CSLB C-39 Roofing (Trade Exam) — All Questions
26 questions
What is the minimum number of fasteners for an individual (non-strip) asphalt shingle?
- a.Two✓
- b.Four
- c.One
- d.Six
The CRC requires at least the manufacturer's number of fasteners, but not less than four per strip shingle or two per individual shingle.2025 CRC R905.2.6
What minimum head diameter must an asphalt shingle roofing nail have?
- a.3/8 inch✓
- b.5/16 inch
- c.1/2 inch
- d.1/4 inch
Asphalt shingle nails need a minimum 3/8-inch-diameter head and a 12-gage shank. The 5/16-inch head is the tile nail minimum.2025 CRC R905.2.5
What minimum shank size must an asphalt shingle roofing nail have?
- a.12-gage✓
- b.18-gage
- c.14-gage
- d.16-gage
Asphalt shingle fasteners need at least a 12-gage [0.105 inch] shank. The 11-gage figure is the minimum for tile nails.2025 CRC R905.2.5
To which standard must asphalt shingles comply under the CRC?
- a.ASTM D226
- b.ASTM C406
- c.ASTM D3462✓
- d.ASTM D3909
Asphalt shingles comply with ASTM D3462. D226 is felt underlayment, D3909 mineral-surfaced roll roofing and C406 slate.2025 CRC R905.2.4
Concrete tile is installed at 3:12. What underlayment application is required?
- a.Double underlayment✓
- b.A single layer lapped 2 inches
- c.Self-adhered membrane at the eaves only
- d.No underlayment
For tile slopes from 2-1/2:12 to 4:12, double underlayment application is required. A single layer lapped 2 inches is the method at 4:12 and steeper.2025 CRC R905.3.2
In an area designated for ice barriers, which building does NOT need one?
- a.A two-story house
- b.A house with a 12:12 roof
- c.A detached unheated shed✓
- d.A heated garage attached to a house
The ice barrier requirement has an exception for detached accessory structures not containing conditioned floor area.2025 CRC R905.1.2 exception
Step flashing is installed where shingles meet a wall covered with lap siding. Where does the flashing's vertical leg go?
- a.On top of the siding, sealed
- b.Behind the sheathing
- c.Cut off at the siding's bottom edge
- d.Continuous under the siding✓
Where siding is provided on the vertical sidewall, the vertical leg of the sidewall flashing must be continuous under the siding.2025 CRC R905.2.8.3
What is the minimum thickness of corrosion-resistant metal cap flashing on an asphalt shingle roof?
- a.0.032 inch
- b.0.019 inch✓
- c.0.010 inch
- d.0.0125 inch
Cap flashing must be corrosion-resistant metal of minimum nominal 0.019-inch thickness, the same minimum as metal base flashing.2025 CRC R905.2.8.1
When must valley linings be installed on an asphalt shingle roof?
- a.After the shingles, as a cover
- b.Before the shingles✓
- c.Only on slopes below 4:12
- d.Only when the valley is closed
Valley linings shall be installed in accordance with the manufacturer's instructions before applying shingles.2025 CRC R905.2.8.2
Which copper valley lining meets the CRC table for asphalt shingle open valleys?
- a.Copper-colored paint on steel
- b.Copper foil tape
- c.16 oz cold-rolled copper✓
- d.8 oz copper sheet
The table lists cold-rolled copper of 0.0216 inch nominal, ASTM B370, 16 oz per square foot (and high-yield copper at 12 oz).2025 CRC Table R905.2.8.2
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What minimum height must the splash diverter rib on clay tile valley flashing have?
- a.2 inches
- b.3/4 inch
- c.1/2 inch
- d.1 inch✓
Tile valley flashing extends at least 11 inches each way and has a splash diverter rib at least 1 inch high. The 3/4-inch rib is the metal roof shingle rule.2025 CRC R905.3.9
What minimum head size must a nail for clay or concrete tile have?
- a.5/16 inch✓
- b.3/8 inch
- c.1/4 inch
- d.1/2 inch
Tile nails must be at least 11-gage with a 5/16-inch head. The 3/8-inch head is the asphalt shingle rule.2025 CRC R905.3.7
Concrete tile is installed in an area subject to snow. How many fasteners per tile are required at minimum?
- a.One
- b.One on every other row
- c.None below 5:12
- d.Two✓
In areas subject to snow, not less than two fasteners per tile are required.2025 CRC R905.3.8
Concrete tile is laid on solid sheathing without battens at 3:12 (no snow, no wind design, tile over 9 psf). How are field tiles fastened?
- a.Two fasteners per tile
- b.One fastener per tile✓
- c.No fasteners needed below 5:12
- d.One fastener every other row
On solid sheathing without battens, the table requires one fastener per tile at all slopes. The no-fastener entry below 5:12 applies to spaced sheathing or solid sheathing with battens.2025 CRC Table R905.3.8
Which ASTM standard must roofing slate meet under the CRC?
- a.ASTM C1167
- b.ASTM D3462
- c.ASTM C1492
- d.ASTM C406✓
Slate shingles comply with ASTM C406. C1167 is clay tile, C1492 concrete tile and D3462 asphalt shingles.2025 CRC R905.6.4
What minimum metal does the CRC require for slate valley and flashing metal?
- a.Any painted steel
- b.0.0179-inch G90 steel✓
- c.0.0125-inch G60 steel
- d.0.010-inch aluminum
Slate valley and flashing metal must be a minimum uncoated thickness of 0.0179 inch, zinc-coated G90, and valley flashing at least 15 inches wide.2025 CRC R905.6.7
Slate is installed on a very steep 22:12 mansard. What minimum headlap does the table require?
- a.6 inches
- b.3 inches
- c.2 inches✓
- d.4 inches
At slopes of 20:12 and steeper the minimum slate headlap is 2 inches; 3 inches applies from 8:12 to below 20:12 and 4 inches from 4:12 to below 8:12.2025 CRC Table R905.6.6
Which rule applies to joints in wood shingle courses?
- a.Only the starter course has a joint rule
- b.Joints must line up every other course
- c.No joints aligned in any three adjacent courses✓
- d.Joints may align if they are sealed
Wood shingles are laid with a side lap of at least 1-1/2 inches between joints in courses, and no two joints may be in direct alignment in any three adjacent courses.2025 CRC R905.7.6
Which nail does the table specify for 24-inch wood shingles?
- a.4d box nails✓
- b.3d box nails
- c.8d common nails
- d.6d box nails
The table specifies 3d box nails for 16- and 18-inch shingles and 4d box nails (1-1/2 in x 0.076) for 24-inch shingles.2025 CRC Table R905.7.6(2)
What is the minimum felt used as interlayment strips between courses of wood shakes?
- a.18-inch strips of No. 30 felt✓
- b.12-inch strips of No. 15 felt
- c.Self-adhered membrane strips
- d.36-inch strips of house wrap
Shakes are interlaid with 18-inch-wide strips of not less than No. 30 felt, positioned so the felt is not exposed to the weather.2025 CRC R905.8.8
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What minimum grade must naturally durable wood shakes meet?
- a.No. 3
- b.No. 1✓
- c.No. 2
- d.Any grade if labeled
The shake material table requires No. 1 grade for wood shakes of naturally durable wood under the Cedar Shake and Shingle Bureau rules.2025 CRC Table R905.8.5
What is the minimum slope for a lapped, nonsoldered-seam metal roof installed without lap sealant?
- a.1/2:12
- b.2:12
- c.3:12✓
- d.1/4:12
Lapped, nonsoldered-seam metal roofs without applied lap sealant need a 3:12 slope; with lap sealant, 1/2:12; standing seam, 1/4:12.2025 CRC R905.10.2
What minimum weight does the CRC table set for cold-rolled copper sheet roofing (not high-yield)?
- a.8 oz per sq ft
- b.16 oz per sq ft✓
- c.20 oz per sq ft
- d.12 oz per sq ft
The metal roof covering table sets ASTM B370 copper at a minimum of 16 oz/sq ft, or 12 oz/sq ft for high-yield copper.2025 CRC Table R905.10.3(1)
Where must required attic ventilation openings open?
- a.Into the garage
- b.Directly outdoors✓
- c.Into the living space
- d.Into a wall cavity
Required ventilation openings must open directly to the outside air and be protected against birds, rodents, snakes and similar creatures.2025 CRC R806.1
How does the NPS clay tile brief describe removing a single broken tile?
- a.Break it out with a hammer from above
- b.Pry up the course above with a crowbar
- c.Leave it and seal the crack
- d.Cut its nails with a ripper or hacksaw blade✓
The NPS says a broken tile should be carefully removed with a slate ripper or hacksaw blade inserted under the tile to cut the nails holding it.NPS Preservation Brief 30
Why does the NPS say slate should be laid with copper or stainless steel nails?
- a.Steel nails crack the slate when driven
- b.Stainless nails need no pre-punched holes
- c.Copper nails are cheaper
- d.Steel nails rust out first✓
The NPS explains that plain steel and galvanized nails usually rust out long before the slate begins to deteriorate, which is a common cause of slate loss.NPS Preservation Brief 29