CSLB B-2 Residential Remodeling (Trade Exam) — All Questions

A 3:12 roof will receive asphalt shingles. What does the CRC require?

• a.No underlayment
• b.Metal covering
• c.Double underlayment✓
• d.Single underlayment

Asphalt shingles are permitted from 2:12, and between 2:12 and 4:12 double underlayment is required. Single or no underlayment is not enough, and shingles are allowed at that slope.2025 CRC R905.2.2

What is the minimum 12-gage shingle nail head size, and how far must it penetrate into sheathing?

• a.A 1/8-inch head, penetrating 1/4 inch
• b.A 3/8-inch head, penetrating 3/4 inch✓
• c.A 3/4-inch head, penetrating 2 inches
• d.A 1/2-inch head, penetrating 1/2 inch

Roofing nails have a minimum 3/8-inch head and penetrate at least 3/4 inch into the sheathing, or through sheathing thinner than that. A 1/8-inch head would pull through, a 3/4-inch head with 2-inch penetration is not the stated pair, and 1/2 inch of penetration is too shallow.2025 CRC R905.2.5

A roof tear-off is planned on a house with two layers of shingles. What does R908.3 require?

• a.Removal of all layers down to the roof deck✓
• b.Covering over both layers
• c.Leaving the second layer in place as underlayment
• d.Removal of the top layer

Replacement removes all layers down to the roof deck, with narrow exceptions for sound ice barrier or self-adhered underlayment. Removing only the top layer, covering both layers and leaving a second layer as underlayment are recover practices the replacement rule does not allow.2025 CRC R908.3

Under Cal/OSHA's residential roofing rule, a 9:12 roof has an eave 4 feet above grade. Is fall protection required?

• a.Yes, because the slope is greater than 7:12✓
• b.No, because the eave is under 6 feet
• c.No, because it is a house
• d.Yes, if the roof is wet

On slopes greater than 7:12, protection is required regardless of height. The 6-foot trigger applies only up to 7:12, and houses are what the section covers, so being a house is no exemption. A wet roof is not the trigger either, since slope alone decides.8 CCR 1731(c)(2)

What does the CRC require behind exterior wall finishes?

• a.A vapor retarder, with nothing else behind the siding
• b.Paint applied directly on the sheathing boards
• c.Nothing if siding is vinyl
• d.At least one layer of water-resistive barrier✓

At least one layer of water-resistive barrier covers studs or sheathing on all exterior walls. A vapor retarder alone does not shed water, paint on sheathing is not a barrier, and vinyl siding does not remove the requirement.2025 CRC R703.2

How far above the ground must vinyl siding be kept?

• a.At least 12 inches
• b.At least 1 inch
• c.At least 6 inches✓
• d.At least 2 inches

Vinyl siding keeps at least 6 inches from the ground and 1/2 inch from adjacent surfaces. One and two inches are too close, and 12 inches is more than the minimum.2025 CRC R703.3.1

How many coats of cement plaster are required over metal lath?

• a.One coat of cement plaster
• b.Two coats of cement plaster
• c.At least three✓
• d.Five coats of cement plaster

Over metal or wire lath, plaster is at least three coats. One or two coats are too thin, and five is more than the minimum.2025 CRC R703.7.2

How far on center along framing may lath nails be spaced?

• a.Not more than 36 inches
• b.Not more than 24 inches
• c.Not more than 2 inches
• d.Not more than 7 inches✓

Lath fasteners are spaced not more than 7 inches on center along framing. Two inches is closer than needed, and 24 and 36 inches are the between-framing figure or farther than allowed.2025 CRC R703.7.1

What is the minimum net clear opening area of an upper-floor escape window?

• a.6.5 square feet
• b.5.0 square feet
• c.4.0 square feet
• d.5.7 square feet✓

An upper-floor escape opening needs 5.7 square feet net clear. Five square feet is the grade-floor figure, 4 square feet is too small, and 6.5 square feet is more than the minimum.2025 CRC R319.2.1

What are the minimum clear height and width of an escape opening?

• a.24 inches high and 20 inches wide✓
• b.18 inches high and 18 inches wide
• c.20 inches high and 24 inches wide
• d.36 inches high and 36 inches wide

The net clear height is 24 inches and the width is 20 inches. Reversing them, or using 36 by 36 or 18 by 18 inches, does not match the code.2025 CRC R319.2.2

What maximum height may the bottom of an escape opening be above the floor?

• a.24 inches
• b.48 inches
• c.36 inches
• d.44 inches✓

The bottom of the clear opening is not more than 44 inches above the floor. Thirty-six inches is lower than the limit, 48 inches is above it, and 24 inches is the minimum clear height of the opening itself.2025 CRC R319.2.3

A glass pane is located within 24 inches of a door with its bottom edge 36 inches above the floor. What does the CRC require?

• a.Standard glass, unless the pane is over 9 square feet
• b.Standard glass is acceptable
• c.Safety glazing✓
• d.Standard glass, since the pane edge is under 60 inches

Glazing within 24 inches of a door with its bottom edge under 60 inches above the floor is a hazardous location, so safety glazing is required. Standard glass fails, the 9-square-foot test belongs to large windows, and 60 inches is the upper limit for the bottom edge, not a minimum height.2025 CRC R324.4.2

How is a replacement window installed?

• a.With paint alone, sealing the joint at the trim
• b.With foam only, filling the gap around the frame
• c.Without flashing, since the frame seals itself
• d.In accordance with the maker's instructions✓

Windows and doors are installed per the manufacturer's written instructions and the opening is flashed per the CRC. A frame cannot seal itself, and foam only or paint alone leaves the opening unprotected from water.2025 CRC R609.1

A roof slope is 1.5:12. Can asphalt shingles be used?

• a.Yes, with double underlayment over the whole deck
• b.Yes, with one layer of underlayment over the deck
• c.Yes, with no underlayment
• d.No; it needs a slope of at least 2:12✓

Asphalt shingles need at least 2:12, so 1.5:12 is too flat whatever the underlayment. One layer, two layers or no underlayment do not fix an insufficient slope.2025 CRC R905.2.2

What metal flashing thickness does the CRC require?

• a.0.100 inch
• b.0.005 inch, about the thickness of foil
• c.Not less than 0.019 inch✓
• d.0.050 inch of galvanized sheet

Metal flashing is not less than 0.019 inch (No. 26 galvanized). Five thousandths is far too thin, and 0.050 and 0.100 inch are thicker than required.2025 CRC R903.2.1

Where must roof flashing be installed?

• a.Only at the ridge, where the two slopes meet
• b.Only around the chimney, the one large opening
• c.At wall intersections, slope changes and roof openings✓
• d.Only along the eaves, where water leaves the roof

Flashing goes at wall and roof intersections, slope changes and roof openings. Flashing only at the ridge, only along the eaves or only around the chimney leaves the other intersections unprotected.2025 CRC R903.2.1

An attic is 1,800 square feet. What net free ventilating area does the basic rule require?

• a.6 square feet
• b.18 square feet
• c.1.8 square feet
• d.12 square feet✓

1,800 ÷ 150 = 12 square feet. Six is the 1/300 figure, 18 is 1/100 and 1.8 is 1/1,000.2025 CRC R806.2

What size attic access opening is required for rough framing in a hallway ceiling?

• a.18 inches by 18 inches, with a pull-down cover
• b.12 inches by 12 inches, with no minimum height
• c.At least 22 inches by 30 inches✓
• d.36 inches by 48 inches, framed into the wall

The rough opening is at least 22 by 30 inches. Twelve by twelve and eighteen by eighteen are too small to enter, and 36 by 48 inches is larger than required.2025 CRC R807.1

When may a new roof covering go over the existing one instead of a tear-off?

• a.Always, since a recover is the usual method
• b.Only where the code's listed conditions are met✓
• c.Whenever the owner prefers a faster, cheaper job
• d.Never, because replacement is the only method

A recover is permitted only where one of the code's listed conditions occurs. It is not always permitted, since the code names conditions, it is not never permitted, since those conditions exist, and the owner's schedule or budget is not one of them.2025 CRC R908.4

Under Cal/OSHA's residential roofing rule, a 4:12 roof has an eave 8 feet above grade. Is fall protection required?

• a.No, because the eave is under 15 feet
• b.No, because the slope is gentle
• c.Yes, because the fall distance is 6 feet or more✓
• d.Yes, but above 20 feet

On slopes up to 7:12 the trigger is a fall distance of 6 feet or more above the grade or level below. Gentle slope and the 15- or 20-foot figures are not the trigger.8 CCR 1731(c)

Exterior wall water-resistive barrier must be continuous to what point?

• a.Not required
• b.Above windows
• c.The top of the wall✓
• d.The first floor

The barrier runs continuously to the top of the wall and terminates at penetrations. Only the first floor, only above windows or no barrier leaves water paths open.2025 CRC R703.2

How should overlapping flashings on exterior walls be applied?

• a.In shingle fashion✓
• b.Butted without overlap
• c.Randomly
• d.In reverse

Overlapping flashing is applied in shingle fashion so water sheds outward. Reverse laps, random laps and butted joints let water in.2025 CRC R703.4

What clearance does vinyl siding need from adjacent surfaces such as decks and roofs?

• a.At least 6 inches, the same as from the ground
• b.At least 2 feet of open air space
• c.At least 1/2 inch✓
• d.None, siding may touch them

Vinyl siding keeps 1/2 inch from adjacent surfaces like decks and roofs. Six inches is the ground clearance, two feet is not stated, and none would let it bind.2025 CRC R703.3.1

How long must each stucco coat remain moist before the next?

• a.At least 48 hours✓
• b.At least 14 days
• c.At least 1 hour
• d.At least 4 hours

Each coat stays moist at least 48 hours before the next. Four hours and one hour are too short, and 14 days is longer than required.2025 CRC R703.7.4

What is the maximum spacing for lath nails along framing?

• a.2 inches on center along the framing
• b.18 inches on center along the framing
• c.7 inches on center✓
• d.36 inches

Lath nails are at most 7 inches on center along framing. Two inches is closer than needed, and 18 and 36 inches are farther than allowed.2025 CRC R703.7.1

In a pre-1978 house, how far must ground plastic extend beyond exterior renovation surfaces?

• a.1 foot beyond the surfaces being renovated
• b.6 feet, the same as interior floors
• c.3 feet beyond the surfaces being renovated
• d.10 feet, or farther to catch debris✓

Ground plastic extends 10 feet, or farther to catch falling debris. One and three feet are too short, and 6 feet is the interior floor figure.40 CFR 745.85(a)(2)(ii)

Exterior work within 10 feet of a property line on a pre-1978 house requires what?

• a.Vertical containment or equivalent extra precautions✓
• b.A sign
• c.A fence or sign posted along the property line boundary
• d.Nothing

Vertical containment or equivalent extra precautions are required. Doing nothing, only a sign or only a fence does not keep dust and debris off adjacent property.40 CFR 745.85(a)(2)(ii)

A glass panel beside a door is 18 inches from the door and has its bottom edge 30 inches above the floor. What is it?

• a.Not hazardous, so any glass may be used
• b.Safety glazing is required✓
• c.Hazardous when the pane is above 9 square feet
• d.Hazardous when the glass is tinted

Glazing within 24 inches of a door with its bottom edge under 60 inches is hazardous and needs safety glazing. Tint is irrelevant, and the 9-square-foot test applies to large windows.2025 CRC R324.4.2

A large window pane is 12 square feet, with its bottom edge 10 inches above the floor, top edge 70 inches, and a walkway at the glass. What is it?

• a.A hazardous location needing safety glazing✓
• b.Not hazardous because it is a window and not a door
• c.Hazardous when the pane is under 9 square feet
• d.Hazardous when the window can be opened

A pane over 9 square feet with a bottom edge under 18 inches, a top edge over 36 inches and a walking surface within 36 inches is hazardous, whether or not the window opens, and a window is not exempt just because it is a window. The under-9-square-foot condition is not the test, since 12 square feet is over the size threshold.2025 CRC R324.4.3

What is the minimum area well size for a below-grade escape window?

• a.20 square feet
• b.9 square feet✓
• c.1 square foot
• d.4 square feet

The area well is at least 9 square feet with a horizontal projection and width of at least 36 inches. Four and one square foot are too small, and 20 square feet is more than the minimum.2025 CRC R319.4.1

What clear height does an egress door need?

• a.84 inches
• b.60 inches
• c.78 inches✓
• d.72 inches

The required egress door has at least 78 inches of clear height. Sixty and seventy-two inches are too low, and 84 inches is more than required.2025 CRC R318.2

An exterior landing at the required egress door has a floor 3 inches lower than the threshold, and the door swings over that landing. What is the finding?

• a.It is required
• b.It is acceptable if there is a door mat
• c.It is acceptable
• d.It is more than the 1-1/2 inch allowance✓

The landing or floor at the required egress door is not more than 1-1/2 inches lower than the top of the threshold, with an exception for the exterior side where the door does not swing over it. Here the door does swing over the landing, so the exception does not apply: a 3-inch drop exceeds the allowance, a door mat does not change the drop, and calling it acceptable ignores the limit.2025 CRC R318.3.1

A window opening bottom is 18 inches above the floor and more than 72 inches above grade. What does the CRC require?

• a.Nothing, since an operable window is itself an exit
• b.A 4-inch sphere limit or an ASTM F2090 device✓
• c.A 42-inch guard, since every window needs one
• d.A window screen rated to hold a person's weight

Where the opening is under 24 inches above the floor and over 72 inches above grade, windows limit passage of a 4-inch sphere or have a control device meeting ASTM F2090. A screen is not fall protection, the exit function does not waive the rule, and the code does not require a 42-inch guard at every window.2025 CRC R321.2.1