OBJ 3.3

Question 1

Intumescent

Answer 1

A coating or sealant that rapidly expands when exposed to heat such as from a fire. The swelling protects the underlying material by becoming less dense and acting as an insulator. One example is intumescent fire-retardant paint on structural steel.

Question 2

Define STC, NRC, and IIC.

Answer 2

STC refers to sound transmission class and it indicates a material or assembly's ability to block air-borne noise. The higher the STC, the better it blocks sound.
NRC is the noise reduction coefficient, which measures the amount of sound energy absorbed by a material. Materials are given values between 0 and 1, with 0 indicating perfect reflection and 1 indicating perfect absorption. IIC is the impact isolation class and represents a measurement of a floor and ceiling assembly's ability to attenuate impact noises such as footsteps. A larger IIC number means greater attenuation.

Question 3

Door Hardware Set

Answer 3

Typically specified in sets, door hardware packages include all latches, locks, hinges, door closers, panic devices, and other devices necessary for the door’s operation.

Question 4

Gypsum Wallboard Finish Level

Answer 4

Defines how visible joints are and how smooth the finish is for gypsum wallboard. Level 1 is the most rough in appearance, typically used in areas that are not in view (i.e., in a ceiling plenum). Level 5 is the highest end finish, which is used in applications that are to receive any specialty coating, such as unbacked vinyl graphics, specialty paints, or areas that may have harsh light. Level 4 is the commonly specified finish for areas that are to receive paint, or a wall covering.

Question 5

Spray Foam Insulation: Open Cell vs. Closed Cell

Answer 5

Open cell: lower R value (around 3–4 per inch) and impermeable to air but permeable to moistureClosed cell: higher R value (around 6 per inch) and impermeable to air and moisture

Question 6

Coal Tar Enamel

Answer 6

Coating for anticorrosion that is resistant to soil bacteria, marine organisms, and root growth; used in subterranean pipelines for petroleum products.

Question 7

Alkyd

Answer 7

A modern synthetic resin used to replace oil in varnishes, paints, and adhesives.

Question 8

Acrylic Paint

Answer 8

Fast-drying, water-resistant paint containing pigments suspended in acrylic polymer emulsion.

Question 9

Urethane Paint

Answer 9

A catalyst paint known for exceptional durability (long lasting).

Question 10

Oleoresinous Paint

Answer 10

Naturally occurring mixture of oil and a resin extracted from pine/fir trees and thinned with a solvent like turpentine.

Question 11

Bituminous Paint

Answer 11

A low-cost coating that contains asphalt or coal tar, a thinner, and drying oils that is used to waterproof concrete and to protect piping where bleeding of the asphalt is acceptable.

Question 12

Rigid Insulation

Answer 12

Approximate R-value per inch:
Polyisocyanurate (Polyiso): 5.7 to 6
Extruded Polystyrene (XPS): 5
Expanded Polystyrene (EPS): 3.6 to 4.2

Question 13

Hasp Lock

Answer 13

A metal fastener composed of a metal plate with a slot in it that fits over a u-shaped piece with a padlock or bolt that can be inserted in order to close and lock.

Question 14

Paint components

Answer 14

Pigment, binder, and solvent.

Question 15

Gypsum

Answer 15

A common mineral mined out of the Earth that is the main ingredient in plaster and drywall.

Question 16

Alabaster

Answer 16

Mineral that, when cut thin, can be used instead of glass in windows.

Question 17

Acoustic Ceiling Tile

Answer 17

Tiles coming in a variety of textures and sizes that can be suspended from the structure or glued to a horizontal ceiling surface. These tiles are typically fibrous, sound-absorbing material, such as mineral fiber, fiberglass, wood, cork, and perforated metal panel.

Question 18

Acoustic Ceiling Baffles

Answer 18

Acoustic baffles are ceiling-mounted, either vertically or horizontally oriented panels that absorb the reflected noise that bounces off hard flat walls, floors, and ceilings. A typical use of ceiling baffles is to orient them vertically and stack several in a row, which provides more surface area for sound absorption. Sound baffles are typically made of fabrics and are low in cost.

Question 19

True or false? Information about material quality and installation methods should be located in the drawings.

Answer 19

False. This information should be located in the specifications.

Question 20

In the event of a discrepancy between the drawings and the specifications, which prevails?

Answer 20

Specifications.

Question 21

True or false? The drawings show the configuration, size, and layout, and the specifications describe the quality and requirements for the execution of the work.

Answer 21

True.

Question 22

Coordinating specifications with drawings

Answer 22

• There should be a specification for every material shown on the drawings
• The same language should be used in both (e.g., don’t say “drywall” in the drawings and “gypsum board” in the specifications
• Avoid repeating information to reduce the possibility of errors (e.g., don’t call out the thickness of flashing in the specs if it is already in the drawings)