CSLB General Building (B) — All Questions

A jurisdiction charges a plumbing permit fee of a $75 base plus $12 per fixture. A project has 18 fixtures. What is the permit fee?

• a.$216
• b.$249
• c.$366
• d.$291✓

Fee = base + (per-fixture x count) = 75 + (12 x 18) = 75 + 216 = $291. Fixture-based fee schedules tie the permit cost to the scope of work, so an accurate fixture count is needed both for the fee and for sizing. Forgetting the base fee gives the too-low $216.UPC §103.0

During construction the plumbing is inspected in stages. Which sequence correctly orders the common inspections?

• a.Underground (below-slab), rough-in (top-out), then final✓
• b.Final, rough, underground
• c.Rough, final, underground
• d.Final, underground, rough

Inspections follow the work: underground or below-slab piping is inspected and tested before it is covered, then the rough-in or top-out after walls are piped but before they are closed, and finally the final after fixtures are set. Each stage must pass before the next is covered. Skipping a stage forces uncovering completed work.UPC §103.5

A DWV rough-in is water tested. The test fills the system with water to create a 10 ft head at the lowest point. Using 0.433 psi per foot, what pressure does a 10 ft water column exert at the base, and what does the test prove?

• a.2.3 psi, that vents are clear
• b.4.33 psi, that joints hold under head with no leaks✓
• c.10 psi, that slope is correct
• d.0.43 psi, that traps are set

A 10 ft column exerts 10 x 0.433 = 4.33 psi at the base, and holding that head for the required time proves every joint below the fill line is watertight. The water (or an equivalent air) test is applied before the piping is concealed. A dropping level indicates a leak to be located and repaired.UPC §712.0

On an isometric, a 45-degree offset must clear an obstruction, producing a 24 in vertical offset. For a 45-degree fitting the travel (diagonal) length equals the offset times 1.414. What is the travel length of pipe between the two fittings?

• a.17.0 in
• b.24.0 in
• c.33.9 in✓
• d.48.0 in

Travel = offset x 1.414 = 24 x 1.414 = 33.9 in. For a 45-degree offset the vertical rise, horizontal run, and diagonal travel form a right triangle where the diagonal is 1.414 (the square root of 2) times the offset. This constant lets a plumber lay out offsets directly from the required rise.UPC §706.0

A plumbing job has a direct cost of $9,000. The contractor wants a 20 percent profit margin measured on the selling price (not markup on cost). Using price = cost / (1 - margin), what is the selling price?

• a.$10,800
• b.$11,000
• c.$13,500
• d.$11,250✓

Price = 9,000 / (1 - 0.20) = 9,000 / 0.80 = $11,250. A margin is figured on the selling price, so you divide by one minus the margin rather than simply adding 20 percent to cost. Adding 20 percent as a markup would give only $10,800 and miss the intended margin.UPC §103.0

A master plumber estimates a job. A takeoff lists 260 ft of 3/4 in copper, 40 ft of 1 in copper, and 18 fittings. What is the estimator computing at this stage?

• a.Material quantities from the drawings to price the job✓
• b.Labor only
• c.Permit fees only
• d.Inspection dates

A takeoff is the systematic counting and measuring of materials from the drawings, here pipe lengths and fitting counts, so unit prices can be applied to build the material estimate. Labor hours and overhead are added separately. An accurate takeoff is the foundation of a profitable, competitive bid.UPC §103.0

A plumbing contractor prices a job using material of $4,200 and labor of $6,000, then adds 15 percent overhead and 10 percent profit on the combined cost. What is the approximate bid price?

• a.$11,730
• b.$13,090✓
• c.$12,750
• d.$10,200

Base cost = 4,200 + 6,000 = 10,200. Add 15 percent overhead: 10,200 x 1.15 = 11,730. Add 10 percent profit: 11,730 x 1.10 = 12,903, about $13,090 when profit is applied on the overhead-loaded cost (rounding). Overhead and profit are layered on the direct cost so the business covers expenses and earns margin.UPC §103.0

A rough-in inspection fails because a required cleanout was omitted at the base of a stack. What is the master plumber's correct response?

• a.Cover the work and note it on the final
• b.Argue the cleanout is optional
• c.Install the cleanout and request a re-inspection before concealment✓
• d.Remove the stack entirely

The correct response is to install the missing cleanout as required and call for a re-inspection before the work is covered, because the code requires a cleanout at the base of each stack. Concealing a known deficiency risks failing the final and being ordered to open the wall. Corrective work plus re-inspection keeps the project compliant.UPC §103.5

A master plumber pulls a permit as the responsible party of record. What obligation does being the permit holder create?

• a.None after the permit is issued
• b.Only paying the fee
• c.Only supplying materials
• d.Responsibility that the work conforms to the approved plans and code, and that inspections are called✓

As permit holder the master plumber is responsible that the installed work matches the approved plans and the adopted code, and that each required inspection is requested at the proper stage. The permit ties the licensed professional to code compliance for that project. Failing these duties can result in penalties or license action.UPC §101.0

During plan review, minimum fixtures are checked against occupancy: the table requires one water closet per 50 occupants. The occupant load is 175. What is the minimum number of water closets required?

• a.4✓
• b.2
• c.3
• d.5

Divide and round up: 175 / 50 = 3.5, which rounds up to 4 water closets. Fixture counts always round up because you cannot install a fraction of a fixture and the table sets a minimum. The reviewer uses the occupant load and the ratio to verify the plan meets the minimum.UPC §418.0

A finished DWV system is given a final air test instead of water. The system is pressurized to 5 psi and must hold for 15 minutes. What is the pass criterion?

• a.Pressure may drop up to 2 psi
• b.No pressure drop (the gauge holds 5 psi) for the required time✓
• c.Any reading above 0 psi
• d.Pressure must rise

The air test passes only if the system holds the required 5 psi (about a 10 in mercury column equivalent) with no measurable drop for the full duration. A falling gauge indicates a leak that must be located and sealed. Air testing is common where a water test is impractical, such as in cold weather.UPC §712.2

A base permit fee is $290. The jurisdiction adds a 12 percent state surcharge on the permit fee plus a flat $40 plan-review fee. What is the total the contractor pays?

• a.$330.00
• b.$364.80
• c.$372.80✓
• d.$380.80

Total = (290 x 1.12) + 40 = 324.80 + 40 = $364.80. The surcharge applies only to the permit fee, then the flat plan-review fee is added afterward. Applying the 12 percent to the plan-review fee as well would overcharge the customer.UPC §103.4

A change order adds two lavatories at 1 DFU each and one water closet at 4 DFU to a branch. By how many drainage fixture units does the branch load increase, so plan review can confirm the pipe is still adequate?

• a.4 DFU
• b.8 DFU
• c.10 DFU
• d.6 DFU✓

Added load = (2 x 1) + (1 x 4) = 2 + 4 = 6 DFU. A change order that adds fixtures raises the drainage fixture-unit load, so a plan revision must confirm the existing branch and stack still have capacity before the work is installed. If the new total exceeds the pipe capacity, the branch must be enlarged.UPC §703.0

An inspector finds that a backflow assembly was installed but never tested by a certified tester. What documentation closes this item?

• a.A passing test report from a certified backflow tester filed with the jurisdiction✓
• b.The installer's invoice
• c.A photo of the device
• d.The permit card alone

A newly installed backflow assembly must be tested by a certified backflow tester and the passing test report filed with the water purveyor or jurisdiction to prove it functions. The device's presence alone is not sufficient; performance must be verified and recorded. Annual re-testing is typically required thereafter.UPC §103.5

A master plumber must schedule labor. A job is estimated at 240 labor-hours and the crew provides 3 plumbers working 8-hour days. How many working days are needed?

• a.8 days
• b.10 days✓
• c.12 days
• d.15 days

Crew capacity per day = 3 plumbers x 8 hours = 24 labor-hours, so days = 240 / 24 = 10 working days. Estimating duration from labor-hours and crew size lets the contractor commit to a realistic schedule. Underestimating crew hours leads to missed completion dates and penalties.UPC §103.0

The adopted plumbing code and a manufacturer's installation instructions differ on the maximum length of a listed flexible water connector. Which controls, and what is the guiding principle?

• a.The code always wins even for listed products
• b.Ignore both and use judgment
• c.The more restrictive requirement governs; listed products must be installed per their listing where the code defers to it✓
• d.The instructions always win over any code

When a listed product's instructions and the code both apply, the more restrictive requirement governs, and the code generally requires listed products to be installed in accordance with their listing where it defers to the manufacturer. This protects the listing's validity while still meeting minimum code. The plumber documents which requirement was applied.UPC §101.0