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Practice and exam technique

Practice: concrete and masonry

Compiled by the Sitonce editorial team from the PSI Candidate Information Bulletin, NASCLA's own published material and the federal standards named belowUpdated 2 min readFacts verified 4 September 2026
The short answer

Concrete carries 9 questions and Masonry 3, so 12 of 125 between them. Both are heavily lookup-based and the questions reward a tabbed reference more than memorization.

Twelve questions between the two categories, and most of them findable.

Four questions

Question 1

A slab on grade is specified at 4 inches thick, 30 feet by 40 feet. How much concrete is required, ignoring waste?

  1. 12.3 cubic yards
  2. 14.8 cubic yards
  3. 20 cubic yards
  4. 44.4 cubic yards
Answer: B. Thirty by forty is 1,200 square feet. Four inches is one third of a foot, giving 400 cubic feet. Divided by 27 that is 14.8 cubic yards. The most common error is failing to convert inches to feet, and the second is forgetting the 27.
Question 2

What is the primary purpose of a control joint in a concrete slab?

  1. To allow structural movement between building sections
  2. To create a weakened plane so shrinkage cracking occurs where intended
  3. To separate the slab from adjacent construction
  4. To provide a stopping point for a pour
Answer: B. A control joint creates a deliberate weakened plane. Concrete shrinks and will crack; the joint decides where. Option A describes an expansion joint and option C an isolation joint, and confusing the three is the standard trap in this category.
Question 3

Concrete placed in hot weather is most at risk from which of the following?

  1. Delayed set and low early strength
  2. Rapid moisture loss leading to plastic shrinkage cracking
  3. Freezing of mix water
  4. Excessive air entrainment
Answer: B. Heat and wind drive evaporation faster than bleed water can reach the surface, and the surface cracks while the concrete is still plastic. Option A and option C describe cold weather problems.
Question 4

A masonry wall is being laid in running bond. What does that describe?

  1. The mortar type
  2. The pattern in which units overlap, typically by half a unit
  3. The reinforcement spacing
  4. The method of tooling the joints
Answer: B. Running bond is a pattern of overlap, conventionally half a unit, giving the wall its structural interlock. Mortar type, reinforcement and joint tooling are all separate specifications.
The joint question comes up in some form

Control, expansion and isolation joints do three different things and the names get used loosely on site. Tab the definitions rather than trusting field usage.

What to have tabbed

  • Cubic yard conversion and volume worked examples
  • Joint definitions and typical spacing
  • Cover requirements for reinforcement
  • Hot and cold weather placement provisions
  • Mortar types and where each is used

Common questions

How many concrete and masonry questions are on the NASCLA exam?

Nine on Concrete and three on Masonry, so 12 of 125.

How do I calculate slab concrete?

Area in square feet times thickness in feet, divided by 27 for cubic yards.

What does a control joint do?

Creates a weakened plane so shrinkage cracking happens where intended.

What is the hot weather concrete risk?

Rapid moisture loss causing plastic shrinkage cracking.

What is running bond?

A pattern where units overlap, conventionally by half a unit.

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