CSLB General Building (B) — All Questions

For wood structural panel sheathing, how far should nails typically penetrate into the framing member to be effective?

• a.The full length of the stud, so the nail is buried end to end in wood
• b.At least about 1 inch into the framing✓
• c.Exactly the panel thickness
• d.Just past the panel face

Fastening schedules expect roughly 1 inch or more of penetration into the supporting framing so the nail develops withdrawal and shear resistance. Barely reaching the framing or matching only the panel thickness leaves too little embedment; penetrating the full stud is neither possible nor required.2025 CA Residential Code §R602.3

A glued-and-nailed subfloor squeaks after installation. Which construction detail MOST directly reduces the squeaks?

• a.Increasing panel-edge gaps to 1/2 inch so the panels can move freely against each other
• b.Applying continuous construction adhesive on joists before setting panels and fastening while the adhesive is wet✓
• c.Leaving tongue-and-groove joints loose so the panel edges are free to flex slightly underfoot
• d.Using shorter nails than specified so they draw the panel down with less grip in the joist

A glued-and-nailed floor bonds the panel to the joist so the two act together and do not rub, the main cure for squeaks; adhesive must be continuous and fastened before it skins over. Oversized gaps, shorter nails, and loose T&G joints all increase movement and noise.

Which panel-joint practice BEST avoids a continuous weak line across a subfloor or roof deck?

• a.Gluing every joint solid so panels cannot move and the whole deck acts as one continuous sheet
• b.Using only full sheets with no cut pieces so every panel keeps its factory edges on all four sides
• c.Aligning all end joints on the same joist so each seam is backed by solid framing beneath it
• d.Staggering panel end joints so they fall on different supports in adjacent rows✓

Staggering end joints (a brick-like pattern) keeps adjacent rows from sharing one continuous seam, distributing load and stiffness. Aligning all joints creates a hinge line; gluing does not address the seam pattern; and using only full sheets is neither practical nor the governing principle.2025 CA Residential Code §R503.1

Beyond structure, why is careful sealing of subfloor and sheathing joints emphasized in current California construction?

• a.It limits air leakage, supporting the Energy Code's building-envelope tightness goals✓
• b.It allows nails to be spaced farther apart because the sealant itself holds the panel edges down on the framing
• c.It replaces the need for wall insulation because sealed joints alone keep heat from crossing the wall
• d.It increases the panel span rating

Sealed sheathing joints reduce uncontrolled air leakage through the envelope, supporting the Energy Code's air-tightness objectives and comfort/efficiency. Sealing does not change span ratings, replace insulation, or permit wider nail spacing, which is set by the structural fastening schedule.2025 CA Energy Code

Where wood structural panels serve as combination subfloor-underlayment to receive resilient flooring directly, which panel characteristic is MOST important?

• a.The heaviest available panel
• b.A touch-sanded face and a rating for combination subfloor-underlayment✓
• c.Maximum knot size
• d.Darkest face veneer, so the deepest panel color is hidden once the resilient flooring is laid

Panels used as subfloor-underlayment for thin resilient flooring must be specifically rated for that use and have a smooth (touch-sanded) face so joints and grain do not telegraph. Knot size, veneer color, and sheer weight are not the controlling factors for a finish-ready underlayment surface.2025 CA Residential Code §R503.2.4

In a framed wall opening, what is the PRIMARY structural role of the header?

• a.To seal the opening against air leakage around the window
• b.To provide a nailing surface for drywall only above the opening
• c.To carry loads from above across the opening to the studs on each side✓
• d.To hold the window frame square while the trim is installed

A header is a beam that spans the opening and transfers the roof, ceiling, or floor loads above it down to the jack (trimmer) studs on each side and into the foundation. Drywall nailing, air sealing, and squaring the window are secondary or unrelated functions.2025 CA Residential Code §R602.7

In header framing, what is the difference between a king stud and a jack (trimmer) stud?

• a.The king stud supports the header; the jack stud runs full height from the bottom plate to the top plate beside it
• b.Both run full height and neither supports the header, which rests instead on the plates above the opening in the wall
• c.The jack stud is always doubled and the king stud is never used in framing an opening of any width or any load above it
• d.The king stud runs full height beside the opening; the jack stud is cut to support the header end✓

The king stud extends full height from plate to plate alongside the opening and is nailed to the header for lateral stability, while the jack (trimmer) stud is shorter, nailed to the king stud, and directly supports the underside of the header end. Saying the king stud supports the header while the jack runs full height simply reverses the two roles. Saying both run full height and neither supports the header leaves the header end with nothing to bear on. And saying the jack is always doubled while the king is never used removes the full-height member that ties the opening back to the plates.2025 CA Residential Code §R602.7

As a header spans a wider opening and carries more load, how does the required number of jack (trimmer) studs at each end typically change?

• a.It decreases because the header gets stiffer and spreads its own load back along the wall
• b.Jack studs are removed and replaced by the king stud only, which carries the header end by itself
• c.It stays at one regardless of span
• d.It increases so the added bearing area can carry the greater end reaction✓

Wider spans and heavier loads raise the reaction delivered to each header end, so codes and manufacturer tables call for additional jack studs to provide enough bearing area beneath the header. The number does not decrease with span, is not fixed at one, and a king stud cannot substitute for bearing jacks.2025 CA Residential Code §R602.7

What is a cripple stud in wall framing?

• a.A stud that has been notched more than 40 percent
• b.The full-height stud at a corner
• c.A stud rotated 90 degrees for a partition intersection so the crossing wall has a nailing surface
• d.A short stud above a header or below a sill that continues the stud pattern✓

A cripple stud is a shortened stud that fills the space above a header (or below a window sill), continuing the regular stud spacing so sheathing and top/bottom framing stay supported. It is defined by length and location, not by notching, corner position, or rotation.2025 CA Residential Code §R602.7.4

A framer builds exterior corners using a three-stud arrangement that leaves room for insulation and provides drywall backing. What is the MAIN advantage of this over a solid stud-packed corner?

• a.It uses more lumber than a solid packed corner and puts more wood at the intersection
• b.It allows insulation into the corner cavity, reducing thermal bridging, while still backing the interior finish✓
• c.It makes the corner load-bearing where a solid corner is not, carrying framing loads above
• d.It eliminates the need for corner sheathing because the studs alone brace that corner

An insulated (California/three-stud) corner leaves a cavity that can be insulated, cutting the thermal bridge a solid lumber-packed corner creates, and still provides a nailing surface for interior drywall. It uses less lumber, does not remove sheathing, and both corner types can be load-bearing.2025 CA Energy Code

In an EXTERIOR bearing wall, what is the MAXIMUM depth a stud may be NOTCHED, expressed as a fraction of its depth?

• a.10 percent
• b.40 percent
• c.25 percent✓
• d.60 percent

In an exterior or bearing wall, a stud may be notched to a maximum of 25 percent of its depth. Forty percent is the notch limit for non-bearing partitions, 60 percent is a bored-hole limit for non-bearing studs, and 10 percent is more restrictive than the code requires.2025 CA Residential Code §R602.6

For a bored hole in an EXTERIOR bearing-wall stud that will not be doubled, what is the MAXIMUM hole diameter as a fraction of the stud depth, and how close may it come to the stud edge?

• a.25 percent, 1/4 inch from the edge, leaving only a thin lip of wood on the outside face of the stud
• b.40 percent, with at least 5/8 inch of wood between the hole edge and the stud edge✓
• c.60 percent, no edge limit, because the wood left on each side of the hole is not counted in the rule
• d.50 percent, flush with the edge, so the pipe or wire can drop straight into the open slot from the side

R602.6 allows a bored hole up to 40 percent of the stud depth in an exterior or bearing wall without doubling the stud, and the hole must stay at least 5/8 inch from the stud edge. 60 percent is the overall limit, allowed in these walls only with a doubled stud, and the edge distance still applies. 25 percent is the notch limit, and holes may never be flush with the edge.2025 CA Residential Code §R602.6

When a pipe notch or bore in a wood stud leaves less than 1-1/4 inch of wood between the pipe and the exposed face, what protection does the code require?

• a.Filling the notch with expanding foam so the cavity is solid and the pipe cannot rattle against the wood around it
• b.Nothing, provided the pipe is copper, since the metal wall of the tubing is hard enough to turn a driven fastener
• c.Doubling the drywall thickness
• d.A steel plate or shield of adequate thickness over the area to guard against fastener penetration✓

Where less than 1-1/4 inch of wood remains between a pipe and the stud face, a steel nail plate (typically at least 16 gauge) must protect the pipe so later nails or screws cannot puncture it. Pipe material, extra drywall, and foam do not stop a driven fastener from reaching the pipe.

Where the two members of a double top plate are spliced (end joints), how must the joints in the upper and lower plates be arranged?

• a.Directly over each other for a tight fit, so both plates break at the same point
• b.Within 6 inches of each other
• c.Offset by at least 24 inches so the joints do not line up✓
• d.Both centered over the same stud

Double top-plate splices must be offset at least 24 inches so the two joints never coincide, keeping the plate continuous for load transfer and tension across the wall. Stacking the joints, centering both on one stud, or spacing them only 6 inches apart would create a weak, hinged line.2025 CA Residential Code §R602.3.2

Fireblocking is required in concealed wall spaces primarily to accomplish what?

• a.Cut off concealed draft openings and slow the spread of fire and hot gases through hidden spaces✓
• b.Add structural shear strength to the wall so the framing resists racking loads
• c.Support plumbing pipes running vertically through the concealed wall cavity
• d.Provide a nailing surface for siding fastened to the outside of the wall framing

Fireblocking closes concealed vertical and horizontal openings (such as at floor and ceiling levels and around soffits) so fire and hot gases cannot travel unchecked through the framing cavities. It is not intended for shear strength, siding attachment, or supporting pipes.2025 CA Residential Code §R602.8

Which material is generally ACCEPTABLE as fireblocking in a concealed stud space?

• a.Uncased fiberglass batts hung loosely in the cavity
• b.Loose sawdust
• c.A sheet of ordinary polyethylene film
• d.Nominal 2-inch lumber fitted to the opening✓

Approved fireblocking includes 2-inch nominal lumber cut to fit, two thicknesses of 1-inch lumber, wood structural panels, gypsum board, and certain mineral or approved materials. Loose sawdust and thin polyethylene are combustible or ineffective, and unsupported batts alone are not accepted general fireblocking except where specifically permitted.2025 CA Residential Code §R602.8

In a braced wall line, what does the term 'braced wall panel' refer to?

• a.Any interior partition that divides two rooms, whether or not it is sheathed and fastened in any particular way by the framer
• b.The drywall finish applied to the room side of a wall, which closes in the framing and gives the room its finished surface
• c.A specific length of wall, sheathed and fastened as prescribed, that resists lateral (wind/seismic) loads✓
• d.A prefabricated window header assembly that spans the opening and carries the load from the wall framing and roof above it

A braced wall panel is a defined, code-compliant segment of a braced wall line, built and fastened by an approved bracing method, that provides the wall's resistance to wind and earthquake forces. It is not simply any partition, the drywall finish, or a header assembly.2025 CA Residential Code §R602.10

In conventional roof framing, where should rafter ties (which resist the outward thrust of rafters) generally be located?

• a.Halfway up the rafter length, where the tie is easy to reach and clears the attic floor
• b.In the lower third of the attic (rafter) height, near the top-plate level✓
• c.Anywhere, as long as they are nailed to the rafters with the fasteners the plan calls for
• d.At the ridge

Rafter ties resist the outward spreading thrust rafters exert on the walls and are most effective near the bottom of the rafters, in the lower third of the attic height. Placing them at the ridge (collar-tie zone) or midheight greatly reduces their ability to hold the walls in; location is not arbitrary.2025 CA Residential Code §R802.5

What is the practical difference between a collar tie and a rafter tie in a gable roof?

• a.A collar tie carries the floor load down from the ceiling framing below, while a rafter tie carries the ridge and holds the peak of the roof up in place
• b.Both must be steel
• c.A collar tie is placed in the upper third to resist ridge separation/uplift, while a rafter tie near the plate resists outward wall thrust✓
• d.They are identical terms

A collar tie sits in the upper third of the roof and mainly keeps the rafters from separating at the ridge under wind uplift, while a rafter tie sits low, near the wall plates, and resists the outward horizontal thrust that would push the walls apart. They are not identical, do not carry floor load, and need not be steel.2025 CA Residential Code §R802.4

When rafters frame to a non-structural ridge board (not a ridge beam), what is the minimum requirement for that ridge board's depth?

• a.Exactly 2 inches regardless of rafter size or cut
• b.Twice the rafter depth measured at the plumb cut
• c.Half the rafter depth measured at the plumb cut
• d.Not less than the cut end (plumb-cut depth) of the rafter✓

A ridge board must be at least as deep as the cut (plumb) end of the rafters bearing against it so the full rafter end seats against the board. A fixed 2 inches, twice, or half the rafter depth would either under- or over-size the board relative to the rafter end it must fully support.2025 CA Residential Code §R802.3

Why does a structural RIDGE BEAM allow a roof to be built without rafter ties, whereas a simple ridge BOARD does not?

• a.A ridge beam carries the rafter loads to posts/bearing points, so rafters do not push the walls outward✓
• b.The ridge board is stronger than a beam and can hold the upper ends of the rafters with no posts or bearing walls under it
• c.The ridge beam is lighter than a board, so the rafters carry less weight at the peak and spread less at the walls below
• d.Ridge boards are only used on flat roofs, where there are no sloping rafters at all that could push the walls outward

A structural ridge beam supports the upper ends of the rafters and carries that load down to posts or bearing walls, so the rafters act as supported members and generate no outward thrust, eliminating the need for rafter ties. A ridge board only aligns rafters and offers no vertical support, so ties are required to resist thrust; calling the board the stronger of the two ignores that nothing beneath it carries load. The beam's weight is not what matters either — its support at posts or bearing walls is. And ridge boards are used on sloped roofs, which is exactly where the thrust the ties resist comes from.

Collar ties used to resist wind uplift should be spaced no farther apart than what, measured along the ridge?

• a.96 inches on center
• b.24 inches on center
• c.48 inches on center✓
• d.12 inches on center

Conventional framing provisions limit collar ties (minimum 1x4) to a maximum spacing of 4 feet (48 inches) on center along the ridge. Closer spacings of 12 or 24 inches exceed what is required, and 96 inches is well beyond the permitted maximum.2025 CA Residential Code §R802.4.6

CALCULATION: A common rafter runs horizontally 12 feet from the wall to the ridge and rises 9 feet. Ignoring overhang and cuts, what is the approximate rafter line length?

• a.18 feet
• b.15 feet✓
• c.13 feet
• d.21 feet

The rafter line length is the hypotenuse: the square root of (12 squared + 9 squared) = square root of (144 + 81) = square root of 225 = 15 feet. This is a 3-4-5 triangle scaled by 3. 13 feet ignores the rise, 18 and 21 feet overstate the diagonal.

CALCULATION: A gable roof has a 5:12 slope. If the horizontal run from the wall to the ridge is 24 feet, what is the rafter line length (rounded to the nearest foot, ignoring overhang)?

• a.25 feet
• b.29 feet
• c.24 feet
• d.26 feet✓

At a 5:12 slope, rise = run x 5/12 = 24 x 5/12 = 10 feet. The rafter length is the hypotenuse: square root of (24 squared + 10 squared) = square root of (576 + 100) = square root of 676 = 26 feet. 24 ignores the rise, 25 and 29 miscompute the diagonal.

CALCULATION: A building is 28 feet wide with a central ridge. Ignoring ridge-board thickness, what horizontal run does each common rafter span from the exterior wall to the ridge?

• a.21 feet
• b.28 feet
• c.14 feet✓
• d.7 feet

For a symmetric gable, each common rafter spans half the building width horizontally: 28 / 2 = 14 feet of run (the small ridge-board thickness is ignored here). 28 feet is the full width, 7 feet is a quarter, and 21 feet is three-quarters of the width.

On the jobsite, cutting, notching, or drilling the chords or webs of a prefabricated wood truss is:

• a.Allowed if done neatly with a sharp saw so the cut edges stay clean and the member keeps its shape
• b.Prohibited unless specifically permitted by the truss design or an engineer✓
• c.Allowed for the top chord only
• d.Allowed up to 25 percent of the member, the same way a solid sawn joist may be notched or bored

Truss members are engineered as a system, so no chord or web may be cut, notched, or drilled unless the truss design drawing or a registered design professional specifically allows it. Neat cutting, top-chord-only cutting, and a 25 percent rule do not apply to engineered trusses.2025 CA Residential Code §R802.10.4

What is the purpose of permanent lateral bracing on the web members of long-span roof trusses?

• a.To replace the need for a ridge board
• b.To prevent the slender web members from buckling and to stabilize the truss system✓
• c.To carry roofing weight directly to the ground through the web members instead of through the walls
• d.To serve as a walking surface for workers

Permanent web bracing ties the truss webs together so slender compression webs cannot buckle sideways and the truss system stays stable under load. It does not carry roofing to the ground, is not a walkway, and is unrelated to the ridge board, which trusses generally do not use.2025 CA Residential Code §R802.10.3

When a bird's-mouth seat cut is made where a rafter bears on the top plate, what limits how deep that notch may be cut?

• a.The remaining rafter depth above the notch must stay adequate; the seat cut should not over-notch the rafter✓
• b.The notch must equal the plate width plus 2 inches, so the seat laps past the outer face of the plate
• c.It may be cut to any depth to fit the plate, with the fit of the seat on the plate governing the cut
• d.It must remove exactly half the rafter, so the bearing seat and the remaining depth are always equal

A bird's-mouth seat cut removes material where the rafter sits on the plate, but enough rafter depth must remain above the notch to carry the load, so the cut is limited (commonly the notch does not exceed one-quarter to one-third of the rafter depth per design). Cutting to any depth, exactly half, or plate-width-plus-2 are not the governing limits.2025 CA Residential Code §R802.7

CALCULATION: A hip rafter runs diagonally across the plan corner of a roof. Compared with a common rafter having the same rise, the hip rafter is:

• a.Always half the length of the common rafter, since the corner splits that rafter's run into two equal parts
• b.Longer, because its horizontal run is the diagonal of the common rafter's run✓
• c.Shorter, because it is steeper, and a steeper pitch is assumed to reach the ridge over a shorter distance
• d.Exactly the same length, since both rafters start at the same wall line and finish at the same ridge height

A hip rafter travels along the diagonal of the corner, so its horizontal run is longer (the diagonal of the square formed by the common-rafter runs), making the hip rafter longer than a common rafter of the same rise. It is not shorter, equal, or half length; the diagonal run is what lengthens it.

On a wood I-joist, where may holes generally be cut, and which part must never be cut or notched?

• a.Only in the flange near supports
• b.Anywhere, because I-joists are solid members that carry load through their full depth like sawn lumber
• c.In the web per the manufacturer's hole chart; the flanges must never be cut or notched✓
• d.Anywhere in the flange; the web is off-limits because it is only a thin spacer between the two flanges

An I-joist carries bending through its top and bottom flanges, so the flanges must never be cut or notched; holes are allowed only in the web and only where the manufacturer's hole chart permits. Cutting flanges destroys the joist's capacity, and I-joists are not solid members.2025 CA Residential Code §R502.8.2

At the bearing ends of many wood I-joists, what component is often required to prevent web crushing or rotation?

• a.A thicker subfloor
• b.Web stiffeners (bearing blocks) and/or blocking panels✓
• c.Extra roofing felt
• d.Additional drywall screws driven into the joist ends to keep them from rotating on the wall

At supports, I-joist webs can be prone to crushing or the joist to rotation, so manufacturers often require web stiffeners (bearing blocks) fitted in the web and blocking panels or rim board at the ends. Roofing felt, thicker subfloor, and drywall screws do not address I-joist bearing.2025 CA Residential Code §R502.8.2

For laminated veneer lumber (LVL) and glued-laminated (glulam) beams, where must any holes or notches be located and sized?

• a.Holes are unlimited because the beam is engineered wood
• b.Only within 6 inches of a support at either end
• c.Only as permitted by the manufacturer or design professional✓
• d.Anywhere in the middle third of the beam's span

Because LVL and glulam are engineered products, holes and notches are allowed only where and as the manufacturer's literature or a design professional specifically permits, since unauthorized cuts can sharply reduce capacity. Blanket middle-third or near-support rules, or unlimited holes, do not apply.2025 CA Residential Code §R502.8.2

A glued-laminated (glulam) beam is stamped 'TOP' along one edge. Why must it be installed with that face up?

• a.So workers can read the grade stamp later, during framing inspection, without having to crawl underneath a beam that is already installed
• b.Only for appearance, so the smoother, better-looking laminated face of the beam ends up where it is seen from the room below
• c.Because the beam is manufactured with camber and higher-grade laminations to be on the correct side for the load✓
• d.To show the brand logo, so the manufacturer's mark on the beam stays visible to everyone on the job after the framing is complete

Glulams are built with a slight upward camber and with stronger tension laminations placed for the intended loading, so installing the 'TOP' edge up puts the camber and lamination layout in the correct orientation to resist load and deflection. Logo visibility, appearance, and reading the stamp are not the structural reason.

What minimum bearing length is commonly required at the ends of engineered wood floor members unless the manufacturer specifies otherwise?

• a.1/2 inch, treating the end bearing as a nominal contact only
• b.4 inches minimum always, applied as one fixed rule for every support
• c.No bearing is needed if hangers are used to carry the reaction
• d.About 1-1/2 inches on wood or metal (and more on masonry), per the manufacturer✓

Engineered floor members typically need on the order of 1-1/2 inches of end bearing on wood or metal (and more on masonry or concrete), following the manufacturer's tables, so the reaction is safely delivered. A 1/2 inch is too little, a flat 4-inch rule is not universal, and hangers still require adequate seat or nailing capacity.2025 CA Residential Code §R502.6

At the ends of I-joists that rest on a wall, a continuous member closing the joist ends and transferring vertical/lateral load is called what?

• a.A collar tie
• b.A ledger bolted to the face of a wall to carry the joist ends
• c.A rim board (rim joist)✓
• d.A purlin

A rim board (rim joist) runs continuously along the ends of I-joists, closing the floor, providing bearing for the wall above, and transferring vertical and lateral loads. A ledger attaches a structure to a wall, a collar tie is a roof member, and a purlin supports rafters.2025 CA Residential Code §R502.8.2

Where a concentrated load (such as a post from above) bears down over an I-joist at a support, what is often installed to carry that load past the joist without crushing it?

• a.A layer of building paper set on top of the joist at the bearing point
• b.Extra roofing nails driven through the top flange of the joist at the support
• c.A single drywall screw through the joist flange at the bearing point
• d.Squash blocks (vertical blocks slightly taller than the joist depth) beside the joist✓

Squash blocks are short vertical members set beside the I-joist at a bearing point, cut just proud of the joist depth so the concentrated load bypasses the I-joist web and transfers directly to the support below. A screw, roofing nails, or building paper cannot carry a concentrated vertical load.2025 CA Residential Code §R502.8.2

CALCULATION: An engineered LVL header is specified as a 3-1/2 inch wide member built up from plies that are each 1-3/4 inch thick. How many plies are laminated together?

• a.1 ply
• b.3 plies
• c.4 plies
• d.2 plies✓

Total width divided by ply thickness: 3.5 / 1.75 = 2 plies. A single 1-3/4 inch ply gives only 1-3/4 inch, three plies give 5-1/4 inch, and four plies give 7 inch, none of which equals the specified 3-1/2 inch width.

Engineered rim board is often chosen over solid sawn lumber at the perimeter of an I-joist floor mainly because it:

• a.Is fire-rated by itself, so the perimeter of the floor needs no other protection where the rim closes the ends of the joists
• b.Is always cheaper than solid sawn lumber of the same depth, whatever the size of the floor and the length of its perimeter
• c.Needs no fasteners, because friction between the tight ends of the joists and the panel is enough to hold it in place
• d.Matches the depth of the I-joists and provides consistent, rated vertical load transfer around the floor✓

Engineered rim board is manufactured to match I-joist depths and to carry the rated vertical and lateral loads uniformly around the floor perimeter, avoiding the shrinkage and depth-mismatch problems of solid lumber. Cost, fastener-free installation, and inherent fire rating are not the governing reasons.2025 CA Residential Code §R507.5

Compared with solid-sawn joists, why are field notches and unauthorized holes especially damaging to engineered wood products such as I-joists and LVL?

• a.They gain strength when cut, because relieving the wood at the notch lets the material that is left share the load between the flanges more evenly
• b.They are made of steel
• c.They are unaffected by cuts, since the adhesive bond between the laminations spreads the load around any opening that is left in the member
• d.Their strength depends on thin engineered flanges/laminations, so unauthorized cuts remove critical load-carrying material✓

Engineered products concentrate their strength in thin, carefully placed flanges and laminations, so an unauthorized notch or hole removes exactly the material carrying the load and can cause sudden failure, unlike solid lumber that has some reserve. They are not steel, are certainly affected by cuts, and never gain strength from cutting.2025 CA Residential Code §R502.8

On braced/shear walls, code requires a plate washer at each anchor bolt between the sill plate and nut. A common minimum size is:

• a.3 inch by 3 inch by 0.229 inch✓
• b.1 inch by 1 inch by 1/16 inch
• c.No washer is needed if a nut is used
• d.2 inch round by 1/8 inch

For braced-wall sill anchorage in seismic areas, the code commonly requires a plate washer at least 3 inch by 3 inch by 0.229 inch thick under the nut, so seismic uplift cannot pull the sill over the bolt head. A tiny 1x1 or thin round washer is inadequate, and a nut alone does not spread the load.2025 CA Residential Code §R602.11.1

For a bolted sill plate, the code requires a minimum number of anchor bolts per plate piece and a limit on bolt distance from plate ends. Which statement is correct?

• a.End distance does not matter
• b.At least two bolts per plate piece, with a bolt located near each end (commonly within 12 inches, but not less than about seven bolt diameters, of each end)✓
• c.One bolt per plate is always enough
• d.Bolts may be placed only at the exact center of each plate piece, where the anchor sits farthest from the ends and is least likely to split the wood as it is drawn down

Each sill-plate piece must have at least two anchor bolts, with one near each end (typically within 12 inches of the end but not closer than roughly seven bolt diameters), so short pieces cannot pivot or lift free. One bolt, center-only placement, and ignoring end distance all violate the anchorage rules.2025 CA Residential Code §R403.1.6

CALCULATION: A sill plate on a 30-foot wall uses anchor bolts spaced at the 6-foot maximum, with a bolt required near each end. Approximately how many anchor bolts are needed along that wall?

• a.4 bolts
• b.10 bolts
• c.6 bolts✓
• d.5 bolts

With bolts at 6 feet on center over 30 feet, the spacing gives 30/6 = 5 intervals, which needs 5 + 1 = 6 bolts to also place one near each end. Four or five bolts would leave spacing or end distances too great, and ten bolts far exceeds the 6-foot maximum spacing.

In a wood-framed building, what is the PRIMARY role of a floor or roof diaphragm in the lateral system?

• a.To carry only gravity floor loads down to the joists and bearing walls
• b.To collect lateral (wind/seismic) forces and transfer them horizontally to the shear walls✓
• c.To insulate the floor cavity and slow heat loss between the levels above
• d.To provide the finished floor surface that the occupants walk on daily

A diaphragm is the horizontal sheathed floor or roof plane that collects wind and seismic forces and distributes them to the vertical shear walls that carry them to the foundation. Gravity load, finish surface, and insulation are separate functions, not the diaphragm's lateral role.

At the ends of a shear wall, why is blocking installed at horizontal panel joints in a 'blocked' shear wall?

• a.To hold insulation in place between the studs so that it cannot slump away from the sheathed face of the wall over time
• b.To hang the drywall, giving the interior finish a solid backing wherever the panel joints happen to fall on the wall
• c.To act as fireblocking only, closing off the stud cavity so that fire cannot travel up behind the wall sheathing
• d.To provide continuous framing so panel edges can be nailed and shear can transfer across the joint✓

In a blocked shear wall, solid blocking behind horizontal panel joints gives every panel edge continuous framing to nail to, allowing the wall to reach its higher rated shear capacity by transferring load across the joint. Insulation support, fireblocking, and drywall hanging are not the structural purpose of shear-wall edge blocking.2025 CA Residential Code §R602.10.8

In a continuous load path for lateral loads, what is the main job of metal straps that connect wall framing across a floor level (stacked walls)?

• a.To level the floor
• b.To tie upper and lower wall segments together so uplift and overturning forces pass continuously to the foundation✓
• c.To carry plumbing across floors, holding the risers tight against the framing at the point where they pass through the floor level
• d.To provide a nailing surface for baseboard and other trim in all the places where the finish carpenter cannot find solid framing

Straps across a floor level splice the upper wall to the lower wall so uplift and overturning tension travels down through each story to the foundation, maintaining a continuous load path. Leveling, plumbing support, and baseboard nailing are not the purpose of these tension straps.2025 CA Residential Code §R602.10.6

In a seismic retrofit of an older house with a raised foundation, what two upgrades are MOST commonly added to the cripple wall and sill to resist earthquake movement?

• a.Larger windows and doors in the cripple wall, opening it up so that the space under the floor is easier to reach and to ventilate
• b.New roofing and gutters
• c.Structural panel sheathing on the cripple wall and anchor bolts (or plates) connecting the sill to the foundation✓
• d.Interior paint and trim

The classic soft-story cripple-wall retrofit adds wood structural panel bracing to the short cripple wall and anchor bolts or foundation plates tying the sill to the concrete, so the house cannot slide off or the cripple wall collapse in a quake. Roofing, windows, and paint do not address this lateral weakness.2025 CA Existing Building Code

What is the main purpose of a hold-down (tie-down) anchor at the end post of a narrow shear wall?

• a.To resist the uplift/overturning tension generated at the wall end and anchor it to the foundation✓
• b.To seal the wall against air leaks at the sill so conditioned air stays inside
• c.To provide gravity bearing for the roof load coming down through the end post
• d.To level the top plate so the wall framing sits true before sheathing goes on

A hold-down connects the end post (chord) of a shear wall to the foundation and resists the tension uplift that lateral load creates as the wall tries to overturn, which is critical on narrow walls with high overturning. Leveling, gravity bearing, and air sealing are not the hold-down's function.2025 CA Residential Code §R602.10.6.2

A 'collector' or 'drag strut' in a lateral system does what?

• a.Serves as a decorative beam, left exposed along the ceiling line to dress up the room where the diaphragm meets the wall
• b.Provides gravity support only, picking up the floor or roof framing that happens to land between the shear walls below
• c.Collects rainwater from the roof and carries it along the edge of the building to the downspouts at the corners of the wall
• d.Gathers diaphragm forces and 'drags' them into the shear wall that is shorter than the diaphragm edge✓

A collector (drag strut) is a framing member that gathers the lateral force along a diaphragm edge and delivers it into a shear wall that does not run the full length of that edge, keeping the load path continuous. It has nothing to do with rainwater, gravity-only support, or decoration.2025 CA Residential Code §R602.10

To transfer shear from a diaphragm or wall into the framing, the connection of sheathing to the boundary members depends MOST on which factor?

• a.The nail size, spacing, and edge distance along the boundary✓
• b.The brand of the lumber
• c.The paint on the studs, since a coated face lets the sheathing slide instead of gripping
• d.The color of the sheathing, because a darker panel is taken as the higher-strength grade

Shear transfer at a boundary is governed by the fastening: nail size, spacing, and adequate edge distance along the boundary members determine how much shear the connection can move without splitting or pulling through. Sheathing color, lumber brand, and paint have no effect on shear transfer.2025 CA Residential Code §R602.3.1

Behind exterior cement plaster (stucco) applied over wood-based sheathing, how many layers of water-resistive barrier does the code generally require?

• a.Only a vapor barrier on the inside
• b.Two layers of a water-resistive barrier (for example, two layers of Grade D paper)✓
• c.One layer
• d.No barrier if the stucco is thick enough, since the plaster itself is treated as the drainage plane of the wall

Of these options, two layers is the code route: fresh stucco bonds to and can compromise the first layer, so the second layer maintains a continuous drainage plane. R703.7.3 also allows 60-minute Grade D paper separated from the stucco, and IECC marine climate zones add drainage, but neither appears here. One layer, no barrier, and an interior-only vapor barrier do not meet R703.7.3.2025 CA Residential Code §R703.7.3