CSLB General Building (B) flashcards

A blocked shear wall has solid lumber backing at all panel edges (including horizontal joints), enabling full edge nailing and higher rated shear capacity than an unblocked assembly.

• Blocking supports horizontal panel joints
• Blocked walls have higher allowable shear values
• Unblocked panels rely only on vertical framing for edge nailing

Memory trick: 'Block it to lock it — full edges, full strength.'

Standard nailing for roof sheathing panels is 6 inches on center at supported edges and 12 inches on center in the field.

• 6 in o.c. at edges, 12 in o.c. field is typical minimum
• Tighter spacing (e.g., 6/6) may be required in high wind/seismic zones
• Uses 8d common nails typically for 15/32-in to 19/32-in sheathing

Memory trick: Six on the edge, twelve in the middle.

Guidelines requiring fresh concrete to be maintained at a minimum temperature of 50°F for at least 3 days after placement in cold weather to prevent freeze damage and ensure proper hydration.

• Minimum protected temperature is 50°F
• Minimum protection period is 3 days for normal structures
• Longer protection needed for thin sections or high early strength requirements

Memory trick: 'Fifty for three' keeps fresh concrete from freezing before it gains strength.

Winder stairs must maintain a minimum tread depth of 6 inches at the narrow end and 10 inches at a point 12 inches from the narrow end to ensure safe footing.

• 6-inch minimum at narrowest point
• 10-inch minimum at 12 inches from narrow end
• Applies to curved/turning stair sections

Memory trick: Six at the point, ten a foot in — winders still need room for your feet.

Vapor retarders are grouped into three classes based on water vapor permeance, which determines how much moisture diffusion they allow through a wall assembly.

• Class I: ≤0.1 perms (foil, polyethylene)
• Class II: >0.1 to 1.0 perms (kraft-faced batts)
• Class III: >1.0 to 10 perms (latex paint, some primers)

Memory trick: 'I is impermeable, III lets it through' — lower Roman numeral, lower perm rating.

Fire blocking seals small concealed cavities; draft stopping subdivides larger concealed spaces like attics to limit fire and smoke spread.

• Fire blocking: stud walls, floor/ceiling junctions, stair stringers
• Draft stopping: large attics and floor/ceiling assemblies over specified area thresholds
• Both limit unseen fire travel but at different scales

Memory trick: Small gaps get blocked, big attics get stopped.

Fire-rated gypsum ceiling assemblies require tighter fastener spacing than standard walls to maintain structural integrity during a fire.

• 12 inches o.c. typical field spacing on rated ceilings
• Framing spacing affects required fastener spacing
• Edge/perimeter spacing often tighter than field

Memory trick: 'Ceilings need closer screws to hold the fire fuse.'

The minimum time concrete must cure before forms can be safely removed, varying by whether the form is load-bearing.

• Non-load-bearing side forms: typically 12-24 hours
• Load-bearing/structural forms (beams, slabs): several days to weeks
• 28-day cure is the standard for reaching design compressive strength

Memory trick: Side forms come off in a day; structural forms wait and stay.

An excavation protection method that cuts trench walls into a series of horizontal steps or benches, permitted only in soils with sufficient cohesion (Type A or B).

• Allowed in Type A and B soil only
• Not permitted in Type C soil
• Alternative to sloping or shoring for trench protection

Memory trick: 'Benching needs backbone' — only cohesive soils (A & B) can hold a stepped shape.

Excavated soil and other materials must be kept at least 2 feet from the edge of a trench to prevent them from falling back into the excavation.

• 2-foot minimum setback required by OSHA/Cal-OSHA
• Applies to spoil, equipment, and materials
• Reduces risk of cave-in from surcharge loading

Memory trick: Two feet back keeps the dirt off your back.

The California Residential Code requires a minimum vertical headroom clearance of 80 inches (6'8") for stairways, measured from the nosing line to any overhead obstruction.

• Standard minimum: 80 inches
• Spiral stair exception: 78 inches
• Measured from a line through the tread nosings

Memory trick: Six-eight is the height, or your head takes a hit.

The sand cone test measures in-place soil density in the field, which is then divided by the laboratory maximum Proctor dry density to calculate percent relative compaction.

• Relative compaction = field dry density ÷ max Proctor density
• Common specification minimum is 90% relative compaction
• Sand cone test is a common field density testing method

Memory trick: Divide field density by lab max — the percentage tells the compaction story.

Rafter ties resist outward thrust from sloped rafters and are most effective when placed in the lower third of the attic near the top plate.

• Acts as tension member resisting rafter spread
• Best placed low, near wall top plate
• Ceiling joists often serve this function when aligned with rafters

Memory trick: Low ties tie down the thrust.

A rebar grade number indicates the minimum yield strength of the steel in ksi (thousands of psi); Grade 60 rebar has a minimum yield strength of 60,000 psi.

• Grade 60 = 60,000 psi minimum yield strength
• Most common rebar grade in general construction
• Bar size (#3-#18) is separate from grade designation

Memory trick: 'Grade equals strength in thousands' — Grade 60 means 60,000 psi yield.

NEC 300.4(A)(1) requires steel protective plates when wiring passes through framing holes closer than 1-1/4 inches to the framing edge, to prevent nail/screw punctures.

• Minimum 1-1/4 inch clearance avoids need for a plate.
• Steel plates must be at least 1/16 inch thick.
• Applies to both bored holes and notches in framing.

Memory trick: 'Too close to the edge? Steel plate saves the wedge (cable).'

A balanced attic ventilation system splits the total required net free vent area evenly between intake (soffit) and exhaust (ridge) vents to promote consistent low-to-high airflow.

• Standard balance is 50% intake, 50% exhaust
• Intake vents are placed at the eaves/soffits
• Exhaust vents are placed at the ridge or upper roof

Memory trick: 'Half in, half out' — balanced attics split air flow evenly.

Wood structural panel subfloors are typically fastened with 8d common nails spaced 6 inches on center at panel edges and 12 inches on center at intermediate supports.

• 6 in o.c. at edges, 12 in o.c. in field is standard
• 8d common nails are typical for standard subfloor thickness
• Tighter spacing may be required for diaphragm shear demands

Memory trick: 'Six at the edge, twelve in the middle keeps the floor from a diddle.'

To find the number of risers, divide total rise by the maximum allowed riser height and round up to the next whole number, then divide total rise by that number of risers to get the actual uniform riser height.

• Formula: risers = ceiling(total rise ÷ max riser height)
• Actual riser height = total rise ÷ number of risers
• All risers in a flight must be within 3/8 inch of each other

Memory trick: 'Round up the risers, then split the rise fair.'

Drip edge metal is installed under the underlayment at eaves and over the underlayment at rake edges to properly shed water.

• Eave: drip edge under underlayment
• Rake: drip edge over underlayment
• Prevents water from getting behind fascia and rake trim

Memory trick: Under at the eave, over at the rake — remember 'UE-OR'.

Allowable bending stress (Fb) and modulus of elasticity (E) vary by wood species even within the same grade designation, directly affecting a member's span capacity.

• Same grade name ≠ same allowable stress across species
• Douglas fir-larch generally has higher Fb than Hem-fir
• Substituting a weaker species requires larger size or reduced span

Memory trick: Same grade, different tree, different strength decree.

Cal/OSHA mandates a protective system for trenches 5 feet or deeper unless the excavation is entirely in stable rock.

• 5-foot trigger depth for protective systems
• Options include shoring, shielding (trench boxes), or sloping/benching
• Type C soil is the least stable, requiring more conservative slopes

Memory trick: 5 feet down, protection's the crown.

Continuous lateral bracing installed on truss bottom chords per the truss designer's drawings to prevent lateral buckling when the chord experiences compression, such as from wind uplift.

• Specified at intervals per truss design drawings (e.g., 10 ft o.c.)
• Prevents buckling of bottom chord under uplift/compression
• Roof sheathing only braces the top chord, not the bottom

Memory trick: 'Top chord's braced by sheathing; bottom chord needs its own bracing.'

A steel connector installed at the ends of a shear wall to resist uplift (tension) forces created by lateral load overturning moments.

• Resists overturning, not shear itself
• Typically bolted to end studs and anchored to foundation
• Critical at narrow or high-aspect-ratio shear walls

Memory trick: Lateral force tries to tip the wall—hold-downs hold it down.

ACI 318 rule stating concrete is acceptable if the average of three consecutive strength tests meets or exceeds f'c and no single test is more than 500 psi below f'c.

• Based on 28-day cylinder breaks
• Average of 3 tests must equal or exceed f'c
• No single test may fall more than 500 psi below f'c

Memory trick: 'Average wins, but no big loser allowed' — check both the mean and the worst test.

Fire blocking material seals concealed spaces in framing to slow the spread of fire and combustion gases.

• Required in concealed wall and floor cavities
• Common materials include 2x lumber, gypsum board, and mineral wool
• Different from draft stopping, which limits air movement in larger concealed spaces

Memory trick: Block the path, stop the flash.

A polyethylene sheet placed under a concrete slab to block moisture from the soil from entering the slab.

• Typically 6-10 mil polyethylene sheeting
• Placed directly beneath the slab, often over a gravel base
• Prevents moisture damage to flooring and finishes above

Memory trick: Vapor barrier = umbrella for the slab, blocking ground moisture.

Construction proceeds from structural framing to MEP rough-in, then insulation, then drywall closure, with inspections required at each stage before proceeding.

• Framing inspected before rough-in trades begin.
• Insulation inspected after rough-in but before drywall.
• Skipping sequence risks failed inspections and rework.

Memory trick: 'Frame it, wire/pipe/duct it, insulate it, then close it up.'

A system (Type A, B, C) used to classify soil stability for excavation safety, based on cohesion, unconfined compressive strength, and site conditions.

• Type A: cohesive soil, UCS ≥ 1.5 tsf, most stable
• Type B: cohesive soil, UCS 0.5-1.5 tsf, or unstable fissured soil
• Type C: granular soil or UCS < 0.5 tsf, least stable, requires most protection

Memory trick: A is for 'awesome strength,' C is for 'crumbly and weak.'

The pressure fresh concrete exerts on formwork increases with faster placement rates, higher slump, and lower temperatures, requiring adequately designed bracing and ties.

• Faster pour rate = greater unset concrete height = higher pressure
• High slump and cold temperatures also increase lateral pressure
• Formwork must be designed for peak lateral pressure, not just concrete weight

Memory trick: Pour faster, push harder — the forms feel more fluid force.

Skylight curbs must extend a minimum of 4 inches above the roofing plane to keep water and debris away from the unit's seals and glazing.

• Minimum curb height is 4 inches above roofing surface
• Applies to curb-mounted skylight installations
• Flashing must integrate with roofing underlayment and shingles around the curb

Memory trick: 'Four inches keeps water off the glass' — same 4-inch rule as other roof penetrations.

Temporary wood frames set outside excavation limits with string lines used to mark and re-establish building corners and reference lines during construction.

• Placed outside the excavation area so they aren't disturbed
• String lines mark exact building corners
• Allow layout to be re-checked throughout construction

Memory trick: Batter boards hold the strings that never let the corners go missing.

Code requires fire blocking in concealed spaces between stair stringers and walls at the top and bottom of each stair run.

• Prevents fire from traveling through hidden stair cavities
• Required at both top and bottom of the stair run
• Distinct from fire blocking required in vertical stud cavities

Memory trick: Seal the stairs top and bottom, or fire climbs unstoppin'.

Grade stamps include a moisture content designation such as S-DRY (surfaced dry, ≤19% MC) or S-GRN (surfaced green, >19% MC) at the time of surfacing.

• S-DRY = 19% or less moisture content at surfacing
• S-GRN = surfaced green, moisture content over 19%
• Grade stamp also shows species, grade, and mill/grading agency

Memory trick: 'S-DRY stays under nineteen, keeping shrinkage lean.'

Interior partitions running parallel to floor joists must be supported by a doubled joist or blocking when they don't align directly over a joist.

• Prevents floor sag under partition weight
• Doubled joist or blocking placed beneath partition
• Applies to both bearing and non-bearing partitions with sufficient load

Memory trick: Wall between joists? Double up below!

A ridge board is a non-load-bearing member requiring rafter ties, while a ridge beam is a structural member that supports rafter reactions directly.

• Ridge board = nailing point only, needs ties
• Ridge beam = structural, carries rafter loads
• Ridge beams often need post/wall support

Memory trick: Board = 'boring' (no load); Beam = 'bears' the load.

Concealed spaces behind combustible cornices and soffits require fire blocking at maximum 20-foot intervals to limit horizontal fire spread.

• Separate requirement from the 10-foot vertical stud cavity rule
• Applies to continuous horizontal concealed spaces at eaves
• Prevents fire from running unchecked along roof edges

Memory trick: Twenty feet along the eave, keeps the fire well-behaved.

California energy code requirement mandating minimum solar reflectance and thermal emittance for roofing to reduce building cooling loads.

• Low-slope aged reflectance minimum: 0.63
• Steep-slope aged reflectance minimum: 0.20
• Reduces urban heat island effect and cooling costs

Memory trick: 'Sixty-three keeps low-slope roofs cool and free.'

A weakened plane in concrete that forms when a new batch is placed against concrete that has already begun to set, preventing proper bonding between layers.

• Caused by delays in placement exceeding initial set time
• Prevention includes continuous pours, retarders, or proper joint preparation
• Weakens structural integrity and can allow water infiltration

Memory trick: A cold joint is concrete that showed up too late to the party.

The minimum footing width needed is calculated by dividing the applied load per linear foot by the soil's allowable bearing capacity.

• Formula: Width = Load (lb/ft) ÷ Bearing Capacity (psf)
• Soil bearing capacity is determined by geotechnical report or code tables
• Undersized footings can cause settlement or foundation failure

Memory trick: Divide the load by what soil can hold to get width in feet, bold.

Fireblocking must be installed in concealed wall cavities at vertical intervals not exceeding 10 feet to limit fire spread.

• Max 10-ft vertical spacing in stud walls
• Also required at floor/ceiling levels and stair stringers
• Materials: 2x lumber, gypsum, or approved noncombustible material

Memory trick: Ten feet, block the heat.

A standardized soil test result (ASTM D4829) used to classify soil expansion potential, ranging from very low to very high based on defined EI value ranges.

• 0-20 = very low, 21-50 = low, 51-90 = medium
• 91-130 = high, above 130 = very high
• Higher EI requires more foundation mitigation measures

Memory trick: '75 sits in the middle' — medium expansion soils fall between 51 and 90.

The minimum vertical distance a footing must be embedded below undisturbed ground surface per building code, ensuring adequate bearing and protection from surface effects.

• Code minimum is 12 inches below undisturbed grade for standard footings
• Deeper depths required for frost lines or expansive soil per soils report
• Footings must bear on undisturbed or properly compacted engineered fill

Memory trick: Twelve inches down keeps your footing sound.

Joints cut or formed into a concrete slab at regular intervals to control the location of shrinkage cracks.

• Rule of thumb: spacing (ft) = 2 to 3 times slab thickness (in)
• Joints should be cut within 6-12 hours of finishing for best crack control
• Panel aspect ratio should not exceed about 1.5:1

Memory trick: Thickness times two or three tells you where the joint should be.

Total thermal resistance of a wall assembly is calculated by adding the R-values of each material layer in series, including insulation, sheathing, and air films.

• R-values in series are additive
• Continuous insulation adds to cavity insulation value
• Air films contribute small but real R-value

Memory trick: 'Stack the R's like bricks to build the wall's true value.'

Concrete quantity is calculated by finding volume in cubic feet (L x W x H) and converting to cubic yards by dividing by 27.

• 1 cubic yard = 27 cubic feet
• Formula: Volume (cf) = Length x Width x Depth
• Always round up when ordering to avoid running short during a pour

Memory trick: 27 cubic feet make a yard — divide and round to avoid falling hard.

For a simply supported beam carrying a uniform load, each end reaction equals half the total load (total load = w × L, reaction = total load ÷ 2).

• Total load = uniform load (plf) × span length (ft)
• Each end reaction = total load ÷ 2 for a simple span
• Jack studs must be sized/counted to bear the calculated end reaction

Memory trick: 'Multiply load by length, then split the strength.'

A metal flashing installed at the base of stucco walls to allow moisture drainage; code sets minimum clearances above grade and paving to prevent water intrusion.

• 4 inches minimum above earth/grade
• 2 inches minimum above paved surfaces
• Prevents wicking and rot at wall base

Memory trick: 'Four inches from dirt keeps stucco alert.'

The minimum overlap required when two top plate members are joined to maintain continuity of the wall's tension and load path.

• Minimum 24-inch lap required
• Alternative: steel splice plate with equivalent strength
• Splices should be staggered from joints below

Memory trick: '24 for the floor' — plates need two feet of overlap.

King studs run full wall height beside an opening; jack (trimmer) studs are cut shorter to support the header and transfer its load to the sole plate.

• Jack studs carry header end reactions to the foundation
• King studs provide full-height framing and tie into top/bottom plates
• Both are required at wider openings for proper load transfer

Memory trick: 'Jacks jack up the header's load.'

The end reaction of a header increases with span and load, requiring adequate jack stud bearing area to transfer that load down to the foundation.

• Reaction load = half the total header load for a simple span
• Jack studs (trimmers) carry header reactions to the sill/foundation
• Wider spans and heavier loads require more jack studs or larger studs

Memory trick: 'Bigger span, bigger load, more studs to carry the road.'

Traditional cement plaster system applied in three layers over lath: scratch, brown, and finish coats, each serving a distinct structural or aesthetic purpose.

• Scratch coat is scored horizontally to key the brown coat
• Brown coat provides a flat, true plane for finish application
• Finish coat provides color and texture and is the thinnest layer

Memory trick: 'Scratch, Brown, Finish' — like sanding rough to smooth to polished.

Fire blocking must be installed at a maximum vertical spacing of 10 feet within concealed stud wall cavities.

• Applies to concealed spaces of stud walls and partitions
• Also required at floor and ceiling levels
• Prevents chimney-effect fire spread in tall walls

Memory trick: Ten feet tall, block the wall.

Vapor retarder placement depends on climate: cold climates need interior-side vapor control to stop winter vapor drive, while other climates may not require or even discourage it.

• Vapor drives toward the cold side of an assembly
• Cold Climate Zone 16 typically requires interior vapor retarders
• Interior vapor retarders in warm/mixed climates can trap moisture and cause damage

Memory trick: Vapor chases the cold — block it before it gets there.

ASTM C840 requires control joints in large gypsum board ceiling or wall runs so no single field exceeds 30 feet in either direction, accommodating structural movement and preventing cracking.

• Maximum unbroken run is 30 feet per ASTM C840
• Divide total length by segments to verify each is ≤30 ft
• Perimeter relief or doorway breaks can also satisfy the requirement

Memory trick: 'Divide till under thirty' — keep dividing the run until each piece fits under 30 feet.

Concrete cast directly against and permanently exposed to earth requires greater minimum rebar cover than formed concrete.

• 3 inches minimum cover for concrete cast against earth
• 1.5 inches typical for formed concrete exposed to weather
• 3/4 inch typical for interior, unexposed concrete

Memory trick: Dirt-formed footings need the thickest skin — 3 inches to protect within.

NEC 110.26 requires a dedicated clear working space in front of electrical panels, generally 30 inches wide and 36 inches deep, that must remain free of unrelated piping, ducts, or equipment.

• Working space must extend to a specified height above the panel.
• Foreign systems (plumbing, HVAC) generally cannot occupy this dedicated space.
• Piping must never penetrate the panel enclosure itself.

Memory trick: 'Give the panel its 30x36 personal space—no pipes allowed in its face.'

Load-bearing walls require lumber graded Stud or better with certified structural allowable stresses, unlike Utility or Economy grades used for non-structural framing.

• Stud grade rated for load-bearing walls
• Utility/Economy grades = non-structural only
• Grade stamp confirms allowable stress values

Memory trick: Bearing walls bear weight—use Stud grade, not 'Utility junk.'

Prescriptive shear wall nailing schedules specify nails because of their tested ductile performance under cyclic lateral loads; substituting screws requires engineering approval.

• Nails bend and yield; some screws shear off suddenly
• Substitutions must be approved by engineer or code official
• Shear wall schedules are based on tested assemblies

Memory trick: Don't swap without a stamp—screws need engineering approval first.

A sloped, waterproof flashing membrane installed at the base of a window rough opening to drain incidental water to the building exterior.

• Sloped toward the exterior for positive drainage
• Works with head and jamb flashing as part of a complete window flashing system
• Protects wall framing and sheathing from hidden water damage

Memory trick: Pan catches the drips before they sink the ship.

A fire-resistant drywall product with reinforcing glass fibers, commonly used in 5/8-inch thickness to achieve one-hour fire-rated assemblies.

• 5/8-inch Type X = standard 1-hour rating component
• Used in garages, corridors, and shared walls
• Different from standard 1/2-inch drywall

Memory trick: 'X marks the eXtra fire protection.'