CSLB C-17 Glazing (Trade Exam) — All Questions
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260 questions
Which adhesive type does the mirror bulletin direct installers to use when adhesive is necessary?
- a.Any fast-curing adhesive
- b.Adhesive containing acetone
- c.Acid-cure adhesive
- d.Neutral-cure adhesive✓
The bulletin calls for neutral-cure adhesives. Adhesive containing acetone is a strong solvent that attacks mirror backings, acid-cure adhesive releases acetic acid that does the same, and a fast cure is not a criterion because some fast-curing products are acid-cure.GANA MD 03-0709 Mirror installation bulletin (2009)
What minimum space does the mirror bulletin say to leave under the bottom edge of a mirror?
- a.10 mm✓
- b.100 mm
- c.1 mm
- d.3 mm
The bulletin insists on at least 10 mm between the bottom edge of a mirror and other surfaces for drainage. Three millimeters and 1 mm trap moisture, and 100 mm is far more than the minimum the bulletin asks for.GANA MD 03-0709 Mirror installation bulletin (2009)
May mirrors be installed on a freshly painted wall?
- a.Yes, right away while the paint is wet
- b.Yes, if the mirror is taped to the wall
- c.Not until the paint is dry or sealed✓
- d.Yes, if the room is kept closed up tight
The bulletin says never to install mirrors on new plaster, new masonry or a freshly painted wall until dried or properly sealed, because airborne solvents attack the silver. Taping or closing the room does not help.GANA MD 03-0709 Mirror installation bulletin (2009)
A skylight on a store roof is set at an angle of 30 degrees from horizontal. How is it mounted under the Building Code?
- a.On a curb that is 1 inch high
- b.On a curb that is 12 inches high
- c.On a curb at least 4 inches high✓
- d.Flush with the roof plane, with no curb
Skylights at an angle less than 45 degrees from horizontal are mounted not less than 4 inches above the roof plane on a curb. Flush and 1-inch mounting are too low, and 12 inches is not the code figure.2025 CBC §2405.4
What are the mesh and distance limits for a broken-glass retention screen under sloped glazing?
- a.Mesh of 1/8 inch, within 1/2 inch of the glass
- b.Mesh of 3 inches, within 12 inches of the glass
- c.Mesh of 1 inch or less, within 4 inches of the glass✓
- d.Mesh of 2 inches, within 6 inches of the glass
The screen has mesh not larger than 1 by 1 inch, is installed within 4 inches of the glass and supports twice the weight of the glazing. The other pairs are not the code values.2025 CBC §2405.3
What interlayer thickness does the code require for monolithic laminated sloped glazing?
- a.A 5-mil polyvinyl butyral layer
- b.A 1/2-inch interlayer of clear plastic
- c.A minimum 30-mil polyvinyl butyral layer✓
- d.No interlayer, since the plies are tempered
Laminated monolithic sloped glazing has a minimum 30-mil PVB or equivalent interlayer. Five mils is too thin, an interlayer is required, and half an inch is not the figure.2025 CBC §2405.2
How many glass balusters must support the top rail of a guard with structural glass balusters?
- a.Only two balusters
- b.Not fewer than ten
- c.Only one baluster
- d.Not fewer than three✓
The top rail is supported by not fewer than three glass balusters, or otherwise supported to stay in place if one fails. One or two are not enough, and ten is not required.2025 CBC §2407.1.2
What glass is required for fire department access panels?
- a.Tempered glass✓
- b.Wired glass
- c.Annealed glass
- d.Heat-strengthened glass
Fire department glass access panels must be tempered, and in multipanel assemblies all panes are tempered. Annealed, heat-strengthened and wired glass do not qualify.2025 CBC §2406.5
What glass is required in elevator hoistway enclosures and hoistway doors?
- a.Annealed glass
- b.Patterned glass
- c.Laminated glass✓
- d.Wired glass
The code requires laminated glass meeting ANSI Z97.1 or CPSC 16 CFR 1201 in hoistway enclosures and doors. Annealed, patterned and wired glass do not qualify.2025 CBC §2409.2
At what height above the playing surface are impacts applied in racquetball court glass testing?
- a.59 inches✓
- b.12 inches
- c.24 inches
- d.96 inches
The code applies impacts at a height of 59 inches above the playing surface. Twelve and 24 inches are too low, and 96 inches is above a typical wall.2025 CBC §2408.2.1
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A joint is 5/8 inch wide. Which is the smallest listed backer rod diameter that is at least 25 percent larger?
- a.3/4 inch
- b.1/2 inch
- c.5/8 inch
- d.13/16 inch✓
The minimum is 0.625 × 1.25 = 0.78 inch, so 13/16 inch (0.8125) is the smallest listed that qualifies. A 5/8-inch rod equals the joint, 3/4 inch is only 20 percent larger, and 1/2 inch is smaller than the joint.UFGS 08 81 00
What does a closed-cell backer rod or bond breaker accomplish in a joint?
- a.Lets sealant bond to all three sides
- b.Takes the place of the sealant
- c.Makes the finished joint rigid
- d.Keeps sealant bonded on two sides✓
Backer rod or bond breaker ensures the sealant adheres to two sides of a three-sided joint so it can stretch. It does not make the joint rigid, three-sided adhesion is what it prevents, and it does not replace the sealant.NIH DRM News to Use, Sealant Joints Part 2 (2021)
A perimeter joint is 1 inch wide. What does the bulletin require?
- a.A larger backer rod only
- b.A deeper bead to span the wide joint
- c.A thinner bead of sealant across the joint
- d.A flashing to reduce the exposed width✓
Where joint width exceeds 3/4 inch, a flashing reduces the exposed width. A larger rod alone does not reduce the exposed width, a deeper bead makes the sealant work harder across the wider gap, and a thinner bead does not narrow the joint.NIH DRM News to Use, Sealant Joints Part 2 (2021)
A joint is 1/2 inch wide. Under the 2:1 ratio of joint width to backer rod setback, what is the setback?
- a.1/4 inch✓
- b.3/8 inch
- c.1/2 inch
- d.1 inch
A 2:1 ratio gives a setback of 1/4 inch. A 1/2-inch setback is a 1:1 ratio, 1 inch is a 1:2 ratio, and 3/8 inch is the maximum, not the 2:1 result.NIH DRM News to Use, Sealant Joints Part 2 (2021)
How is a finished sealant surface shaped?
- a.Tooled flush to slightly concave✓
- b.Built up into a dome above the joint
- c.Scored down the middle with a knife
- d.Left rough, as it came off the gun
The bulletin says to tool flush to slightly concave for a smooth continuous joint. Rough, domed and scored surfaces trap water and weaken adhesion.NIH DRM News to Use, Sealant Joints Part 2 (2021)
Which joint condition does the bulletin say to avoid in design and detailing?
- a.Coplanar gapped joints with closed-cell backer rod
- b.Joints with a flashing at wide gaps
- c.Joints that are tooled to a concave shape
- d.Coplanar abutting joints✓
Coplanar abutting joints leave inadequate room for a sealant joint and should be avoided. The other conditions are recommended practice.NIH DRM News to Use, Sealant Joints Part 2 (2021)
In what condition must glass be when the federal guide specification says work is accepted?
- a.Covered with protective film
- b.Dirty but intact
- c.Labeled with all construction labels
- d.Clean✓
The specification says glass must be clean at the time the work is accepted, with labels, paint spots and putty removed. Dirty, film-covered or fully labeled glass is not accepted.UFGS 08 81 00
How should protective material be placed over reflective glass?
- a.Spaced off the coating so air can move✓
- b.Glued directly to the coated glass surface
- c.Taped tightly against the coated surface
- d.Left off because glass needs no protection
The specification calls for protective material far enough from the coated glass to allow air to circulate. Tight tape and glue contaminate the coating, and protection is required.UFGS 08 81 00
A lite is chipped during construction. What does the guide specification require?
- a.Replace it with a new unit✓
- b.Polish the chip
- c.Leave it if the chip is small
- d.Fill the chip with sealant
The specification requires removing and replacing glass units that are broken, chipped, cracked, abraded or otherwise damaged during construction. Polishing leaves the damaged unit in place, filling the chip with sealant hides the break origin, and leaving a small chip ignores that chipped glass is on the list.UFGS 08 81 00
What is used to mark glazed openings after installation under the guide specification?
- a.Permanent paint rolled across the glass
- b.Dust and marks left on the glass from the work
- c.Tape or flags attached with non-staining adhesive✓
- d.A sign posted at the door of the building
The specification calls for warning tapes or flags attached with non-staining adhesives. Permanent paint damages the glass, a sign at the building door does not mark the openings themselves, and leftover dust is neither a deliberate marking nor easy to remove.UFGS 08 81 00
Why is glass near welding protected?
- a.Welding adds weight to the lite
- b.Sparks can damage the glass surface✓
- c.Welding seals the glass edges shut
- d.Welding changes the color of the glass
Sparks from welding are a cause of surface damage and degradation. The other effects are not described.Pilkington ATS-192 General glazing guidelines (2013)
What should be done with movable sash and doors until glazing compound has set?
- a.Operate them often to test the fit of the hardware
- b.Remove them from the building until later
- c.Fix them or keep them closed and locked✓
- d.Leave them open for good airflow
The specification says to fix movable items or keep them closed and locked until the compound has thoroughly set. Opening, cycling and removal disturb the compound.UFGS 08 81 00
A broken infill lite in an old balcony guard is replaced. What must the new glass be?
- a.Laminated glass, 1/4 inch or thicker, of treated plies✓
- b.Wired glass to match the look of the railing design
- c.Annealed glass of the same type as the old lite
- d.Single heat-strengthened glass in the same thickness
Replacement is held to new-work rules, and glass in guards must be laminated, 1/4 inch nominal or more, made of tempered or heat-strengthened glass. Annealed glass, single heat-strengthened glass and wired glass do not meet that rule.2025 CBC §2402.1, §2407.1
A fixed lite 20 inches from a door's edge has its bottom edge 40 inches above the floor in a store and must be replaced. What is installed?
- a.Annealed glass
- b.Heat-strengthened glass
- c.Identified safety glazing✓
- d.Plain laminated glass with no identification
The location is hazardous under the Building Code, and replacement glass is installed as for new work, so identified safety glazing is required. Annealed and heat-strengthened glass are not safety glazing, and safety glazing must be identified.2025 CBC §2402.1, §2406.4.2
A pane in a bathtub enclosure breaks. What category must the replacement meet?
- a.Category I
- b.No category
- c.Category III
- d.Category II✓
Bathtub doors and enclosures are Category II under the federal standard, and replacement follows new-work rules. Category I covers doors of 9 square feet or less, a category does apply, and there is no Category III.16 CFR 1201.2; 2025 CBC §2402.1
Which materials may replace a monolithic sloped lite in a skylight under the Building Code?
- a.Single-strength sheet glass that is set in a sloped sash
- b.Annealed glass of any thickness that fits the opening
- c.Laminated with 30-mil PVB, heat-strengthened or fully tempered glass✓
- d.Patterned annealed glass of any thickness that fits
Sloped glazing is limited to materials such as laminated glass with a minimum 30-mil PVB interlayer, heat-strengthened or fully tempered glass, subject to screens. Annealed, patterned annealed and sheet glass are not listed for monolithic sloped use.2025 CBC §2405.2
A broken lite in a fire-rated wall window is replaced. What is correct?
- a.Clear annealed glass, if it fits the opening
- b.Any tempered glass of the same size, since tempering adds strength
- c.Labeled rated glazing, same or higher rating, in a labeled frame✓
- d.No glass, leaving the opening empty for now
Rated assemblies are replaced with labeled glazing of at least the required rating, installed as the label requires. Plain or tempered glass has no rating, and an empty opening defeats the wall.2025 CBC §716.1.2.2
A mirror is to be replaced on a freshly painted wall. What does the bulletin say?
- a.Wait until the paint is dry or the wall is sealed✓
- b.Use an acid-cure adhesive for a faster set
- c.Install it right away to save a second trip
- d.Seal the mirror edges with paint to protect them from moisture
Mirrors are not installed on freshly painted walls until dried or sealed, because solvents attack the silver backing. Painted edges and acid-cure adhesives also harm the mirror.GANA MD 03-0709 Mirror installation bulletin (2009)
How should the opening for a replacement lite be measured?
- a.By adding 1/2 inch to the size of the frame
- b.By measuring the actual opening to receive the glass✓
- c.By reading the dimensions from the original drawing
- d.By using the size of the broken glass as it was
The specification says to determine sizes by measuring the actual opening. The drawing, the old size and a flat allowance ignore real variation and frame movement.UFGS 08 81 00
An insulating unit has two 3/16-inch lites and a 1/2-inch air space. What is its overall thickness?
- a.3/8 inch
- b.7/8 inch✓
- c.1-3/16 inches
- d.1/2 inch
Overall thickness is outside surface to outside surface: 3/16 + 1/2 + 3/16 = 7/8 inch. The 1/2 inch is the gap only, 3/8 inch is the glass alone, and 1-3/16 adds an extra lite.2025 Energy Code residential compliance manual, Ch. 3
An insulating unit has two 1/4-inch lites and an overall thickness of 1 inch. What is the gap width?
- a.3/4 inch
- b.1 inch
- c.1/2 inch✓
- d.1/4 inch
The gap is measured inside surface to inside surface: 1 − 1/4 − 1/4 = 1/2 inch. One inch is the overall thickness, and 3/4 and 1/4 inch do not match the arithmetic.2025 Energy Code residential compliance manual, Ch. 3
How is identification applied to tempered glass?
- a.By a removable paper label applied to all tempered glass
- b.Permanently, by etching, firing, embossing or the like✓
- c.By a sticker that can be taken off and reapplied
- d.By a pencil mark made on the corner of the lite
Each pane of tempered glass, except spandrel glass, is permanently identified by the manufacturer by acid etching, sandblasting, ceramic firing, laser etching or embossing. A removable label, pencil mark or reusable sticker can be removed without destroying it.2025 CBC §2403.1
An annealed lite cracks where the upper half sits in the shade of a canopy and the lower half is in sun. What is the likely cause?
- a.Spontaneous breakage of a tempered lite
- b.Thermal stress from uneven heating of the lite✓
- c.A failed edge seal in the insulating glass unit
- d.Normal wear that comes with old glass
Deep shadows reduce solar heating in part of a lite and are a named cause of thermal stress breakage in annealed glass. Spontaneous breakage involves tempered glass, a failed seal shows as fogging, and wear is not a described cause.Pilkington ATS-192 General glazing guidelines (2013)
A supply duct blows hot air directly on a lite that has cracked twice. What is the likely cause?
- a.Setting blocks that were cut too long for the lite
- b.Thermal stress from misdirected HVAC airflow✓
- c.A sealant that was the wrong color for the frame
- d.A pocket that was cut too tight for the lite
Ducts that blow directly against glass cause thermal stress during heating and cooling cycles. A tight pocket or long setting blocks can break glass, but neither follows the airflow that the stem points to, and a sealant of the wrong color has no effect on glass stress at all.Pilkington ATS-192 General glazing guidelines (2013)
Why can a small chip at an edge hidden in the pocket cause a later break?
- a.It changes the color of the glass at the edge
- b.It reduces the bite of the glass edge in the pocket
- c.It makes the whole lite noticeably heavier in the frame
- d.It can become a break origin under normal stress✓
Chips and impacts at the edge can be initially hidden in the glazing channel and later become break origins. A chip does not add weight, change the bite or change color.Pilkington ATS-192 General glazing guidelines (2013)
Which glass type has the known possibility of spontaneous breakage?
- a.Annealed glass
- b.Laminated annealed glass
- c.Fully tempered glass✓
- d.Plastic glazing
The industry paper lists the possibility of spontaneous breakage as a drawback of fully tempered glass. Annealed, laminated annealed and plastic glazing are not described that way.GANA FB45-14 Recommended Applications for Heat-Treated Glass (2019)
What does fogging between the panes of an insulating unit show?
- a.The coating has been applied to the wrong face
- b.The lite was heat-treated before it was sealed
- c.Moisture has entered through a failed seal✓
- d.The air space is too wide
Fogging is the visible sign of seal failure when moisture overwhelms the desiccant. Tempering does not put moisture in the air space, a wide air space is a design choice and does not fog, and a coating on the wrong face changes performance, not clarity between panes.Guardian Glass IGU Expert Series brochure (2020)
What condition in the pocket is a primary cause of seal failure in insulating units?
- a.Ponding of water✓
- b.Dry air
- c.Open weeps
- d.Clean setting blocks
Poorly placed blocks or blocked weeps can cause ponding of water, a primary cause of seal failure. Dry air, clean blocks and open weeps prevent it.Pilkington ATS-192 General glazing guidelines (2013)
Which personal protection does Title 8 point to when removing broken glass?
- a.Hearing protection and a hard hat
- b.Eye protection and hand protection✓
- c.A respirator and a rubber apron
- d.A safety harness and a lanyard
Title 8 requires eye and face protection where flying particles risk eye injury and hand protection where cuts are likely, and broken glass creates both hazards. Hearing protection and a hard hat answer noise and overhead impact, a respirator and apron answer vapors and splashes, and a harness answers a fall, none of which is the main exposure when handling broken glass.Title 8 §3382, §3384
When may debris be thrown from a building to the area below?
- a.Whenever the pieces are small and light
- b.Onto a public sidewalk, if the walk is clear
- c.Only into a guarded and posted fall zone✓
- d.When a worker calls out a warning first
Title 8 allows it only where the area is guarded by fences, barricades or other means and signs are posted. A clear public sidewalk is not a guarded zone, small pieces still injure people below, and a shouted warning is not a barrier or a sign.Title 8 §1513(g)
A firm will remove painted wood windows in a house built before 1978 and disturb more than the minor-repair amount. What does the federal rule require?
- a.A verbal notice given to the owner
- b.An EPA-certified firm that follows the work practices✓
- c.Nothing, since window removal is not covered by the rule
- d.A permit issued by the glass supplier
Removing building components such as windows is renovation when painted surfaces are disturbed, and firms in target housing must be certified and follow the work practices. The rule does cover window removal, a glass supplier has no permitting role under it, and a verbal notice does not replace certification and the work practices.40 CFR 745.81, 745.82
What is the largest disturbance of painted surface inside per room that is treated as minor repair and maintenance under the renovation rule?
- a.6 square feet or less per room✓
- b.1 square foot or less per room
- c.20 square feet or less per room
- d.60 square feet or less per room
Interior activities that disrupt 6 square feet or less of painted surface per room are minor repair, subject to conditions. Sixty and 1 are not the thresholds, and 20 square feet is the exterior figure.40 CFR 745.83
Title 8 regulates asbestos exposure in which work?
- a.Only in painting
- b.Only in demolition
- c.Only in new construction
- d.In all construction work✓
Section 1529 regulates asbestos exposure in all construction work. It is not limited to demolition, new work or painting.Title 8 §1529
Why is the coating position of a failed insulating unit confirmed before the replacement is ordered?
- a.The coating position sets the weight of the unit
- b.The coating position controls the depth of the pocket
- c.The coating is applied on site after the unit is set
- d.A coating on the wrong surface cannot be fixed later✓
Surfaces are numbered from the outside, and the coating belongs on the surface the drawings or the old unit show, so the order must state it; a coating on the wrong surface cannot be corrected after installation. The coating does not set weight, it is applied at the factory, and it does not set pocket depth.Guardian Glass IGU brochure; 2025 Energy Code residential compliance manual Ch. 3
A manufacturer's face clearance is 1/8 inch on each side. What pocket width is needed for a 1/4-inch monolithic lite?
- a.3/8 inch
- b.1/2 inch✓
- c.1/4 inch
- d.5/8 inch
The pocket needs the lite's thickness plus a face clearance on each side, 1/4 + 2 × 1/8 = 1/2 inch. A 1/4-inch pocket leaves no clearance, 3/8 counts one side, and 5/8 is more than required.Pilkington ATS-192; Viracon Glazing Guidelines
A laminated lite is made of two 1/4-inch plies and the manufacturer's face clearance is 1/8 inch per side. What pocket width is needed?
- a.1 inch
- b.3/4 inch✓
- c.5/8 inch
- d.1/2 inch
The lite is 1/2 inch thick, so the pocket is 1/2 + 2 × 1/8 = 3/4 inch. A 1/2-inch pocket has no clearance, 5/8 counts one side, and 1 inch is more than required.Viracon Glazing Guidelines - Standard
A 3-by-5-foot lite of 1/4-inch glass is replaced by a unit with two 1/4-inch lites. How many more pounds does the frame carry?
- a.About 97 pounds
- b.About 49 pounds✓
- c.About 0 pounds
- d.About 24 pounds
The old lite weighs 13 × 0.25 × 15 = 48.75 pounds and the new unit 97.5, an increase of 48.75 pounds. The 97 is the new weight, 24 halves the increase, and the second lite adds weight.2025 CBC §2404.2
A 4-by-8-foot lite of 1/8-inch glass is replaced by laminated glass of two 1/4-inch plies. How many more pounds does the frame carry?
- a.About 104 pounds
- b.About 208 pounds
- c.About 52 pounds
- d.About 156 pounds✓
The old lite is 13 × 0.125 × 32 = 52 pounds and the new lite 13 × 0.5 × 32 = 208 pounds, an increase of 156 pounds. The 208 is the new weight, 52 is the old, and 104 halves the increase.2025 CBC §2404.2
Two windows total 80 square feet: 30 square feet at U = 0.25 and 50 square feet at U = 0.35. What is the area-weighted U-factor?
- a.About 0.31✓
- b.About 0.35
- c.About 0.30
- d.About 0.25
(0.25 × 30 + 0.35 × 50) ÷ 80 = 25 ÷ 80 = 0.3125. The simple average is 0.30, and 0.35 and 0.25 ignore the other window.2025 Energy Code residential compliance manual, Ch. 3
Windows of 20 square feet at U = 0.50 and 20 square feet at U = 0.30 are installed. What is the area-weighted U-factor?
- a.0.40✓
- b.0.30
- c.0.20
- d.0.50
With equal areas the average is (0.50 + 0.30) ÷ 2 = 0.40. The 0.50 and 0.30 ignore one window, and 0.20 is the difference.2025 Energy Code residential compliance manual, Ch. 3