Learning Hub Lesson Previews
The Learning Hub turns hard exam topics into short guided lessons with a diagram, a worked example and a quick check. Browse the lesson outlines and diagrams by trade here; the full lessons open inside the classroom. New previews are added every day.
Asbestos Certification (ASB)
Free preview: Asbestos Certification (ASB)
- Who Needs the ASB Certification and DOSH Registration: The 100 Square Foot Line
- Exposure Assessment and Monitoring: PELs, the Initial Assessment, and the Negative Exposure Assessment
- Class I to IV Asbestos Work, Training Hours, and the Competent Person
- Medical Surveillance and Recordkeeping: The 30-Day Trigger and How Long to Keep Records
- Asbestos Consultants and Site Surveillance Technicians: What a Contractor May and May Not Do
- Finding the ACM: the PACM Presumption, the Building Survey, and Sampling Counts
Boiler and Steam Fitting (C-4)
Free preview: Boiler and Steam Fitting (C-4)
- Sizing a Closed Expansion Tank by CMC Section 1004.4
- Boiler Group and Required Controls (CMC Table 1003.2.1)
- Combustion Air for a Boiler Room (CMC Chapter 7)
- Hydronic Test Pressure and Relief Valve Discharge (CMC 1205.2, 1206.2)
- Hydronic and Steam Pipe Insulation (Energy Code Table 120.3-A-1)
- Boiler Energy Code Rules: Input Size and Return Water Temperature
- Entering a Boiler: Isolation, Blinding and Double Block and Bleed (8 CCR 3312)
Framing and Rough Carpentry (C-5)
Free preview: Framing and Rough Carpentry (C-5)
- Notching and Boring Limits for Joists, Rafters, and Studs
- Floor Joist Deflection: The L/360 Limit and the Span Table
- Sill Plate Anchor Bolts: Spacing, End Distance, and Counting
- Deck Ledger Fastening: Lag Screw Spacing and Lateral Ties
- Shear Wall Fastening: Edge and Field Spacing, Fastener Counts, and 3x Framing
Cabinet and Finish Carpentry (C-6)
Free preview: Cabinet and Finish Carpentry (C-6)
- Crown Molding: Spring Angle and Compound Miter Settings
- Stair Layout: Rise, Run, and Baluster Spacing
- Doors: Clear Width, Clear Height, and Hardware Checks
- Accessible Sink Cabinets: Counter Height and Knee Clearance
- Accessible Kitchens: Aisle Clearances and Work Surface
- Cabinet Materials: Formaldehyde and VOC Limits
Concrete (C-8)
- Reading a Rebar Callout
- Sizing a Footing from the CRC Tables
- Specified Strength and Air Entrainment by Exposure
- Slab-on-Ground: Thickness, Base, Vapor Retarder and Capillary Break
- When Concrete Work Needs Special Inspection (CBC Table 1705.3)
- Caltrans Concrete: Slump Limits, Free Water and Delivery Time
- Caltrans Concrete Curing Methods and Periods
Earthwork and Paving (C-12)
Free preview: Earthwork and Paving (C-12)
- Hot Mix Asphalt Tonnage and the Spread-Rate Check
- Relative Compaction: Reading a Nuclear-Gauge Density Test
- Balancing Cut and Fill: Bank, Loose, and Compacted Yards
- Aggregate Base: Tons to Order, Lifts, and Grade Tolerance
- Matching Paver Speed to Plant Output and Truck Count
- Tack Coat: Residual Rate, Spray Rate, and Dilution
Fencing (C-13)
- Before You Dig Post Holes: The 811 Ticket and Marking Rules
- Chain-Link Post Footings: Caltrans Standard Plan A85
- Post Embedment Depth: CBC Equation 18-1 and Table 1806.2
- Chain-Link Takeoff: Posts, Braces, Fabric, and Fasteners
- Gates: Gate Posts, Width Limits, and California Building Code Gate Rules
- Pool Barrier Fence and Gate Rules (HSC §115923, 2025 CRC Appendix CI)
Flooring (C-15)
- Slab Moisture: Vapor Retarder and Capillary Break Under the Slab
- Subfloor Panels and Underlayment: Spans, Edge Support, and Particleboard
- Dust Control When Grinding Floors: 8 CCR 1532.3 Table 1
- CALGreen Flooring Products: Adhesive VOC Limits and the 80% Rule
- Floor Finish Fire Class: Radiant Flux Classes and Where They Apply
- Floor Transitions: Changes in Level, Thresholds, and Carpet Edges
- Carpet Layout: Breadths, Seams, and Pattern Repeat
Fire Protection (C-16)
Free preview: Fire Protection (C-16)
- Where Sprinklers Are Required: CFC 903.2 Triggers
- Required Fire Flow: California Fire Code Appendix B
- Hydrant Count and Spacing: California Fire Code Appendix C
- Standpipe Hose Connections and Fire Department Connections
- Fire Pump Room Requirements: CFC and CBC Section 913
- California Amendments to NFPA 13 and NFPA 24 (CFC Chapter 80)
HVAC (C-20)
- Airflow per Ton and Fan Efficacy: The Title 24 Verification Numbers
- Return Duct and Filter Sizing: Tables 150.0-B and 150.0-C, Equation 150.0-A
- Duct Leakage Targets: New Dwellings, Changeouts, and CMC Testing
- Condensate Drains: Pipe Size, Slope, and Overflow Protection
- Combustion Air for Furnaces in a Confined Space
- Whole-Dwelling Ventilation Rate (Energy Code Equation 150.0-B)
Building Moving and Demolition (C-21)
Free preview: Building Moving and Demolition (C-21)
- Estimating the Weight of a House You Are Going to Move
- Jacks, Cribbing, and Ground Bearing Under a Lifted House
- House Moves: Height, Width, and Route Clearance
- Demolition Order of Work: Survey, Utilities, Sequence, and the 25 Percent Rule
- Protecting the Public and Workers Below: Table 3306.1, Canopies, and Drop Zones
- Demolition Debris: Tons, the 65 Percent Diversion Rule, and Truckloads
Asbestos Abatement (C-22)
Free preview: Asbestos Abatement (C-22)
- Sizing Negative Air Units: Enclosure Volume, ACH, and CFM
- Air Sampling Math: Turning a PCM Fiber Count Into Fibers per cc
- Respirator Selection: Class of Work, Exposure Level, and Maximum Use Concentration
- Regulated Area Set-Up: Barriers, Signs, and the 25 Linear / 10 Square Foot Decon Trigger
- Glovebag Removal on Pipe Insulation and Bagging the Waste
Ornamental Metal (C-23)
Free preview: Ornamental Metal (C-23)
- Stair Stringer Layout: Riser Count, Tread Run, and Uniformity
- Guard Height and Baluster Spacing: The 4-Inch Sphere
- Handrail Profile, Clearance, and Extensions
- Accessible Ramp Rails: Rise, Landings, Extensions, and Edge Protection
- Guard and Handrail Loads: 200 lb, 50 plf, and the Post Base
- Caltrans Railing Steel: Galvanizing Schedule, Coating Check, and Tubular-Rail Fit
Landscaping (C-27)
Free preview: Landscaping (C-27)
- Landscape Water Budget: MAWA vs. ETWU
- Soil Prep Takeoff: Compost and Mulch Quantities (MWELO)
- Irrigation Design Checks: Setbacks, Narrow Strips, Slopes, and Meters
- Backflow Protection for an Irrigation Supply (CPC Sec. 603)
- Retaining Walls: The 4-Foot Permit Line and the 1.5 Safety Factor
- Tree Work Near Power Lines: The 10-Foot Rule and Who May Cross It
- Felling Cuts: Notch Depth, Back Cut, and Elevated-Work Rules
Lock and Security Equipment (C-28)
Free preview: Lock and Security Equipment (C-28)
- Panic and Fire Exit Hardware: Where It Is Required and How to Size It
- Bolts on the Inactive Leaf of a Pair of Doors (Table 1010.2.4)
- When Can an Egress Door Be Locked? Key Locks, Dwelling Doors and Classrooms
- Electrically Locked Egress Doors: Hardware Release and Sensor Release
- Delayed Egress Locks: The 15-Second Rule, the Sign, and the Path Limit
- Door Hardware Height, Opening Force and Closer Timing
- Fire Door Hardware: Latching, Closers, Hold-Opens and Door Prep Limits (CBC 716)
Masonry (C-29)
- Masonry Fireplace: Hearth, Firebox Walls and Clearances
- Sizing the Flue for a Masonry Fireplace
- Chimney Height, Cricket, Spark Arrester and Clearances
- Chimney Seismic Steel, Ties and Strap Anchors
- Grouting Reinforced Masonry: Lifts, Pours and Cleanouts
- Mortar Types and Batching by Volume
- Anchored Masonry Veneer: Ties, Flashing and Weep Holes
- Masonry Wall Safety: Limited Access Zone, Bracing and Stacking
Parking and Highway Improvement (C-32)
Free preview: Parking and Highway Improvement (C-32)
- Accessible Parking Count and Van Spaces
- Accessible Stall Layout, Slope and Markings
- Striping Paint Quantity: Linear Feet to Gallons
- Striping Materials: Temperature, Thickness and Acceptance Checks
- Removing Obsolete Markings: Limits and Pay Quantity
- EV Charging Stalls: Required Counts and Accessible Stalls
- Curb Colors and Fire Lane Clearances
Painting and Decorating (C-33)
Free preview: Painting and Decorating (C-33)
- VOC Content: Reading the CALGreen Coating Limits
- Lead-Safe Painting: When the EPA RRP Rule Applies
- Lead on the Job: Cal/OSHA PEL, Action Level and Trigger Tasks
- Interior Finish Classes: What Can Go on the Wall
- Weather Window: When You May Coat Steel (Caltrans §59-1.03B)
- Film Build: Checking Each Coat and the Total Against the Spec
Pipeline (C-34)
- Sloping a Pipe Trench by Soil Type (Title 8 Appendix B)
- Pipe Trench Width, Bedding, and Backfill Lifts
- Thrust Block Sizing at Bends, Tees, and Dead Ends
- Leakage Testing a Gravity Pipe: Exfiltration and Air Test
- Cathodic Protection of Underground Steel Gas Pipe: Criteria and Test Schedule
- Pressure Testing a Trenched Supply Line (Method A)
Refrigeration (C-38)
Free preview: Refrigeration (C-38)
- Refrigerant Charge Limit for a Room: RCL from CMC Table 1102.3
- Machinery Room Triggers and Emergency Exhaust (CMC 1106)
- Relief Valve Vent Piping: Termination, Back Pressure and Length (CMC 1112)
- Field Pressure Test: Pressure, Test Gas and Declaration (CMC 1116)
- Supermarket Leak-Tight Installation: CALGreen 5.508.2 Pressure Test and Evacuation
- Refrigerated Warehouse Condensers: Design Condensing Temperature and Efficiency (Energy Code 120.6(a))
- Warehouse Evaporators: Specific Efficiency, Fan Control and Static Pressure (Energy Code 120.6(a)3)
- Retail Food Store Refrigeration: Heat Recovery, Subcooling and Condenser Rules (Energy Code 120.6(b))
Roofing (C-39)
- Roof Area, Squares, and Shingle Bundles
- Shingle Slope Limits and Underlayment Layers
- Attic Ventilation: Net Free Area (1/150 and 1/300)
- Low-Slope Roofing: Minimum Slope and Drainage
- Roofing Fall Protection: Title 8 Sections 1730 and 1731
- Shingle Roof Flashing: Drip Edge, Step Flashing, Valleys, and Crickets
Sanitation System (C-42)
Free preview: Sanitation System (C-42)
- Sizing a Septic Tank: Bedrooms, Flow, and Compartments
- Sizing a Leach Field: Soil, Square Feet, and Trench Length
- Sizing a Seepage Pit: Sidewall Area and Block Count
- Setback Distances: Reading Table H 101.8
- Building Sewer Laterals: Fall, Size, Trench, and Cleanouts
- Entering a Septic Tank or Sewer: Confined-Space Atmosphere Rules
Sheet Metal (C-43)
Free preview: Sheet Metal (C-43)
- Sizing Gutters and Leaders: CPC Tables 1103.3 and 1103.1
- Product-Conveying Duct Gauge: CMC Tables 506.2(1) and 506.2(2)
- Type I Kitchen Hoods: Metal, Overhang, and Net Exhaust (CMC 508)
- Grease Duct: Gauge, Slope, Access, and Clearance (CMC 510 and 507.4)
- Clothes Dryer Exhaust Duct: Length, Elbows, and Metal (CMC 504.4)
- Metal Roof Panels: Minimum Slope, Materials, and Fasteners (CBC 1507.4)
- Metal Shear Guarding: the 3/8-Inch Rule and Table G-3 (8 CCR 4227, 4186)
- Press Brake Safeguarding: Safety Distance Ds = 63 x Ts (8 CCR 4214, 4208)
Sign (C-45)
- Wind Inputs and Footing Load for a Sign (CBC 1609, 1605.2)
- Pier Embedment Depth for a Pole or Pylon Sign
- Sign Lighting Power Limits (Energy Code Sec. 140.8)
- Sign Disconnect, Height, and Line Clearance (Title 8 ESO)
- Accessible Signs: Tactile Letters, Braille and Character Height (CBC 11B-703)
- Signs Over the Public Right-of-Way (CBC Chapter 32)
- Plastic Sign Faces and Mall Storefront Signs (CBC 402.6.4, 2606, 2611)
Manufactured Housing (C-47)
Free preview: Manufactured Housing (C-47)
- Soil Bearing Values from the Presumptive Load-Bearing Table
- Sizing Pier Footings from Pier Load and Soil Pressure
- Masonry Pier Height Limits and Wood-to-Ground Clearances
- Lot Drain Inlet, Drain Connector and Water Outlet
- Gas Supply at the Home Site: Demand, Burial, Valves and Air Test
- Crawlspace Ventilation, Vapor Retarder and Site Drainage
Reinforcing Steel (C-50)
Free preview: Reinforcing Steel (C-50)
- Rebar Weight Takeoff: Bar Sizes, Cover, and Tons
- Standard Hooks and Bend Dimensions: What the Code Page Prints
- Lap Splice Length: What Caltrans Section 52 and the CRC Print
- Cover and Clear Spacing: Do the Bars Fit in the Member?
- Minimum Bars in Footings and Plain Concrete Walls: Checking Bar Area
- Rebar Impalement Protection: Covers, Troughs, and the 7-1/2 Foot Test
- Reinforcing Steel Assemblies: Bracing, Hoisting, and Fall Protection
Structural Steel (C-51)
Free preview: Structural Steel (C-51)
- Reading Steel Callouts, Substitutions, and Material Identity
- Steel Weight Takeoff: Pounds per Foot, Plates, Welds, and Tons
- High-Strength Bolts: Assemblies, Holes, and Caltrans Verification Testing
- Sling Angles and the Multiple-Lift Rules
- Column Anchorage, Two-Bolt Release, and Double Connections
- Fall Protection on Skeleton Steel: Connector Heights, Perimeter Cable, and the CDZ
Swimming Pool (C-53)
Free preview: Swimming Pool (C-53)
- Turnover Time, Flow Rate, and Pump Head
- Sizing a Filter: Flow Rate per Square Foot
- Suction Outlets and Entrapment: Two Drains and the Velocity Limits
- Pool Floor Slope, the 4-1/2 Foot Line, and Depth Markers
- Pool Deck Slope, Coping, and the 9-Inch Handhold
- Pool Heaters and Solar: Energy Code Checklist and Collector Sizing
- Pool Electrical Clearances: Receptacles, Lights, and Cords
- New Residential Pools: Choosing Two of the Seven Safety Features
Tile (C-54)
- Tile Layout: Centering and Balanced Cuts (Practice)
- Floor Framing Under Tile: L/360 and the Joist Span Table
- Shower Receptor: Slope, Curb, Lining Height and Flood Test
- Backer Board and Wet-Wall Tile Heights
- Accessible Shower Floors: Threshold, Slope and Grate
- CALGreen VOC Limits: Tile Adhesives and Sealants
- Cutting Tile Safely: Silica Limits, Wet Cutting, and the 8-Hour TWA
Well Drilling (C-57)
Free preview: Well Drilling (C-57)
- Annular Seal: Depth, Hole Size, and Seal Volume
- Siting a Well: Separation Distances and the Encroachment Seal
- Annular Seal Mixes: Ratios, Additives, and Set Times
- Wellhead Pad and Surface Seal: Sizing the Base and Sealing Openings
- Disinfecting a Well: Chlorine Dose from Table 6
- Destroying an Abandoned Well: Fill Plan and Volume Check
Welding (C-60)
- Choosing the Filter Lens Shade (Table EP-1)
- Welding Fume: Calculating the 8-Hour TWA and the Additive Limit
- Welding Ventilation, Toxic Metals, and Coated Surfaces
- Oxy-Fuel Setup: Cylinder Separation, Hose, and Pressure Limits
- Hot Work: Permit, Fire Watch Timing, and the Extinguisher Rule
- Arc Welding Circuit: Return Cable Capacity, Splices, and Shutdown
Limited Specialty (D-Series) (C-61)
Free preview: Limited Specialty (D-Series) (C-61)
- D-03 Awnings: Clearance, Projection and Fabric Rules
- D-28 Powered Doors and Automatic Gates: Leaf Count, Controls and Backup Power
- D-34 Toilet Partitions: Accessible Compartment Size, Door and Grab Bar Layout
- D-35 Pool Pumps: Filtration Flow Limit, System Head and Piping Rules
- D-39 Scaffolding: Duty Class, 4-to-1 Design Load and Plank Spans
- D-49 Tree Service: Felling Notch, Climbing Line and Power-Line Limits
Hazardous Substance Removal (HAZ)
Free preview: Hazardous Substance Removal (HAZ)
- HAZWOPER Training Hours: Who Needs 40, 24 and 8
- Choosing a PPE Level: A, B, C or D on a Hazardous Site
- PELs, 8-Hour TWA and the Mixture Rule
- UST Removal: Counting the Closure Soil Samples
- Out-of-Service Tanks: The 90-Day, One-Year and 365-Day Clocks
- UST Releases: The 8-Hour, 24-Hour, 5-Day and 45-Day Clock
Law & Business
- Choosing a Business Entity: Liability, Taxes, and What Happens to the License
- The Qualifying Individual: RMO, RME, and the 90-Day Replacement Clock
- Bonds, Liability Insurance, and Workers’ Comp: What the License Requires on File
- The Home Improvement Contract Checklist: Down Payment, Change Orders, and Right to Cancel
- The Preliminary Notice and Mechanics Lien Calendar
- Your First Employee: the ABC Test, Payroll Taxes, and Deposit Deadlines
- Reading a Balance Sheet: Working Capital, Current Ratio, and Quick Ratio
- Public Works Basics: DIR Registration, Bonds, Prevailing Wage, and Certified Payroll
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