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

A bathroom toilet's centerline is 17 inches from the left wall and 13 inches from the tub on the right. What does the handout say?

• a.The right side is too tight; 15 inches✓
• b.The left side is too tight; 18 inches is required
• c.Both sides pass because the total is 30 inches
• d.The toilet must be 24 inches from each side

The handout requires 15 inches from the centerline to each side, so 13 inches fails even though the two sides total 30. Eighteen inches is not the figure, and 24 inches is the clear space in front.City of Rancho Cucamonga handout BSF-0031 (CPC 402.5 as cited)

What maximum mixed water temperature must a shower valve deliver per the bathroom handout?

• a.105 degrees Fahrenheit
• b.110 degrees Fahrenheit
• c.140 degrees Fahrenheit
• d.120 degrees Fahrenheit✓

Handle positions are set to a maximum mixed water temperature of 120 degrees. The 110-degree limit is for bidet discharge, and 105 and 140 are not the stated figures.City of Rancho Cucamonga handout BSF-0031 (CPC 408.4 as cited)

A water heater's relief valve is installed with a shutoff valve on its discharge pipe. What is the finding?

• a.Prohibited; no shutoff valve may be on the relief discharge✓
• b.Required to prevent leaks
• c.Acceptable if the valve is a gate valve
• d.Acceptable if the valve is brass

The code prohibits a shutoff valve between the relief valve and the heater or on discharge pipes between the valve and the atmosphere. Valve material or type does not matter, and the valve would defeat the safety device. A shutoff is not needed to prevent leaks, because the relief valve itself is the leak-stopping safety device.2025 CPC 504.6

A water heater is 40 inches tall. Where must the upper strap be placed?

• a.On the vent pipe
• b.Within the lower third, at least 4 inches above the controls
• c.In the top third, above about 26-2/3 inches from the floor✓
• d.Within 2 inches of the floor

Straps are placed within the upper and lower thirds of the vertical dimension; the upper third of a 40-inch tank starts at about 26.7 inches. Bottom-only, floor-level and vent-only restraint do not satisfy the rule.2025 CPC 507.2

A B-2 contractor is asked to replace a bathroom lavatory with a similar one, using existing supply and drain connections. How is this work classified?

• a.Asbestos work, which needs a C-22 license
• b.Fixture replacement, which is B-2 work✓
• c.Plumbing system work, which needs a plumbing license
• d.Structural work, which a B-2 contractor may not take

Installing, repairing or replacing plumbing fixtures such as faucets, sinks, toilets and tubs is B-2 work. A like-for-like swap does not install or extend a system, is not structural and has nothing to do with asbestos.Bus. & Prof. Code section 7057.5(b)(1)

How many 20-ampere small-appliance branch circuits are required for kitchen countertop and wall receptacles?

• a.At least two✓
• b.At least four
• c.Exactly one
• d.None, if the circuit is 15 amperes

The kitchen handout requires a minimum of two 20-ampere small-appliance circuits. One is fewer than the minimum, four is more than required, and 15-ampere circuits are not the stated size.City of Rancho Cucamonga handout BSF-0030 (CEC 210.11(C) as cited)

Which statement about kitchen countertop receptacle spacing is correct?

• a.No point on the wall line is over 24 inches from one✓
• b.Receptacles are required every 8 feet
• c.Receptacles must be spaced exactly 12 inches apart along the wall
• d.Receptacles are required over the sink

The handout says no point along the wall line is more than 24 inches from a receptacle. Twelve inches is the minimum space width, and 8-foot spacing or sink-only placement are not stated.City of Rancho Cucamonga handout BSF-0030 (CEC 210.52 as cited)

A bathroom receptacle is planned inside the shower zone. What is the finding?

• a.Allowed if the receptacle is tamper-resistant
• b.Allowed if the receptacle is GFCI protected
• c.Allowed if mounted above 6 feet high
• d.Prohibited in the tub or shower zone✓

Receptacles are not installed within 8 feet above the tub rim or shower threshold and within 3 feet of the tub or shower perimeter. GFCI protection, tamper resistance and height do not make the zone acceptable.City of Rancho Cucamonga handout BSF-0031 (CEC 406.9(C) as cited)

Smoke alarms are required where in a dwelling unit under CRC R310.3?

• a.In the garage, close to the parked vehicles
• b.In each sleeping room and outside sleeping areas✓
• c.On the roof
• d.In the kitchen, close to the cooking appliances

Alarms go in each sleeping room, outside each separate sleeping area, and on each additional story including basements and habitable attics. Kitchen-only, garage-only and roof placement are not the rule.2025 CRC R310.3

A B-2 contractor is asked to add a new 20-ampere circuit from the panel to a laundry room. How is this work classified?

• a.A fixture replacement within the B-2 license
• b.A finish carpentry task
• c.A permit-exempt task
• d.Electrical system work✓

Installing or extending electrical systems is outside B-2 unless performed by a properly licensed subcontractor. A new circuit is not a fixture swap, finish carpentry or permit-exempt work.Bus. & Prof. Code section 7057.5(c)(3)

Each bathroom with a bathtub or shower must be ventilated how?

• a.By a ceiling fan
• b.By an operable window alone, opened during every shower
• c.By an open door
• d.By a mechanical exhaust fan; a window does not count✓

The CRC requires mechanical ventilation for humidity control and notes that window operation is not a permissible method. A ceiling fan or an open door does not exhaust to the outdoors.2025 CRC R325.2.1

What is the minimum continuous-ventilation exhaust rate for a bathroom?

• a.100 cubic feet per minute
• b.5 cubic feet per minute
• c.50 cubic feet per minute
• d.20 cubic feet per minute✓

The CRC gives 20 cfm for continuous and 50 cfm for intermittent operation. Five cfm is too low, and 100 cfm is the kitchen hood figure in the handout.2025 CRC R325.2

What does the kitchen handout say about range hood ducts?

• a.Any plastic duct pipe may be used if it is labeled as heat rated
• b.The duct may end inside the attic space directly above the kitchen
• c.Metal with smooth interiors; aluminum flex duct is prohibited✓
• d.The hood may simply recirculate its air back into the kitchen room

Range hood ducts are metal with smooth interiors, and the handout prohibits aluminum flex duct. Plastic is not an allowed duct material, a hood may not recirculate into the room because kitchen exhaust goes outdoors, and ending a duct in the attic would discharge moisture and grease into the building.City of Rancho Cucamonga handout BSF-0030 (CMC 504 as cited)

A 2x4 stud in a bearing partition (3-1/2 inches deep) is notched for a pipe. What is the maximum notch depth?

• a.1-3/4 inches
• b.7/8 inch✓
• c.1-3/8 inches
• d.2-1/10 inches

Bearing studs may be notched to 25 percent of depth: 3.5 × 0.25 = 0.875 inch, or 7/8 inch. The 1.4-inch figure is the nonbearing 40 percent limit, 1-3/4 is half and 2.1 inches is 60 percent.2025 CRC R602.6

Where must fireblocking be provided in a stud wall?

• a.At floor and ceiling levels and every 10 feet horizontally✓
• b.At the roof line and along the top plate of every wall
• c.At windows
• d.Nowhere in remodels

Fireblocking goes vertically at ceiling and floor levels and horizontally at intervals not over 10 feet, with additional locations at soffits, stair stringers and penetrations. A single roof location, window-only locations or no fireblocking in remodels would all leave concealed draft openings.2025 CRC R302.11

What protection is required inside a closet formed under a stair?

• a.None, since a closet is not a habitable room
• b.1/2-inch gypsum board on the enclosed side✓
• c.1/4-inch hardboard on the enclosed side
• d.Paint or a clear sealer on the framing

Enclosed space under stairs reached by a door or panel has walls, soffits and underside protected with 1/2-inch gypsum board. Paint and thin hardboard do not provide it, and a closet under a stair is still enclosed usable space, so some protection is required.2025 CRC R302.7

What is the maximum depth of a notch in a 2x8 floor joist (7-1/4 inches deep) away from the ends?

• a.About 0.5 inches
• b.About 1.2 inches✓
• c.About 2.4 inches
• d.About 3.6 inches

Notches in joists may not exceed one-sixth of the depth: 7.25 ÷ 6 = 1.21 inches, and not in the middle third of the span. Two-point-four is one-third, 3.6 is half and 0.5 is not the limit.2025 CRC R502.8.1

Where is Type X board called for in the CRC gypsum table?

• a.Behind kitchen cabinets
• b.On every closet wall and on every bedroom wall
• c.On exterior walls
• d.On a garage ceiling beneath habitable rooms✓

The table lists 5/8-inch Type X for a garage ceiling beneath habitable rooms. Closet walls and the backs of kitchen cabinets are not listed uses, and exterior walls follow the sheathing and covering provisions rather than the Type X garage entry.2025 CRC Table R702.3.5

Which board may be used as a tile backer in a shower?

• a.Particleboard
• b.Standard paper-faced gypsum board
• c.Hardboard
• d.Glass mat gypsum✓

The CRC lists glass mat gypsum, fiber-reinforced gypsum, fiber-cement and fiber-mat cementitious backers for tub and shower areas. Ordinary board, hardboard and particleboard are not on the list, and standard board is not installed where exposed to water.2025 CRC R702.4.2

What is the maximum riser height on a residential stair?

• a.6 inches
• b.9 inches
• c.8-1/4 inches
• d.7-3/4 inches✓

Risers may not exceed 7-3/4 inches. Eight and a quarter and nine inches are over the maximum, and 6 inches is within it but is not the stated limit, so it cannot be the maximum. The same flight may vary by no more than 3/8 inch.2025 CRC R318.7.5.1

What is the minimum tread depth?

• a.10 inches✓
• b.8 inches
• c.9 inches
• d.12 inches

Tread depth is not less than 10 inches. Eight and nine inches are too shallow for the code, and 12 inches is more than the minimum. A nosing projection is not required once a tread reaches 11 inches.2025 CRC R318.7.5.2

A stair has a handrail at 41 inches. What is the finding?

• a.It meets the code
• b.It is above the 38-inch maximum✓
• c.It is below the 34-inch minimum
• d.It is exactly 36 inches

Handrail height is measured from the nosing line and must be between 34 and 38 inches, so 41 inches is above the maximum. It does not meet the code, it is not below the 34-inch minimum, and 36 inches is a different number from the one given.2025 CRC R320.2

Which tile mortar coverage does ANSI A108 call for in a wet area?

• a.65 percent
• b.95 percent✓
• c.80 percent
• d.50 percent

Wet and exterior areas require 95 percent mortar coverage for ceramic and porcelain tile. Fifty and sixty-five percent are not the published requirement, and 80 percent is the dry-area figure that is easy to confuse with it.ANSI A108 requirement as stated by the Ceramic Tile Foundation

Two flooring makers publish different expansion gaps. What governs?

• a.Whatever gap was used on the previous flooring job
• b.The instructions for the product being installed✓
• c.The smaller gap of the two, used for every product
• d.The larger gap of the two, used for every product

Each maker's instructions control its own product, so the installer follows the instructions for the floor being laid. Always using the larger gap, always using the smaller gap, or repeating the gap from the last job each ignore that the makers differ.Manufacturer installation guides (engineered hardwood)

What is the maximum slope of the walking surface of a stair tread or landing?

• a.1 in 4
• b.1 in 12
• c.1 unit vertical in 20 units horizontal in all cases
• d.1 unit vertical in 48 units horizontal✓

Walking surfaces are sloped not steeper than 1:48 (2 percent), with a 1:20 allowance only where a landing must drain water. One in twelve and one in four are far too steep, and 1:20 applies only where a landing must drain water, not in all cases.2025 CRC R318.7.7

Which statement describes the clear space required for a toilet according to the bathroom handout?

• a.30 inches total with 15 each side, and 24 in front✓
• b.36 inches wide in total and 36 inches in front
• c.24 inches wide in total with 12 each side, and 30 in front
• d.15 inches wide in total with 7-1/2 each side, and 15 in front

The handout requires a total of 30 inches (15 from the centerline to each side) and 24 inches in front. The other pairings reverse the figures, use the shared 15 as the total or give numbers that are not stated.City of Rancho Cucamonga handout BSF-0031 (CPC 402.5 as cited)

Which devices must a shower valve be, according to the bathroom handout?

• a.Ball valves without mixing
• b.Gate valves
• c.Single-handle compression valves
• d.Pressure-balance✓

The handout requires individual control valves of the pressure-balance, thermostatic or combination type, with the handle positions adjusted to a 120-degree maximum mixed setting. Compression, gate and plain ball valves do not control scalding.City of Rancho Cucamonga handout BSF-0031 (CPC 408.4 as cited)

A faucet with two handles is replaced. Which handle goes on the left according to the handout?

• a.Neither; both on the right
• b.Either, by preference
• c.Hot✓
• d.Cold

The hot water valve goes on the left. Cold on the left reverses the rule, personal preference is not allowed, and putting both on the right contradicts it.City of Rancho Cucamonga handout BSF-0031 (CPC 417.5 as cited)

A site-built shower stall is 28 inches by 34 inches inside. What is the finding?

• a.It exceeds the minimum, so the stall can be built as drawn
• b.It needs a 20-inch circle
• c.It meets the minimum, so the stall can be built as drawn
• d.Its area, 952 square inches, is under the minimum✓

The stall area is 28 × 34 = 952 square inches, under the 1,024 minimum, and it must also encompass a 30-inch circle. The other findings misread the area or the circle.City of Rancho Cucamonga handout BSF-0031 (CPC 408.7 as cited)

A bidet is added to a bathroom. What protection does the handout require for its supply?

• a.A single check valve on the supply line
• b.An air gap or vacuum breaker✓
• c.Nothing, since bidets use clean water
• d.A shutoff valve at the fixture alone

The bidet supply is protected by an air gap or vacuum breaker, and its hot water discharge is limited to 110 degrees. A shutoff or check valve alone is not the protection.City of Rancho Cucamonga handout BSF-0031 (CPC 410.2 as cited)

Which statement about the relief valve discharge capacity is correct?

• a.Not less than the water heater's input rating✓
• b.Half the input rating of the water heater unit
• c.Equal to the volume of the storage tank itself
• d.Unrelated to the heater's input rating in any way

The device's discharge capacity must be not less than the input rating of the water heater. Half the rating, no relation and tank volume are not the rule.2025 CPC 504.6

A water heater's lower strap is 3 inches above its controls. What is the finding?

• a.It must be at the controls
• b.It meets the rule
• c.It must be 12 inches above the controls
• d.It must be 4 inches above the controls✓

At the lower strap point at least 4 inches must be maintained above the controls. Three inches is too close, strapping at the controls is not allowed, and 12 inches is not required.2025 CPC 507.2

A kitchen island sink needs venting. What does the handout describe?

• a.A high vent that returns down to the sink drain✓
• b.The sink is unvented, as islands cannot be vented
• c.The vent runs through the floor, below the sink trap
• d.A cleanout replaces the vent

For island sinks the trap is roughed in above the floor and vented by extending the vent as high as possible, not less than the drain board height, then returning downward to the horizontal drain. Unvented sinks and cleanouts do not vent.City of Rancho Cucamonga handout BSF-0030 (CPC 909 as cited)

A kitchen has a 9-foot wall countertop with no breaks. By the 24-inch rule, what is the minimum number of countertop receptacles on that wall?

• a.Three✓
• b.Two
• c.Four
• d.Five

With end receptacles within 24 inches of the ends and spacing at most 48 inches, 108 − 48 = 60 inches between end receptacles needs one more, for three. Two leaves a 60-inch gap, and four or five exceed the minimum.City of Rancho Cucamonga handout BSF-0030 (CEC 210.52 as cited)

Which statement describes receptacles within 6 feet of a kitchen sink?

• a.They are GFCI protected and tamper-resistant✓
• b.They are exempt from GFCI protection near the sink
• c.They need AFCI
• d.They must be above 48 inches

The handout requires GFCI and tamper-resistant protection within 6 feet of the sink's outside edge. AFCI alone does not replace GFCI, and the height rule is a 20-inch maximum above the counter.City of Rancho Cucamonga handout BSF-0030 (CEC 210.8 as cited)

A kitchen island is 30 inches by 48 inches. What receptacle rule applies?

• a.None, because islands cannot have receptacles
• b.One receptacle, no more than 12 inches below the top✓
• c.One receptacle, mounted 30 inches above the counter
• d.One floor box receptacle under the island

Islands and peninsulas of at least 24 by 12 inches need at least one receptacle mounted not more than 12 inches below the countertop, where the top does not extend more than 6 inches beyond its support. Islands are not exempt from receptacles, a receptacle 30 inches above the counter is far above the allowed mounting height, and a floor box is not the handout's way to serve an island.City of Rancho Cucamonga handout BSF-0030 (CEC 210.52 as cited)

What does the handout say about a cord-and-plug range hood?

• a.It needs a dedicated circuit✓
• b.It shares the small-appliance circuit
• c.It is wired to the lighting circuit
• d.It needs no circuit

A cord-and-plug range hood needs a dedicated circuit. Sharing the small-appliance circuit, using no circuit and tying it to lighting are not what the handout allows.City of Rancho Cucamonga handout BSF-0030 (CEC 422.16 as cited)

What must be true of bathroom receptacles near a basin?

• a.A 20-ampere GFCI receptacle within 36 inches of the basin✓
• b.A receptacle in the tub zone
• c.A 15-ampere receptacle located about 6 feet from the basin
• d.Any receptacle in the hallway outside the bathroom door, if grounded

The handout requires a 20-ampere GFCI-protected receptacle within 36 inches of the outside edge of each basin. A distant 15-ampere receptacle, a hallway receptacle and a tub-zone receptacle do not meet it.City of Rancho Cucamonga handout BSF-0031 (CEC 210.52(D) as cited)

Luminaires within the actual dimensions of the tub or shower must be what, per the handout?

• a.Open-bulb fixtures
• b.Painted white
• c.Enclosed✓
• d.Any pendant fixture

The handout requires enclosed and gasketed fixtures listed for damp or wet locations and GFCI protected. Open bulbs and pendants are not suitable, and color is irrelevant.City of Rancho Cucamonga handout BSF-0031 (CEC 410.10 as cited)

A permitted alteration occurs in a house. What does CRC R310.2.2 require?

• a.Smoke alarms in the attached garage and shop
• b.Smoke alarms as required for new dwellings✓
• c.Smoke alarms in the kitchen and the dining room
• d.Nothing at all, because the work is a remodel

Where alterations requiring a permit occur, the dwelling unit is equipped with smoke alarms located as for new dwellings. Alarms in only the garage and shop, or only the kitchen and dining room, do not follow the locations for new dwellings, and a remodel does not waive the requirement.2025 CRC R310.2.2

Which room-lighting statement matches the kitchen handout?

• a.Cabinet lighting is on the same switch as the ceiling
• b.Recessed lights need not be IC rated
• c.Installed luminaires are high efficacy✓
• d.Incandescent bulbs are required

The kitchen handout calls for high-efficacy luminaires and separate switching for cabinet lighting. Sharing a switch with the ceiling, using non-IC recessed fixtures and requiring incandescent bulbs all contradict it.City of Rancho Cucamonga handout BSF-0030 (CEnC 150.0(k) as cited)

What is the minimum exhaust rate for an intermittent bathroom fan?

• a.100 cubic feet per minute
• b.50 cubic feet per minute✓
• c.10 cubic feet per minute
• d.20 cubic feet per minute

The minimum exhaust rate for an intermittent bathroom fan is 50 cfm in the CRC. Twenty is the continuous figure, 100 cfm is the kitchen hood figure, and 10 cfm is below both.2025 CRC R325.2

Where may a bathroom fan duct end according to the bathroom handout?

• a.Outdoors, at least 3 feet✓
• b.Into the attic, above the insulation
• c.In the crawl space
• d.Under the eave without a duct

A bathroom fan duct ends outdoors, at least 3 feet from a property line, 10 feet from forced-air inlets and 3 feet from building openings, not onto a public walkway. The attic, a crawl space or a spot under the eave without a duct all discharge moist air into the building, where it causes mold and rot.City of Rancho Cucamonga handout BSF-0031 (CMC 504.1 as cited)

A bathroom fan is controlled by what, according to the handout?

• a.An accessible humidistat adjustable from 50 to 80 percent✓
• b.A timer that the homeowner must reset by hand every morning
• c.No control
• d.A wall switch locked permanently in the on position at all times

The handout requires a readily accessible humidistat adjustable from 50 to 80 percent relative humidity. A timer alone, a locked switch and no control do not meet it.City of Rancho Cucamonga handout BSF-0031 (CEnC 150(o) as cited)

A habitable room has 200 square feet of floor area. What openable area satisfies natural ventilation?

• a.20 square feet
• b.4 square feet
• c.8 square feet✓
• d.12 square feet

Openable area is not less than 4 percent of floor area: 200 × 0.04 = 8. Four is too low and 12 and 20 are more than needed.2025 CRC R325.1.2

A toilet room with no tub or shower has only a window. What does the CRC require for glazing?

• a.No window or fan
• b.At least 3 square feet✓
• c.At least 10 square feet
• d.At least 1 square foot

Such a room needs at least 3 square feet of glazing, half of it openable, unless light and local exhaust are provided. One square foot is too small, 10 square feet is more than required, and having no window or fan fails the rule.2025 CRC R325.2

Where is a mechanical exhaust fan required in a dwelling bathroom?

• a.In the garage, near the parked vehicles
• b.In the kitchen, above the cooking range
• c.In a half-bath with no tub or shower
• d.In a bathroom containing a tub or shower✓

A fan is required in a bathroom with a tub or shower. A kitchen-only, half-bath-only or garage-only requirement is not what the CRC says.2025 CRC R325.2.1

An outdoor air intake is planned next to a plumbing vent. What does the CRC say?

• a.Right at the vent, to draw the freshest air
• b.At least 10 feet from vents, unless 3 feet below them✓
• c.At least 3 feet from vents in every case
• d.At least 100 feet from any plumbing vent

Intake openings are not less than 10 feet from hazardous or noxious contaminants such as vents, chimneys and plumbing vents, unless the intake is 3 feet or more below the source. Three feet applies only to that below-the-source exception, placing the intake at the vent draws in contaminants, and 100 feet is far beyond any figure the code gives.2025 CRC R325.4.1

Which top-plate cut in a load-bearing wall requires a metal tie?

• a.A cut of more than 50 percent of the plate's width✓
• b.A cut of 10 percent of the width of the plate or less
• c.Any cut at all
• d.A cut of 25 percent

When cutting, drilling or notching exceeds 50 percent of the plate's width in an exterior or bearing wall, a metal tie is installed. Cuts of 10 percent or 25 percent do not exceed the 50 percent limit, and a tie is not needed for every cut.2025 CRC R602.6.1

Notches in a 2x12 joist (11-1/4 inches deep) away from the ends may be at most how deep?

• a.About 5.6 inches
• b.About 3.75 inches
• c.About 2.8 inches
• d.About 1.9 inches✓

Joist notches are limited to one-sixth of the depth: 11.25 ÷ 6 = 1.875 inches. The other values are one-third, one-half and one-quarter of the depth.2025 CRC R502.8.1