CSLB C-17 Glazing (Trade Exam) — All Questions
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39 questions
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
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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
A door of 12 square feet has 3 square feet of glass. How does the Energy Code treat it?
- a.An opaque door, since glass is only a small share
- b.Exempt from the glazing rules in the code
- c.A skylight, since it is in an exterior wall
- d.Fenestration, since glass is 25 percent of the door✓
3 ÷ 12 is exactly 25 percent, and glass area greater than or equal to 25 percent makes the door a fenestration product. An opaque door has under 25 percent, and the door is not a skylight or exempt.2025 Energy Code residential compliance manual, Ch. 3
A door of 24 square feet has 2 square feet of glass. How is it treated?
- a.As a window
- b.As an opaque exterior door✓
- c.As a fenestration product
- d.As a glazed door needing NFRC glass values
2 ÷ 24 is 8.3 percent, which is under 25 percent, so the door is treated as opaque. It is not fenestration, does not need glass values and is not a window.2025 Energy Code residential compliance manual, Ch. 3
A new window is not field-fabricated. What label must it carry?
- a.A tint label stating the color of the glass tint
- b.A wind rating label that gives the design pressure
- c.An NFRC-certified or default-efficiency label✓
- d.An installer sticker that gives the crew's name
Windows that are not field-fabricated must be labeled with NFRC-certified or default efficiencies. A tint, installer or wind rating label does not state U-factor and SHGC.2025 Energy Code residential compliance manual, Ch. 3
Where do field-fabricated windows get their U-factor and SHGC for compliance?
- a.From the previous window
- b.From the installer's estimate
- c.From the glass supplier's brochure
- d.From the Energy Code default tables✓
Field-fabricated windows use the default tables of the Energy Code. A brochure, an estimate or the old window's value is not an accepted source.2025 Energy Code residential compliance manual, Ch. 3
Which label is applied for the building inspector's review of default values?
- a.A temporary label✓
- b.A sales invoice
- c.A permanent engraving
- d.An insurance certificate
Temporary labels carrying the compliance values are applied for the inspector. A permanent engraving, an insurance certificate and an invoice are not the review label.2025 Energy Code residential compliance manual, Ch. 3
Why must the glass manufacturer be consulted before adding film to an annealed lite?
- a.Film moves the setting blocks out of position
- b.Film makes the frame heavier on the wall
- c.Film changes solar absorption and thermal stress✓
- d.Film makes the glass thinner in the frame
Film changes how the lite absorbs solar energy, and annealed glass can break from thermal stress. The frame weight added by film is negligible, film does not thin the glass, and it does not move the setting blocks.CEC manual (window film); Pilkington ATS-192
What benefit does laminated glass add in a retrofit besides safety glazing performance?
- a.Elimination of the need for a frame
- b.Lower weight than annealed glass
- c.Greater optical distortion removal
- d.Reduced sound transmission✓
The industry paper lists reduced sound transmission as a benefit of laminated glass. It does not remove distortion, eliminate the frame or weigh less than annealed glass of the same thickness.GANA FB45-14 Recommended Applications for Heat-Treated Glass (2019)
In a dwelling, an operable window has its clear opening 18 inches above the floor and 40 feet above grade. What does the Residential Code require?
- a.A larger sash so the window can open wider
- b.A screen fixed over the full window opening
- c.A 4-inch sphere limit or a control device✓
- d.A guard placed in front of the glass only
Windows with a sill under 24 inches above the floor and more than 72 inches above grade must stop a 4-inch sphere or have a window opening control device. A guard in front of the glass is not the listed solution, a larger sash opens wider and makes the fall hazard worse, and a screen does not stop a child from falling through.2025 CRC §R321.2.1
A window opening control device is installed on an emergency escape window. What must hold after the device is released?
- a.The window must be fixed in place so it cannot open
- b.The device must hold the sash half open at all times
- c.The device must stay locked until it is reset with a key
- d.The net clear opening must still meet the required area✓
After release the device must not reduce the net clear opening area of the unit below the area required for escape. A sash held half open, a device that stays locked until a key resets it, and a sash fixed in place each defeat escape.2025 CRC §R321.2.2
What is the maximum prescriptive fenestration U-factor for climate zone 3 in the Energy Commission's manual?
- a.0.40
- b.0.10
- c.0.27✓
- d.0.50
The manual gives 0.27 for climate zones 1 through 5, 11 through 14 and 16, and 0.30 for the others. The 0.40 figure is the mandatory area-weighted limit, and 0.50 and 0.10 are not stated.2025 Energy Code residential compliance manual, Ch. 3
A retrofit replaces single glass with a thicker insulating unit. What must be checked about the existing frame?
- a.Pocket depth and the frame's capacity for the added weight✓
- b.The brand of the sealant that was used on the old glass
- c.The color of the frame and the glazing stops
- d.Nothing, since every pocket accepts every unit
A thicker unit needs a deeper pocket and the frame carries more weight, so both are checked. Color and sealant brand do not decide fit, and pockets are not universal.Pilkington ATS-192; Viracon Glazing Guidelines; 2025 CBC §2404.2