GCC Materials & Equipment Knowledge 2

Question 1

What is the minimum compressive strength of concrete typically specified for residential foundation footings?

Accepted Answer

3,000 psi

Answer

3,000 psi is the standard minimum compressive strength specified for residential foundation concrete per most building codes.

Question 2

Which type of lumber grading system is used for structural applications in the US?

Accepted Answer

Visual and machine stress-rated (MSR) grading

Answer

Visual and machine stress-rated (MSR) grading systems are used to classify lumber for structural applications based on strength properties.

Question 3

What does the R-value of insulation measure?

Accepted Answer

Thermal resistance to heat flow

Answer

R-value measures the thermal resistance of insulation material — the higher the R-value, the greater the resistance to heat flow.

Question 4

A contractor needs to select rebar for a concrete beam. Grade 60 rebar has a minimum yield strength of:

Accepted Answer

60,000 psi

Answer

Grade 60 rebar has a minimum yield strength of 60,000 psi, which is the most commonly used grade in structural concrete.

Question 5

What is the primary advantage of using engineered lumber (LVL) over dimensional lumber for long-span beams?

Accepted Answer

Greater dimensional stability and higher strength-to-weight ratio

Answer

LVL (Laminated Veneer Lumber) offers greater dimensional stability and a higher strength-to-weight ratio compared to sawn lumber, making it ideal for long spans.

(GCC) General Contracting Certification Practice Test

(GCC) General Contracting Certification Practice Test

GCC Materials & Equipment Knowledge 2