CSLB C-39 Roofing (Trade Exam) — All Questions

What minimum design slope does the CRC require for a modified bitumen roof, for drainage?

• a.1/8 inch per foot
• b.1/4 inch per foot✓
• c.1 inch per foot
• d.1/2 inch per foot

Modified bitumen roofing needs a design slope of at least one-fourth unit vertical in 12 horizontal (2 percent) for drainage. One-eighth is allowed only for coal-tar built-up roofs.2025 CRC R905.11.1

Which standards may spray-applied polyurethane foam roofing insulation meet under the CRC?

• a.ASTM C1029 or D7425✓
• b.ASTM D3462 or D7158
• c.ASTM D226 or D4869
• d.ASTM C1167 or C1492

SPF roofing foam must comply with ASTM C1029 Type III or IV or ASTM D7425. D226 is felt underlayment, D3462 asphalt shingles and C1167 clay tile.2025 CRC R905.13.2

A foam crew finishes spraying at 9:00 a.m. What is the EARLIEST the protective coating may be applied?

• a.11:00 a.m.✓
• b.The next morning
• c.After 72 hours
• d.9:30 a.m.

The coating must be applied not less than 2 hours nor more than 72 hours after the foam. Two hours after 9:00 a.m. is 11:00 a.m.; 72 hours is the latest limit, not the earliest.2025 CRC R905.13.3

Which set of standards does the CBC list for liquid-applied roofing?

• a.ASTM C836, C957 or D3468✓
• b.ASTM C406, C1167 or C1492
• c.ASTM D4637, D6878 or D4434
• d.ASTM D226, D4869 or D1970

Liquid-applied roofing must comply with ASTM C836, ASTM C957 or ASTM D3468. D4637 and D6878 are single-ply standards; D226 and D4869 are felts.2025 CBC 1507.14.2

Which ASTM standard does the CBC list for EPDM single-ply membrane?

• a.ASTM D4434
• b.ASTM D5019
• c.ASTM D6878
• d.ASTM D4637✓

The single-ply table lists EPDM under ASTM D4637, PVC under D4434, TPO under D6878, and CSPE or PIB under D5019.2025 CBC Table 1507.12.2

Which ASTM standard does the CBC list for PVC single-ply membrane?

• a.ASTM D4434✓
• b.ASTM D4637
• c.ASTM D6878
• d.ASTM D6754

PVC or PVC/KEE membranes are listed under ASTM D4434. D4637 is EPDM, D6878 TPO and D6754 KEE.2025 CBC Table 1507.12.2

Which standard covers the mineral-surfaced inorganic cap sheet used on built-up roofs?

• a.ASTM D41
• b.ASTM D3909✓
• c.ASTM D1863
• d.ASTM D312

The built-up roofing table lists mineral-surfaced inorganic cap sheet under ASTM D3909. D1863 is aggregate, D41 asphalt primer and D312 roofing asphalt.2025 CBC Table 1507.10.2

Which standard covers the asphalt itself used in built-up roofing?

• a.ASTM D450
• b.ASTM D312✓
• c.ASTM D2178
• d.ASTM D4601

Asphalt used in roofing is listed under ASTM D312. D450 is coal-tar pitch, D2178 asphalt glass felt and D4601 glass fiber base sheet.2025 CRC Table R905.9.2

Which coating is NOT among the protective coatings the CBC lists for spray polyurethane foam roofs?

• a.Aluminum-pigmented asphalt coating✓
• b.Acrylic coating
• c.Moisture-cured polyurethane coating
• d.Silicone coating

The SPF protective coating table lists acrylic (D6083), silicone (D6694) and moisture-cured polyurethane (D6947). Aluminum-pigmented asphalt coating appears in the general roof coating table, not the SPF table.2025 CBC Table 1507.13.3

Which metal component on a low-slope single-ply roof is excluded from the ANSI/SPRI ES-1 edge-system testing rule?

• a.Gravel stop edge metal
• b.Metal fascia edge
• c.Metal coping on the roof edge
• d.Counterflashing✓

The CBC applies ES-1 testing to metal edge systems on built-up, modified bitumen and single-ply roofs, except gutters and counterflashing.2025 CBC 1504.6

A 36-inch-wide skylight curb (not a listed unit skylight flashed per its instructions) sits on a low-slope roof. What is required on its upslope side?

• a.A walkway pad
• b.Nothing if the membrane is fully adhered
• c.A pitch pan
• d.A cricket✓

A cricket or saddle is required on the ridge side of any chimney or penetration greater than 30 inches wide measured perpendicular to the slope. Listed unit skylights flashed per the manufacturer are excepted.2025 CBC 1503.5

How wide must a parapet coping be?

• a.Half the wall thickness
• b.Any width, if sealed
• c.Wall thickness or wider✓
• d.At least 6 inches wider than the wall

Parapet walls must be coped with noncombustible, weatherproof materials of a width not less than the thickness of the parapet wall.2025 CRC R903.3

Which ASTM standard does the CBC list for perlite board roof insulation?

• a.ASTM C1289
• b.ASTM C208
• c.ASTM C578
• d.ASTM C728✓

Perlite board is listed under ASTM C728. C1289 covers polyisocyanurate, C578 polystyrene and C208 wood fiberboard.2025 CBC Table 1508.2

A house's low-slope roof has positive drainage but no overflow scuppers. The owner is replacing the roof covering. Must overflow scuppers be added?

• a.Yes, on every reroof
• b.No; the exception covers it✓
• c.Only if the new roof is single-ply
• d.Yes, if the roof is over 1,000 sq ft

For roofs that provide positive drainage, recovering or replacing an existing roof covering does not require adding secondary (emergency overflow) drains or scuppers.2025 CRC R908.1 exception

Why does unpainted metal fail to qualify as a cool roof on low-slope roofs, according to the DOE?

• a.It cannot be recoated
• b.It is too heavy
• c.Low thermal emittance✓
• d.Its solar reflectance is too low

The DOE notes that unpainted metal roofs tend to have high reflectance but low thermal emittance, which keeps them from being considered cool in low-slope applications.DOE Guidelines for Selecting Cool Roofs

Which standard covers coal-tar pitch used in roofing?

• a.ASTM D312
• b.ASTM D41
• c.ASTM D450✓
• d.ASTM D6083

Coal tar used in roofing is listed under ASTM D450, Type I or II. D312 is roofing asphalt, D41 asphalt primer and D6083 acrylic coating.2025 CRC Table R905.9.2

Which tests does the CRC list for the wind resistance of single-ply roofing?

• a.ASTM E108, E119 or E1592
• b.ASTM D7158, D3161 or D3462
• c.FM 4474, UL 580 or UL 1897✓
• d.UL 2703, UL 7103 or UL 790

Single-ply roofing is tested to FM 4474, UL 580 or UL 1897. D7158 and D3161 are shingle wind tests, and E108 and UL 790 are fire tests.2025 CRC R905.12.4