CSLB C-17 Glazing (Trade Exam) — All Questions
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55 questions
Top, middle and bottom width readings of an opening are 35-7/8, 36 and 36-1/8 inches. Which width is used to size the frame?
- a.36 inches
- b.35-7/8 inches✓
- c.36-1/8 inches
- d.36-1/16 inches
The smallest reading controls because the frame must fit the tightest point. The 36 inches is the middle reading and would bind at the narrow top, 36-1/8 is the widest reading and binds worse, and 36-1/16 is a figure between them that still exceeds the narrowest reading by 3/16 inch.UFGS 08 41 13 (verify openings); CSLB C-17 study guide 13E-17
Which measurement shows whether an opening is square?
- a.The width of the opening taken at the middle
- b.The height of the opening taken at one jamb
- c.The length of the sill measured end to end
- d.Both diagonals, measured corner to corner✓
Equal diagonals mean the opening is square, and the guideline allows a 1/8-inch difference. A single width, the sill length or one jamb height says nothing about squareness.Pilkington ATS-192 General glazing guidelines (2013)
A rough opening is 60 by 48 inches and the perimeter joint is 3/8 inch on each side. What is the frame size?
- a.60-3/4 by 48-3/4 inches
- b.59-1/4 by 47-1/4 inches✓
- c.60 by 48 inches
- d.59-5/8 by 47-5/8 inches
Two joints reduce each dimension by 3/4 inch, giving 59-1/4 by 47-1/4. Subtracting one joint gives 59-5/8 by 47-5/8, a frame equal to the opening leaves no joint, and adding the joints makes a frame too big.CSLB C-17 study guide 13E-17 (measurements and calculations)
A frame is to fit a 120-by-96-inch rough opening with a 1/4-inch joint all around. What size is the frame?
- a.120-1/2 by 96-1/2 inches
- b.119-1/2 by 95-1/2 inches✓
- c.119-3/4 by 95-3/4 inches
- d.120 by 96 inches
Two 1/4-inch joints reduce each dimension by 1/2 inch. Subtracting one joint gives 119-3/4, a frame equal to the opening leaves no joint, and adding joints makes the frame too big.CSLB C-17 study guide 13E-17 (measurements and calculations)
A 16-foot run has two jambs and two intermediate mullions, each face 2-1/2 inches, with three equal lites. What is each daylight opening width?
- a.About 60.7 inches✓
- b.About 64 inches
- c.About 67 inches
- d.About 62.5 inches
The run is 192 inches, four faces take 10 inches, and 182 ÷ 3 = 60.7 inches. Dividing 192 by three ignores the faces, 67 adds the faces, and 62 deducts too little.CSLB C-17 study guide 13E-17 (measurements and calculations)
A 20-foot run has two jambs and three intermediate mullions, each face 2 inches, with four equal lites. What is each daylight opening width?
- a.62.5 inches
- b.57.5 inches✓
- c.60 inches
- d.59.5 inches
The run is 240 inches, five faces take 10 inches, and 230 ÷ 4 = 57.5 inches. Dividing 240 by four ignores the faces, 62.5 adds the faces, and 59.5 deducts only one face.CSLB C-17 study guide 13E-17 (measurements and calculations)
Each daylight opening is 57-1/2 inches wide and the bite is 3/8 inch on each side. What is the glass width?
- a.57-7/8 inches
- b.57-1/2 inches
- c.59 inches
- d.58-1/4 inches✓
Two bites add 3/4 inch, giving 58-1/4 inches. The daylight opening alone ignores the bite, 57-7/8 adds one bite, and 59 adds 1-1/2 inches.CSLB C-17 study guide 13E-17 (measurements and calculations)
A skylight lite of 1/2-inch glass is sloped 25 degrees from horizontal. What dead load does the code formula give?
- a.3.25 pounds per square foot
- b.5.9 pounds per square foot
- c.6.5 pounds per square foot✓
- d.4.9 pounds per square foot
At 30 degrees or less from horizontal D = 13 × 0.5 = 6.5 with no cosine. Applying the cosine gives 5.9, 3.25 halves it, and 4.9 uses a 3/8-inch lite.2025 CBC §2404.2
A skylight lite of 1/4-inch glass is sloped 40 degrees from horizontal. What dead load does the code formula give?
- a.About 3.25 pounds per square foot
- b.About 2.1 pounds per square foot
- c.About 2.5 pounds per square foot✓
- d.About 1.6 pounds per square foot
Steeper than 30 degrees, D = 13 × 0.25 × cos 40° = 3.25 × 0.766 = 2.5. Omitting the cosine gives 3.25, using cos 50° gives 2.1, and 1.6 has no basis.2025 CBC §2404.2
Which lite is sloped glazing under the Building Code?
- a.A lite exactly 15 degrees from vertical
- b.A lite 10 degrees from vertical
- c.A vertical lite
- d.A lite 20 degrees from vertical✓
Sloped glazing is glass sloped more than 15 degrees from vertical, so 20 qualifies. Ten degrees, exactly 15 degrees and a vertical lite do not exceed 15.2025 CBC §2404.2, §2405.1
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A glass edge is 10 feet long. What is the code's limit on framing deflection perpendicular to the glass at that edge?
- a.About 0.50 inch
- b.About 0.75 inch
- c.About 1.2 inches
- d.About 0.69 inch✓
For edges up to 13 feet 6 inches the limit is 1/175 of the edge length, 120 ÷ 175 = 0.69 inch. The 3/4 inch is a manufacturer cap, 0.50 is a different fraction, and 1.2 inches is L/100.2025 CBC §2403.3
A glass edge is 16 feet long. What is the code's limit on framing deflection at that edge?
- a.About 1.05 inches✓
- b.About 0.75 inch
- c.About 1.10 inches
- d.About 0.80 inch
Over 13 feet 6 inches the limit is 1/240 of the edge length plus 1/4 inch, 192 ÷ 240 + 0.25 = 1.05 inches. The 1.10 is L/175, 0.80 omits the quarter inch, and 0.75 is the manufacturer cap.2025 CBC §2403.3
Framing bow measured over a 4-foot length is 3/32 inch. The guideline allows 1/16 inch in any four-foot length. What is the result?
- a.It is irrelevant to glazing
- b.It exceeds the limit✓
- c.It meets the limit if shimmed
- d.It meets the limit
3/32 inch is more than 1/16 inch, so the bow is out of tolerance. Shimming does not remove bow in the member, and bow is a framing tolerance that matters to glass support.Viracon Glazing Guidelines - Standard
The guideline limits twist of a horizontal sill under glass weight to what?
- a.No limit applies to sills under glass weight
- b.Less than 1 degree between ends and center✓
- c.Up to 1/2 inch between ends and center
- d.Up to 5 degrees of twist between ends and center
Sill twist is limited to less than 1 degree to avoid mechanical bending stress at the glass edge. Five degrees and 1/2 inch are far looser, and a limit does apply.Pilkington ATS-192 General glazing guidelines (2013)
Which condition can cause thermal stress breakage of annealed glass?
- a.A large sign fastened to one part of the lite✓
- b.Setting blocks at the quarter points of the sill
- c.Even sun falling across the whole lite all day
- d.A clean glazing pocket with open weeps
Signs fastened to the glass interfere with uniform solar heating, a named cause of thermal stress. Uniform sun, a clean pocket and correct blocks are not causes.Pilkington ATS-192 General glazing guidelines (2013)
How far from full closure do lock stops hold louver blinds near insulating glass to limit thermal stress?
- a.About 5 degrees
- b.Fully closed
- c.About 60 degrees
- d.About 30 degrees✓
Lock stops keeping blades about 30 degrees off full closure are described as effective. Five degrees is almost closed, 60 degrees is not the described setting, and fully closed traps heat.Pilkington ATS-192 General glazing guidelines (2013)
What is a mullion?
- a.A frame member that joins two windows into one unit✓
- b.The frame member that runs across the top of an opening
- c.The strip that holds the glass in its glazing pocket
- d.A sloped sill member that is shaped to drain water
A mullion is a frame member used to join two windows into one fenestration unit. The member across the top is a head, a sloped drainage member is a sill flashing or sill pan, and the strip that holds glass is a stop or bead.2025 Energy Code residential compliance manual, Ch. 3
A daylight opening is 80 inches wide and the system says weeps are at the quarter points of the daylight opening. Where are the two weeps measured from one end?
- a.At 40 inches
- b.At 27 inches and 53 inches
- c.At 10 inches and 70 inches
- d.At 20 inches and 60 inches✓
Quarter points of 80 inches are at 20 and 60 inches. A single weep at 40 is the center, 10 and 70 are an eighth from each end, and 27 and 53 are thirds.YKK AP storefront weathering/sealant checklist 02-4100-05
What diameter are the sill flashing weep holes in one storefront manufacturer's checklist?
- a.1 inch
- b.3/4 inch
- c.1/8 inch
- d.5/16 inch✓
The checklist calls for 5/16-inch holes at the quarter points of the daylight opening. One-eighth inch clogs, and 3/4 and 1 inch are far too large.YKK AP storefront weathering/sealant checklist 02-4100-05
Why must setting blocks be set clear of weep holes?
- a.Blocked weeps trap water and cause seal failure✓
- b.Blocks swell and bind when they touch water
- c.Weeps are sized only for air movement in the pocket
- d.Blocks must stay dry for the sealant to bond
Water trapped in the pocket leads to ponding, a primary cause of seal failure in insulating glass units. The guideline does not say blocks swell in water, dryness of the block is not the reason for keeping weeps clear, and weeps are sized to drain water, not just to move air.Pilkington ATS-192 General glazing guidelines (2013)
When is the joinery of a storefront frame sealed?
- a.Before the frame members are assembled✓
- b.Not at all, if the joints are tight
- c.After the glass has been set and stopped
- d.After the frame is set in the opening
Sealant goes on member ends before assembly so the inside of the joint is sealed. Sealing after the frame is set or after glazing reaches only the outside of the joint, and tight-fitting joints still leak without sealant.YKK AP storefront weathering/sealant checklist 02-4100-05
Just before the frame is set on the sill flashing, what does the checklist place along the back leg of the flashing?
- a.A bead of sealant✓
- b.A strip of paper
- c.A foam spacer
- d.A row of shims
A bead of sealant along the top of the flashing's back leg goes down just before the frame is set. Paper, shims and foam do not seal the joint.YKK AP storefront weathering/sealant checklist 02-4100-05
What gap does the checklist allow at a sill flashing splice?
- a.1/32 inch between the members
- b.1/8 inch between members
- c.2 inches between the members
- d.3/8 inch between members✓
The checklist allows a 3/8-inch splice joint between flashing members, sealed with a splice sleeve. An eighth of an inch and 1/32 inch leave too little room for movement, and 2 inches is far too wide.YKK AP storefront weathering/sealant checklist 02-4100-05
What are water deflectors installed on, according to the checklist?
- a.The face of the glass in the lite
- b.The top of the head member only
- c.The heads of the anchors
- d.The end of each horizontal member✓
The checklist directs water deflectors on the end of each horizontal member, sealed along three edges. They are not placed on the head only, the glass face or the anchors.YKK AP storefront weathering/sealant checklist 02-4100-05
How are vertical and horizontal glazing gaskets arranged at a corner in the checklist?
- a.Gaskets stop short of the corner to allow movement
- b.Horizontals run through and the verticals butt to them
- c.Verticals run through; horizontals butt and are sealed✓
- d.Gaskets are mitered at the corner and left unsealed
Vertical gaskets run through and the ends of horizontal gaskets are sealed to them. Running the horizontals through reverses the checklist, mitering without sealant leaves a leak path at the joint, and stopping short of the corner leaves an open gap.YKK AP storefront weathering/sealant checklist 02-4100-05
What is structural sealant glazing?
- a.Glass held in place by screws through the lite
- b.Glass held in the frame by compression gaskets alone
- c.Glass bedded and face-puttied in a steel sash frame
- d.Glass bonded by silicone that carries the loads✓
Structural sealant glazing uses silicone on one or more sides of the unit for the structural transfer of loads from glass to its support. Gasket-only, putty and through-glass screws are other methods.Viracon Glazing Guidelines - Standard
For school and hospital work, what design stress cap and minimum factor of safety does the code set for structural sealant glazing?
- a.20 psi and a factor of safety of 5✓
- b.100 psi and a factor of safety of 1
- c.5 psi and a factor of safety of 20
- d.200 psi and a factor of safety of 2
The code's provisions for those jurisdictions cap allowable stress at 20 psi and require a factor of safety of at least 5. The other pairs are not the code values.2025 CBC §2410.1.1
Holes for door patch fittings in tempered glass must be located and confirmed when?
- a.After glazing, by core drilling the lite on site
- b.Before the glass is ordered and fabricated✓
- c.After the glass arrives, by drilling on site
- d.At glazing, by templating from the frame
All drilling and notching happens before heat treatment, so locations are fixed at order. Site drilling and core drilling break tempered glass, and templating at glazing comes after the lite has already been made.GANA FB45-14 Recommended Applications for Heat-Treated Glass (2019)
A lite of insulating glass is slightly too large in the shop. What is correct?
- a.Order a new unit made to the right size✓
- b.Grind the edge in the shop until it fits
- c.Trim the spacer with snips to gain the room
- d.Nip the corner to relieve the tight fit
Finished insulating units should not be modified by cutting, seaming or grinding, so the remedy is a correctly sized unit. Grinding the edge alters a finished edge, trimming the spacer with snips damages the sealed airspace, and nipping the corner takes glass from a unit that cannot be reworked.Pilkington ATS-192 General glazing guidelines (2013)
Which glass edges are ground smooth in the shop?
- a.Edges that will be hidden inside the pocket
- b.No edges are ground, since factory edges are final
- c.Edges that will be exposed in finish work✓
- d.Only the edges of mirrors and similar lites
The guide specification calls for grinding smooth, in the shop, glass edges that will be exposed. Hidden edges and a mirrors-only rule are not stated.UFGS 08 81 00
Why do metal frames have thermal breaks?
- a.To carry the weight of the glass in the pocket
- b.To reduce heat loss through the frame✓
- c.To add weight so the frame resists wind
- d.To let water in the pocket drain to the outside
A thermal break separates the inside and outside metal with a lower-conductivity material to cut frame heat loss. It does not add weight, carry glass load or drain water.2025 Energy Code residential compliance manual, Ch. 3
Why are frame members dry-fitted before sealant is applied?
- a.To reduce the time that is spent cleaning the shop
- b.To confirm joints close and diagonals match✓
- c.To give the sealant time to cure before assembly
- d.To avoid cutting the members to length
A dry fit shows whether joints close and the frame is square before the sealant makes correction hard. It does not cure sealant, avoid cutting or save cleaning.CSLB C-17 study guide 13E-17 (fabrication of framing systems)
A storefront frame has a head and sill of 10 feet each and three verticals of 7 feet each. How many lineal feet of framing is that?
- a.41 feet✓
- b.37 feet
- c.50 feet
- d.34 feet
Horizontals are 2 × 10 = 20 feet and verticals 3 × 7 = 21 feet, so 41 feet. The 34 counts only two verticals, 50 uses 10 feet for each vertical, and 37 is a guess.CSLB C-17 study guide 13E-17 (job-related calculations)
Why does the storefront specification require field verification of dimensions before fabricating components?
- a.Openings and adjoining work differ from the drawings✓
- b.The building department requires it for the permit
- c.The frame is cut on site from the field sizes
- d.The supplier needs it to quote the unit price
Real openings and adjacent construction vary from the drawn dimensions, so components that depend on them are fabricated from verified sizes. A permit requirement is not the reason given, pricing does not depend on field verification, and the specification calls for shop fabrication, not cutting the frame on site.UFGS 08 41 13
What is the correct order of work when setting a storefront frame?
- a.Verify the opening, set and shim, then anchor✓
- b.Seal the perimeter joint first, then set the frame into the sealant
- c.Glaze the frame first, then brace it in place
- d.Anchor the frame first, then shim it to alignment
The specification sequence is to verify the opening, set the frame, then shim and brace before anchoring. Anchoring first locks in any error, sealing the perimeter joint first leaves no room to adjust the frame, and glazing before bracing loads an unstable frame.UFGS 08 41 13
Where does a storefront manufacturer's checklist call for shims?
- a.Nowhere, since the anchors align the frame
- b.Only under the glass, at the sill
- c.Only at the head and sill
- d.At the head, sill and jambs✓
Shims are used at the head, sill and jambs to set the frame plumb, level and square and to leave room for the backer and sealant. Head-and-sill shims leave the jambs unaligned, shimming under the glass is a different task, and anchors alone do not set the frame plumb and square.YKK AP storefront weathering/sealant checklist 02-4100-05
What is the maximum shim stack in the product-approval detail?
- a.2 inches
- b.1/4 inch
- c.1/2 inch✓
- d.1 inch
The detail limits shim stacks to 1/2 inch. Two inches and 1 inch exceed it, and 1/4 inch is stricter than the detail.Arcadia IPTC-470 installation details, Florida approval FL40951
At what gap size does the detail call for a shim?
- a.Wherever the space is 1/16 inch or more✓
- b.Only where the space exceeds 1 inch in width
- c.Only at the corners of the opening and sill
- d.Wherever the space is 1/2 inch or more
The detail calls for a shim wherever the space is 1/16 inch or greater. A 1-inch or 1/2-inch trigger leaves smaller gaps unsupported, and a corner-only rule leaves the rest of the perimeter open.Arcadia IPTC-470 installation details, Florida approval FL40951
What separates aluminum framing from a masonry sill?
- a.A nylon pad or a bituminous coating✓
- b.A bed of mortar under the aluminum sill
- c.Bare contact with the masonry surface
- d.A coat of lacquer on the masonry surface
The guide specification protects aluminum in contact with masonry, steel or concrete with nylon pads or a bituminous coating. Mortar attacks aluminum, bare contact corrodes, and lacquer is not the specified protection.UFGS 08 41 13
Aluminum is fastened to a dissimilar metal other than stainless steel or zinc. What is required?
- a.Protect the aluminum from the dissimilar material✓
- b.Paint over both metals after the sealant is applied
- c.Add a second fastener at each connection point
- d.Nothing, since all of these metals are compatible
The specification requires protecting aluminum surfaces from dissimilar materials. Metals are not all compatible, painting over sealant surfaces prevents adhesion, and a second fastener adds more metal contact without isolating anything.UFGS 08 51 13
Aluminum must be protected from which contaminants?
- a.Clean water used to rinse the finish
- b.Lime, mortar, cement and harsh acids✓
- c.Normal daylight on the exposed surface
- d.Neoprene gaskets in the glazing pocket
The specification protects aluminum from lime, mortar, cement, acids and other harmful contaminants. Clean water, daylight and neoprene gaskets are not named.UFGS 08 41 13
Why should coatings and lacquers not be applied to surfaces where caulking must adhere?
- a.They cause the weep holes to fill and close up
- b.They can keep the sealant from adhering✓
- c.They make the metal brittle at the joint
- d.They change the apparent color of the glass
The specification forbids coating surfaces to which caulking and glazing components must adhere because the coating becomes the bond line. A coating does not make metal brittle, it does not change the color of the glass, and it is not what closes weep holes.UFGS 08 51 13
At what locations does the checklist call for backer rods and perimeter sealant?
- a.Head, sill and jambs, at both faces✓
- b.The glass edge and nowhere else
- c.The exterior sill and nowhere else
- d.The interior head and nowhere else
The checklist calls for backer rods and perimeter seal at head, sill and jambs on both faces. A single location leaves the other joints open.YKK AP storefront weathering/sealant checklist 02-4100-05
When are perimeter anchor fastener heads sealed?
- a.Only after the building is occupied
- b.Before the anchors are installed
- c.Only at the corners of the frame
- d.After the frame is anchored in place✓
The checklist seals all perimeter anchor fastener heads after anchoring. Sealing before installation covers nothing, sealing only the corners leaves the other heads open, and waiting until occupancy leaves leak paths in the meantime.YKK AP storefront weathering/sealant checklist 02-4100-05
How does the aluminum window specification say windows are placed in their openings?
- a.Attached before the opening has been measured
- b.Plumb, square and level, braced against distortion✓
- c.Forced into the opening with a hammer if needed
- d.Left loose in the opening until after the glass is set
Windows are set plumb, square, level and in alignment and braced to prevent distortion, without forcing. Forcing, leaving them loose and installing before measuring all risk distortion.UFGS 08 51 13
What does the aluminum window specification say to do with screws and bolts in sill members?
- a.Coat them with paint to protect the thread surfaces
- b.Cover them with foam before the frame is set
- c.Leave them bare so that any water can drain past them
- d.Bed them in the manufacturer's mastic sealant✓
Screws and bolts in sill members, joints at mullions and contacts with sills are bedded in the manufacturer's recommended mastic sealant. Bare fasteners leave a path for water, paint does not seal a threaded penetration, and foam is not a sealant and does not stay in place.UFGS 08 51 13
How deep must window head and jamb members recess into masonry in the guide specification?
- a.Not less than 7/16 inch✓
- b.No recess is required
- c.Not less than 3 inches
- d.Exactly 1/16 inch
The recess is not less than 7/16 inch. A recess is required, 3 inches is not stated, and 1/16 inch is too little.UFGS 08 51 13
How are entrance thresholds installed in the guide specification?
- a.Set in mortar with no mastic bedding at all
- b.Set on foam with no mechanical fasteners
- c.Set in a bed of mastic, then secured✓
- d.Set dry on the slab and held by the door
Thresholds are set in a bed of mastic and secured. Dry setting leaks, and mortar and foam are not the specified bedding.UFGS 08 41 13
A completed storefront is 10 feet by 14 feet. The specification limit is 0.06 cfm per square foot. What is the maximum allowable infiltration?
- a.140 cfm
- b.24 cfm
- c.8.4 cfm✓
- d.0.84 cfm
The area is 140 square feet and 140 × 0.06 = 8.4 cfm. The 0.84 shifts the decimal, 140 is the area, and 24 is half the perimeter in feet.UFGS 08 41 13
A pair of entrance doors and its frame fill an opening 7 feet wide by 8 feet high, with a limit of 1.2 cfm per square foot. What is the maximum infiltration?
- a.30 cfm
- b.67.2 cfm✓
- c.56 cfm
- d.6.72 cfm
The pair covers 56 square feet and 56 × 1.2 = 67.2 cfm. The 56 is the area, 6.72 shifts the decimal, and 30 is the perimeter in feet.UFGS 08 41 13