a sleeve
- should have sleeves 2 sizes bigger than pipe
- should pass through sleeve sealed with waterproofing material (e.g.,
caulk, foam, or gasket)
Question: How should pipes be supported?
, Page | 3
Ans: Material should be:
- sturdy enough to support pipe full of substance
- wide enough to support pipe without crimping material
- a compatible material with pipe (e.g., no copper hangers for steel, etc.)
Question: What are the minimum and maximum size of residential service
pipes?
Ans: Answer:
- min size 3/4 in.
- max size 1 1/2 in.
- average size 1 in.
Question: What are the three types of copper tubing used in residential
construction?
Ans: Answer:
- Type K: thickest wall; green markings;
- Type L: Thinner wall; blue markings; &
- Type M thinnest wall: red markings.
, Page | 4
Question: What is the typical service life of copper tubing?
Ans: Answer:
- Depending on site conditions, it can be as little as 20 years or more than
50 years.
Question: What are the installation requirements of copper?
Ans: Copper tubing:
- should be supported horizontally every 6 ft.
- should be protected against punctures, corrosion, breaking, and freezing
- (Type K & L) can be installed underground and embedded in concrete
- (Type M) can be installed underground but not embedded in concrete
Question: What are the copper connection requirements?
