Mock paper #4

NASCLA Accredited Examination for Commercial General Building Contractors

A full paper drawn to the blueprint. Answers and worked explanations are at the back of this file.

Questions: 115
Time: 330minutes
Mark: 70%to pass
Paper: #4of 5

Single-user licence. You may print this file and write on it. You may not redistribute, resell or post it. © Sitonce 2026.

Before you start

Sit this the way you will sit the real one. A mock done in pieces over three evenings measures your notes, not your recall.

Questions

115

Minutes

330

Per question

172s

Started at

Set a timer for 330 minutes and do not stop it. Running over is the commonest way a prepared candidate fails, and the only place you can find that out safely is here.
Mark one answer for each question on the answer sheet.
Answer every question. There is no penalty for a wrong answer. A blank is a guaranteed zero and a guess is not.
Flag anything you are unsure of as you go. When you mark the paper, a question you flagged and got right is worth as much of your attention as one you got wrong - you do not yet know it, you guessed it.
When the timer runs out, turn to the Answers section at the back of this file. Mark the paper against the quick-reference key first, fill in the score table, and only then read the worked explanations.

What this paper covers

Area	Questions	Share
Procurement and Contracting Requirements	31	27%
General Requirements	25	22%
Site Construction	15	13%
Concrete	6	5%
Mechanical and Plumbing Systems	6	5%
Metals	6	5%
Finishes	5	4%
Thermal and Moisture Protection	5	4%
Wood	5	4%
Doors, Windows and Glazing	4	3%
Masonry	4	3%
Electrical Systems	3	3%
Total	115	100%

Pass mark vs pass rate

The pass mark is 81 correct out of 115 scored questions, which PSI publishes. Any pass-rate figure quoted for this exam is an estimate - neither NASCLA nor PSI publishes one.

Answer sheet - paper #4

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Paper #4

115 questions. 330 minutes.

1

When is a fire pump required?

AWhen the water supply cannot meet the system's required pressure and flow
BWhenever a dry pipe system is installed in place of a wet one anywhere in the building
CIn every building fitted with an automatic sprinkler system
DIn every building over three storeys in height

2

What is the maximum arresting force a personal fall arrest system may apply to a worker?

A5,000 pounds, matching the anchorage strength requirement
B900 pounds, which is the figure for a body belt
C1,800 pounds on a body harness
DThere is no limit, provided the fall is arrested successfully

3

What does a gutter and downspout system need to be sized against?

AThe length of the eave being served, regardless of roof area
BThe slope of the roof surface above the gutter line
CThe roof area drained and the local design rainfall intensity
DThe height of the building above the finished grade

Worked explanations

The paper carries one for every question, at the back. These are the three above.

Q1 A Ch. 6: Mechanical and Plumbing Systems

Answer: A - When the water supply cannot meet the system's required pressure and flow

Because The system's hydraulic demand is compared against what the supply can actually deliver, established by a flow test. A pump is installed only where the supply falls short, and it is one of the more expensive components to add. NFPA 13 ch. 5

Where the other options lead

B.Ties it to system type. Dry systems have their own requirements, but a pump follows from the supply.
C.Makes it universal. Many buildings are served adequately by the street main.
D.Uses building height alone. Height increases static loss, but adequacy still depends on the available supply.

Q2 C Ch. 2: General Requirements

Answer: C - 1,800 pounds on a body harness

Because The system must limit the maximum arresting force on an employee to 1,800 pounds when a body harness is used. It must also bring the worker to a complete stop, limit the deceleration distance to 3.5 feet and be strong enough for twice the potential impact energy. 29 CFR 1926.502

Where the other options lead

A.Uses the anchorage figure. The anchorage must hold 5,000 pounds; the worker must not be subjected to it.
B.Uses the superseded body belt figure. Body belts have not been acceptable in a personal fall arrest system since 1998.
D.Removes the limit. A fall stopped too abruptly injures the worker as surely as the ground would.

Q3 C Ch. 8: Thermal and Moisture Protection

Answer: C - The roof area drained and the local design rainfall intensity

Because Capacity depends on how much water arrives, which is the tributary roof area multiplied by the rainfall rate for that location. Undersized systems overflow at the back of the gutter and soak the wall below. IPC ch. 11

Where the other options lead

A.Uses eave length. A long eave on a shallow roof drains less than a short eave on a large one.
B.Uses slope. Slope affects velocity but the volume is set by plan area.
D.Uses height. Height affects downspout routing rather than required capacity.

Worked explanations

The paper carries one for every question, at the back. These are the three above.

Q1 A Ch. 6: Mechanical and Plumbing Systems

Answer: A - When the water supply cannot meet the system's required pressure and flow

Because The system's hydraulic demand is compared against what the supply can actually deliver, established by a flow test. A pump is installed only where the supply falls short, and it is one of the more expensive components to add. NFPA 13 ch. 5

Where the other options lead

B.Ties it to system type. Dry systems have their own requirements, but a pump follows from the supply.
C.Makes it universal. Many buildings are served adequately by the street main.
D.Uses building height alone. Height increases static loss, but adequacy still depends on the available supply.

Q2 C Ch. 2: General Requirements

Answer: C - 1,800 pounds on a body harness

Because The system must limit the maximum arresting force on an employee to 1,800 pounds when a body harness is used. It must also bring the worker to a complete stop, limit the deceleration distance to 3.5 feet and be strong enough for twice the potential impact energy. 29 CFR 1926.502

Where the other options lead

A.Uses the anchorage figure. The anchorage must hold 5,000 pounds; the worker must not be subjected to it.
B.Uses the superseded body belt figure. Body belts have not been acceptable in a personal fall arrest system since 1998.
D.Removes the limit. A fall stopped too abruptly injures the worker as surely as the ground would.

Q3 C Ch. 8: Thermal and Moisture Protection

Answer: C - The roof area drained and the local design rainfall intensity

Because Capacity depends on how much water arrives, which is the tributary roof area multiplied by the rainfall rate for that location. Undersized systems overflow at the back of the gutter and soak the wall below. IPC ch. 11

Where the other options lead

A.Uses eave length. A long eave on a shallow roof drains less than a short eave on a large one.
B.Uses slope. Slope affects velocity but the volume is set by plan area.
D.Uses height. Height affects downspout routing rather than required capacity.

The rest of this mock paper comes with the course

NASCLA Commercial GB: the whole syllabus taught, the questions that test it, 5 timed mocks, and all 6 PDFs to print.