CSLB C-39 Roofing (Trade Exam) — All Questions
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42 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
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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
Under the CBC, where is flashing required?
- a.At penetrations that are over 12 inches wide
- b.Along the outside roof edges and the eaves
- c.At walls, gutters, slope changes and roof openings✓
- d.On the windward side of the roof in high wind
CBC 1503.2.1 calls for flashing at wall and roof intersections, at gutters, wherever the slope or direction changes, and around roof openings. Limiting it to edges, large penetrations or the windward side leaves leak paths open.2025 CBC 1503.2.1
What must the top surface of a parapet wall provide under the CBC?
- a.A level seat for coping stones
- b.A sealant joint along its length
- c.Positive drainage✓
- d.A raised crown at the center
The top of a parapet wall must provide positive drainage so water does not pond or enter the wall. A level seat would hold water, a crown is not required, and a sealant joint alone does not drain the surface.2025 CBC 1503.3
The CBC says intake and exhaust vents for attics are provided according to Section 1202.2 and which other source?
- a.The vent product manufacturer's instructions✓
- b.The roof covering warranty terms
- c.The owner's utility bill history
- d.The flashing manufacturer's color chart
Vents must follow Section 1202.2 and the vent product manufacturer's installation instructions. A covering warranty, a color chart or utility history is not an installation requirement for vents.2025 CBC 1503.4
Gutters that secure the perimeter edge of a low-slope membrane must be tested to which methods?
- a.RE-1, RE-2 and RE-3 of ES-1
- b.ASTM E108 and UL 790
- c.G-1 and G-2 of SPRI GT-1✓
- d.ASTM D3746 and D4272
Gutters used to secure the membrane perimeter are tested under methods G-1 and G-2 of SPRI GT-1. RE-1 through RE-3 of ES-1 are for other metal edge systems, E108 and UL 790 are fire tests, and D3746 and D4272 are impact tests.2025 CBC 1504.6.1
The CBC says flashing must stop water from entering the wall and roof through which of these?
- a.Gaps beside nailed ridge caps and along the hips
- b.Holes drilled for tie-downs and fasteners
- c.Joints in copings and moisture-permeable materials✓
- d.Seams between insulation boards in the assembly
Flashing is to prevent water entry through joints in copings, through moisture-permeable materials and at intersections with parapet walls and other penetrations. Ridge caps, tie-down holes and insulation seams are not the situations that section names.2025 CBC 1503.2
Which type of low-slope roof must have parapets complying with CBC Table 1504.8?
- a.Roofs with a white membrane
- b.Aggregate-surfaced roofs✓
- c.Roofs with standing seams
- d.Roofs with a vegetated cover
Parapets are required for aggregate-surfaced roofs so loose stone does not wash or blow off the edge. Membrane color, standing seams and vegetation are not the trigger in that section.2025 CBC 1504.8
Ballasted low-slope single-ply roofs must be designed in accordance with which standard?
- a.ANSI/SPRI RP-4✓
- b.FM 4474
- c.SPRI GT-1
- d.ANSI/SPRI ES-1
Ballasted single-ply systems follow ANSI/SPRI RP-4. ES-1 covers metal edge systems, GT-1 covers gutters, and FM 4474 is a wind-uplift test for membrane coverings.2025 CBC 1504.5
Above-deck thermal insulation under a roof covering must comply with which pair of standards?
- a.ASTM C1289 or ASTM C728
- b.NFPA 276 or UL 1256✓
- c.FM 4474 or UL 580
- d.ASTM E108 or UL 790
Above-deck insulation must be covered with a roof covering and comply with NFPA 276 or UL 1256 as an assembly. C1289 and C728 are insulation material standards, E108 and UL 790 are roof fire classification tests, and FM 4474 and UL 580 are uplift tests.2025 CRC R906.1
Gutters and leaders on the outside of a Type I commercial building must be made of what, under the CBC?
- a.Aluminum or copper sheet metal in standard gauges
- b.Galvanized steel sheet metal in standard gauges
- c.Noncombustible, or at least Schedule 40 plastic pipe✓
- d.Sheet material of the owner's choice
Outside gutters and leaders must be noncombustible or not less than Schedule 40 plastic pipe, except for Group R-3, private garages and Type V buildings. Material is not limited to one metal or left to any sheet product.2025 CBC 1502.3
TPO single-ply membrane falls under which ASTM standard in the CBC table?
- a.ASTM D4637
- b.ASTM D6878✓
- c.ASTM D4434
- d.ASTM D6162
TPO membrane is listed under ASTM D6878. D4637 is EPDM, D4434 is PVC, and D6162 is a modified bitumen sheet standard.2025 CBC Table 1507.12.2
Which ASTM standard does the CBC table list for aggregate surfacing on a built-up roof?
- a.ASTM D2178
- b.ASTM D448
- c.ASTM D4601
- d.ASTM D1863✓
Aggregate surfacing for built-up roofs is listed under ASTM D1863. D448 covers ballast stone for single-ply roofs, D2178 is glass felt, and D4601 is the glass fiber base sheet.2025 CBC Table 1507.10.2
Besides the base sheets in Section 1507.11.2, which standards may a base sheet meet when used with a modified bitumen cap sheet?
- a.ASTM D1970 or D4601✓
- b.ASTM D448 or D7655
- c.ASTM D3909 or D6083
- d.ASTM D226 or D1863
The CBC permits a base sheet complying with ASTM D1970 or D4601 under a modified bitumen cap sheet. D3909 is a mineral-surfaced cap sheet and D6083 an acrylic coating, D226 is organic felt and D1863 aggregate, and D448 and D7655 are ballast stone.2025 CBC 1507.11.2.1
Asphalt glass felt for a built-up roof is assigned to which standard in the CBC table?
- a.ASTM D2178✓
- b.ASTM D4601
- c.ASTM D226
- d.ASTM D1863
Asphalt glass felt is listed under ASTM D2178. D226 is asphalt-saturated organic felt, D4601 is the asphalt-coated glass fiber base sheet, and D1863 is aggregate surfacing.2025 CBC Table 1507.10.2
Why does a spray polyurethane foam roof rely on a protective coating, according to the DOE?
- a.Foam is susceptible to mechanical, moisture and UV damage✓
- b.The foam cannot be made watertight without a top layer
- c.The foam shrinks and loses thickness if left uncoated in sun
- d.The foam becomes fire rated when it is coated
The DOE explains that foams are highly susceptible to mechanical, moisture and UV damage, so they depend on a protective coating. The other reasons are not what the DOE gives.DOE Guidelines for Selecting Cool Roofs
What does the DOE call a built-up roof that is surfaced with a modified bitumen sheet?
- a.A ballasted roof
- b.A hybrid roof✓
- c.A flood-coat roof
- d.A protected membrane roof
The DOE says a modified bitumen sheet can be used to surface a built-up roof and calls the result a hybrid roof. A ballasted roof is held down with stone, a flood-coat roof is surfaced with embedded gravel, and a protected membrane roof places insulation above the membrane.DOE Guidelines for Selecting Cool Roofs
The DOE lists three ways a single-ply sheet may be secured to a roof. Which set is correct?
- a.Mechanical fasteners, adhesives, or ballast✓
- b.Torch welding, hot mopping, or nailing on a deck
- c.Solvent welding, bead sealant, or sand fill
- d.Battens, hold-down clips, or standing seams
Single-ply sheets are rolled out and attached with mechanical fasteners, adhered with chemical adhesives, or held down with ballast. Torching and hot mopping belong to bituminous systems, and battens, clips and seams belong to metal panels.DOE Guidelines for Selecting Cool Roofs
A roof coating is to be installed. In addition to the CRC coating section, how must it be installed?
- a.Per the roofer's usual practice on similar jobs
- b.Per the owner's preferred coating thickness
- c.Per the manufacturer's installation instructions✓
- d.Per the method used on the neighboring roof
The CRC says roof coatings shall be installed in accordance with the manufacturer's installation instructions. Usual practice, a neighbor's method or an owner preference does not replace them.2025 CRC R909.1
An applied roof coating must still comply with which other CRC sections?
- a.R902 for fire and R904 for materials✓
- b.R1001 for chimneys and R1003 for hearths
- c.R703 for walls and R806 for venting
- d.R301 for loads and R302 for fire separation
The CRC says roof coating installation shall comply with Section R902, Section R904 and the coating section itself. The other pairs deal with loads, walls, venting or chimneys, not roof classification or materials.2025 CRC R909.1
Which ASTM standard does the CRC list for silicone roof coatings?
- a.ASTM D6083
- b.ASTM D3468
- c.ASTM D6947
- d.ASTM D6694✓
Silicone coating is listed under ASTM D6694. D6083 covers acrylic coatings, D6947 covers moisture-cured polyurethane, and D3468 covers liquid-applied roofing.2025 CRC R909.2
A homeowner wants to brush leftover house paint over a worn membrane. What does the DOE say?
- a.Ordinary paints are not designed to last on roofs✓
- b.Paint is acceptable if it is a white acrylic
- c.Paint is acceptable over a single-ply membrane
- d.Paint is acceptable in a dry, mild climate zone
The DOE says roof coatings are not the same as exterior paints, because ordinary paints are not designed to last on roofs or to protect them. Color, substrate and climate do not change that.DOE Guidelines for Selecting Cool Roofs
The DOE describes one coating type as water based and easy to handle. Which type is it?
- a.Acrylic✓
- b.Silicone
- c.Coal-tar pitch
- d.Aluminized asphaltic emulsion
The DOE lists acrylic coatings as water based and easy to handle with good adhesion. Silicone is described as solvent based and typically used on spray foam, and the emulsion and pitch are different materials.DOE Guidelines for Selecting Cool Roofs
Which product gives a glossy finish on some roofs but falls short of cool-roof standards on low slopes, per the DOE?
- a.Solvent-based silicone coating
- b.A white reflective TPO membrane
- c.Water-based acrylic coating
- d.Aluminized asphaltic emulsion✓
The DOE says aluminized asphaltic emulsions give a glossy finish but fall short of cool roof standards on low-sloped roofs. Acrylic, white TPO and silicone are products it treats as able to be reflective.DOE Guidelines for Selecting Cool Roofs
A membrane is to be adhered with chemical adhesive in cool weather. What does the DOE say about the membrane?
- a.It bonds best when it is cooled below ambient air
- b.It must reach and hold a minimum temperature✓
- c.It needs a primer coating before it is adhered
- d.It needs ballast stone over the wet adhesive
Membranes attached with chemical adhesives must reach and maintain a minimum temperature to bond properly. Chilling it, adding ballast or pre-coating does not address that.DOE Guidelines for Selecting Cool Roofs
How do the DOE guidelines say SPF roofs are kept up over time?
- a.Periodic re-coating with a reflective coating✓
- b.Painting them with ordinary exterior house paint
- c.Stripping off the coating completely each season
- d.Replacing the foam layer every year
SPF roofs are typically coated and periodically re-coated with reflective coatings to protect the foam from UV and water damage. Yearly foam replacement, seasonal stripping and house paint are not described.DOE Guidelines for Selecting Cool Roofs
A commercial low-slope roof with positive drainage is being recovered, and its actual slope is under 1/4:12. Must the slope be raised?
- a.Yes; unless the new roof coating is reflective white
- b.No; slope rules do not apply to existing roofs
- c.Yes; 1/4:12 is mandatory for a reroof
- d.No; this exception covers roofs that already shed water✓
Roof replacement or recover of low-slope coverings need not meet the 1/4:12 minimum where the roof has positive drainage. The minimum is not mandatory for every reroof, coating color is irrelevant, and the rule is an exception rather than a blanket exemption.2025 CBC 1512.1