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NEW YORK PLASTERER LICENSE EXAMINATION 2026
COMPLETE (105) CURRENT TESTING QUESTIONS AND
CORRECT ANSWERS WITH DETAILED RATIONALES.
PLASTERER
Prepare for the New York Plasterer License Examination with this comprehensive
study resource designed to reinforce essential plastering techniques, surface
preparation, material application, construction safety, building codes, and industry
best practices. This document helps you review key topics, assess your
understanding, and identify areas that may require additional study before the
licensing exam. Use it to strengthen your technical knowledge and build confidence
through focused, organized preparation. An excellent companion for successful New
York Plasterer License exam preparation.
MULTIPLE CHOICE.
Work Preparation, Layout & Surface Preparation (Questions 1–20)
Question 1: What is the first step in preparing an old painted wall for
plastering?
A. Apply a bonding agent directly over the paint
B. Remove or heavily score the paint to create a mechanical key
C. Seal the surface with oil-based primer
D. Install a layer of polyethylene sheeting
Correct answer: B. Remove or heavily score the paint to create a
mechanical key
Rationale: Paint prevents mechanical keying; removal or heavy scoring is
required under NYC codes to ensure proper plaster adhesion .
Question 2: Before applying plaster to a masonry wall, why is it important to
dampen the surface?
A. To speed up the drying process
B. To prevent the substrate from drawing water out of the new plaster too
quickly
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C. To improve the color of the finish coat
D. To reduce the need for a bonding agent
Correct answer: B. To prevent the substrate from drawing water out of the
new plaster too quickly
Rationale: Damping prevents rapid water absorption from the plaster,
which can cause cracking and poor adhesion .
Question 3: What is the primary purpose of lath in plaster work?
A. Improve fire resistance
B. Provide a mechanical key for plaster adhesion
C. Reduce drying time
D. Increase surface smoothness
Correct answer: B. Provide a mechanical key for plaster adhesion
Rationale: Lath creates a mechanical bond that allows plaster to grip and
adhere securely to the substrate .
Question 4: Which type of lath is most commonly used for exterior cement
plaster (stucco) in NYC?
A. Wood lath
B. Expanded metal lath
C. Gypsum lath
D. Fiberboard lath
Correct answer: B. Expanded metal lath
Rationale: Expanded metal lath is non-combustible and provides superior
keying for cementitious exterior plaster applications .
Question 5: What does "furring" refer to in plaster preparation?
A. Adding sand to lime plaster
B. Attaching strips to a wall to create an air gap or level surface
C. Mixing plaster with accelerators
D. Cleaning tools after use
Correct answer: B. Attaching strips to a wall to create an air gap or level
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surface
Rationale: Furring strips (wood or metal) are fastened to masonry to
provide a nailing base and separation from moisture .
Question 6: When preparing a surface for plastering, which factor is most
critical for ensuring adhesion?
A. Surface color
B. Surface cleanliness
C. Surface shape
D. Surface temperature
Correct answer: B. Surface cleanliness
Rationale: Clean surfaces ensure proper plaster adhesion; dirt, grease, or
loose material will prevent bonding .
Question 7: What is the correct technique for applying gypsum plaster to a
masonry wall to ensure proper bonding?
A. Apply bonding agent only
B. Apply the scratch coat first as the base layer
C. Apply the finish coat directly
D. Apply a sand coat first
Correct answer: B. Apply the scratch coat first as the base layer
Rationale: The scratch coat is the first base coat applied to provide a
rough key for subsequent plaster layers .
Question 8: In a three-coat plaster system over metal lath, what is the
minimum total thickness required by NYC building codes?
A. 1/4 inch
B. 1/2 inch
C. 3/4 inch
D. 7/8 inch
Correct answer: D. 7/8 inch
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Rationale: NYC building codes often reference 7/8 inch total thickness for
three-coat work over metal lath to ensure strength and fire resistance .
Question 9: Why should a scratch coat be scored with grooves?
A. To improve surface decoration
B. To increase plaster thickness
C. To provide a mechanical bond for the next coat
D. To reduce curing time
Correct answer: C. To provide a mechanical bond for the next coat
Rationale: Grooves in the scratch coat create mechanical bonding
surfaces for the brown coat .
Question 10: What is the standard approximate thickness of a plaster coat on
interior walls in traditional multi-coat systems?
A. 1/16 inch
B. 1/4 inch
C. 3/8 inch
D. 1 inch
Correct answer: C. 3/8 inch
Rationale: Traditional three-coat plaster systems typically total about 3/8
inch thick, including scratch coat, brown coat, and finish coat .
Question 11: What is the primary role of bonding agents in plastering?
A. Improve color
B. Speed drying
C. Improve adhesion to existing surfaces
D. Reduce cost
Correct answer: C. Improve adhesion to existing surfaces
Rationale: Bonding agents help plaster adhere to existing surfaces where
natural keying is insufficient .
NEW YORK PLASTERER LICENSE EXAMINATION 2026
COMPLETE (105) CURRENT TESTING QUESTIONS AND
CORRECT ANSWERS WITH DETAILED RATIONALES.
PLASTERER
Prepare for the New York Plasterer License Examination with this comprehensive
study resource designed to reinforce essential plastering techniques, surface
preparation, material application, construction safety, building codes, and industry
best practices. This document helps you review key topics, assess your
understanding, and identify areas that may require additional study before the
licensing exam. Use it to strengthen your technical knowledge and build confidence
through focused, organized preparation. An excellent companion for successful New
York Plasterer License exam preparation.
MULTIPLE CHOICE.
Work Preparation, Layout & Surface Preparation (Questions 1–20)
Question 1: What is the first step in preparing an old painted wall for
plastering?
A. Apply a bonding agent directly over the paint
B. Remove or heavily score the paint to create a mechanical key
C. Seal the surface with oil-based primer
D. Install a layer of polyethylene sheeting
Correct answer: B. Remove or heavily score the paint to create a
mechanical key
Rationale: Paint prevents mechanical keying; removal or heavy scoring is
required under NYC codes to ensure proper plaster adhesion .
Question 2: Before applying plaster to a masonry wall, why is it important to
dampen the surface?
A. To speed up the drying process
B. To prevent the substrate from drawing water out of the new plaster too
quickly
, Page 2 of 34
C. To improve the color of the finish coat
D. To reduce the need for a bonding agent
Correct answer: B. To prevent the substrate from drawing water out of the
new plaster too quickly
Rationale: Damping prevents rapid water absorption from the plaster,
which can cause cracking and poor adhesion .
Question 3: What is the primary purpose of lath in plaster work?
A. Improve fire resistance
B. Provide a mechanical key for plaster adhesion
C. Reduce drying time
D. Increase surface smoothness
Correct answer: B. Provide a mechanical key for plaster adhesion
Rationale: Lath creates a mechanical bond that allows plaster to grip and
adhere securely to the substrate .
Question 4: Which type of lath is most commonly used for exterior cement
plaster (stucco) in NYC?
A. Wood lath
B. Expanded metal lath
C. Gypsum lath
D. Fiberboard lath
Correct answer: B. Expanded metal lath
Rationale: Expanded metal lath is non-combustible and provides superior
keying for cementitious exterior plaster applications .
Question 5: What does "furring" refer to in plaster preparation?
A. Adding sand to lime plaster
B. Attaching strips to a wall to create an air gap or level surface
C. Mixing plaster with accelerators
D. Cleaning tools after use
Correct answer: B. Attaching strips to a wall to create an air gap or level
, Page 3 of 34
surface
Rationale: Furring strips (wood or metal) are fastened to masonry to
provide a nailing base and separation from moisture .
Question 6: When preparing a surface for plastering, which factor is most
critical for ensuring adhesion?
A. Surface color
B. Surface cleanliness
C. Surface shape
D. Surface temperature
Correct answer: B. Surface cleanliness
Rationale: Clean surfaces ensure proper plaster adhesion; dirt, grease, or
loose material will prevent bonding .
Question 7: What is the correct technique for applying gypsum plaster to a
masonry wall to ensure proper bonding?
A. Apply bonding agent only
B. Apply the scratch coat first as the base layer
C. Apply the finish coat directly
D. Apply a sand coat first
Correct answer: B. Apply the scratch coat first as the base layer
Rationale: The scratch coat is the first base coat applied to provide a
rough key for subsequent plaster layers .
Question 8: In a three-coat plaster system over metal lath, what is the
minimum total thickness required by NYC building codes?
A. 1/4 inch
B. 1/2 inch
C. 3/4 inch
D. 7/8 inch
Correct answer: D. 7/8 inch
, Page 4 of 34
Rationale: NYC building codes often reference 7/8 inch total thickness for
three-coat work over metal lath to ensure strength and fire resistance .
Question 9: Why should a scratch coat be scored with grooves?
A. To improve surface decoration
B. To increase plaster thickness
C. To provide a mechanical bond for the next coat
D. To reduce curing time
Correct answer: C. To provide a mechanical bond for the next coat
Rationale: Grooves in the scratch coat create mechanical bonding
surfaces for the brown coat .
Question 10: What is the standard approximate thickness of a plaster coat on
interior walls in traditional multi-coat systems?
A. 1/16 inch
B. 1/4 inch
C. 3/8 inch
D. 1 inch
Correct answer: C. 3/8 inch
Rationale: Traditional three-coat plaster systems typically total about 3/8
inch thick, including scratch coat, brown coat, and finish coat .
Question 11: What is the primary role of bonding agents in plastering?
A. Improve color
B. Speed drying
C. Improve adhesion to existing surfaces
D. Reduce cost
Correct answer: C. Improve adhesion to existing surfaces
Rationale: Bonding agents help plaster adhere to existing surfaces where
natural keying is insufficient .
