CSLB C-13 Fencing (Trade Exam) — All Questions
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137 questions
How long should untreated square California redwood posts last, according to the bulletin?
- a.4 to 20 years, depending on climate✓
- b.30 to 40 years, anywhere in the nation
- c.1 to 2 years, in a mild climate
- d.50 to 100 years, in a dry climate
The bulletin gives 4 to 20 years for untreated square California redwood posts. Thirty to forty years is the figure for pine posts pressure treated for ground contact, and the other ranges are not given.USDA Forest Products Laboratory, Protecting Wood Fences for Yard and Garden
A buyer sees a bright green coating on lumber and assumes it is pressure treated. What does the bulletin say about bright coatings applied for shipping?
- a.They are required by state law on all fence posts
- b.They show that preservative reached deep into the wood
- c.Surface treatments that give no long-term protection✓
- d.They prove the lumber is rated for ground contact use
The bulletin says shipping coatings are only surface treatments and give no long-term protection, and that wood color cannot show the quality of treatment. They do not show penetration or ground-contact rating.USDA Forest Products Laboratory, Protecting Wood Fences for Yard and Garden
Which fence part needs more protection from decay, according to the bulletin?
- a.Post caps of any material
- b.Vertical boards of any species
- c.Horizontal rails✓
- d.Pickets and their fasteners
Horizontal rails need more protection from decay than vertical boards because water enters their cracks and joints and is trapped. Boards and pickets are face parts that need less.USDA Forest Products Laboratory, Protecting Wood Fences for Yard and Garden
Crushed rock around a wood post can have what drawback, according to the bulletin?
- a.It rots the post faster in dry soil
- b.It makes the post heavier and harder to straighten
- c.It can trap a pool of water at the post base in clay✓
- d.It prevents any termite attack from reaching the post
Crushed rock can improve drainage in light soils, but in clay soils it can trap a pool of water around the base of the post. It does not rot a post faster in dry soil, it does not make the post harder to straighten, and termites can go through rock fill, so it does not stop them.USDA Forest Products Laboratory, Protecting Wood Fences for Yard and Garden
Which fastener choice does the bulletin recommend for a wood fence?
- a.Galvanized nails with no coating at the head
- b.Plain steel staples without any added coating
- c.Bare iron nails, which are strong and cheap
- d.Corrosion-resistant nails, such as stainless steel✓
Iron nails rust rapidly and discolor the wood, so the bulletin recommends aluminum or stainless steel nails. Bare iron and plain steel are what to avoid, and the bulletin does not recommend galvanized fasteners in that passage.USDA Forest Products Laboratory, Protecting Wood Fences for Yard and Garden
When should a water-repellent preservative be applied to precut wood?
- a.After cutting, since a later saw cut exposes bare wood✓
- b.At the lumberyard, before the wood is delivered
- c.After the fence has stood for a full year
- d.Before the wood is cut, so the cuts are all sealed
Water-repellent preservatives are applied after cutting, because a later saw cut exposes unprotected wood. Applying before cutting loses the treatment at the cut, and the treatment is meant for above-ground wood, not for posts in the ground.USDA Forest Products Laboratory, Protecting Wood Fences for Yard and Garden
A homeowner wants to use chipped old treated posts as garden mulch. What does the air district notice say?
- a.It is fine if the posts are older than ten years
- b.Treated wood waste may not be chipped or burned✓
- c.It is fine in a vegetable garden but not in a lawn
- d.It is fine if the chips are composted for a year first
The notice says treated wood may not be burned or chipped at any time, and that mulch from the chips can put toxic compounds into soil and groundwater. The age of the posts, composting the chips and the kind of garden are not exceptions the notice names, because the preservative stays in the wood.San Joaquin Valley APCD, Chemically Treated Wood Waste Disposal (AB 332)
When did the law that restored alternative management standards for treated wood waste, Assembly Bill 332, get signed, according to the air district notice?
- a.June 30, 2019
- b.January 1, 2015
- c.December 31, 2024
- d.August 31, 2021✓
The notice says AB 332 was signed into law on August 31, 2021, and took effect immediately as an urgency statute. June 30, 2019, January 1, 2015 and December 31, 2024 are not the signing date.San Joaquin Valley APCD, Chemically Treated Wood Waste Disposal (AB 332)
What does Caltrans require for the length of a treated line post or brace, and of any other post?
- a.5 feet for a line post, 7 feet for any other post
- b.7 feet for a line post or brace, 8 feet for any other post✓
- c.8 feet for a line post, 10 feet for any other post
- d.6 feet for a line post, 6 feet for any other post
Each line post and brace is 7 feet long and any other post is 8 feet long. The other pairs do not match the specification.Caltrans 2024 Standard Specifications 80-2.02C(3)
A 7-foot-high wood fence is built around a yard with no pool. What does the building code say about a permit?
- a.A permit is required for a fence of this height
- b.A permit is required, because the material is wood
- c.Exempt from a building permit, since it is not over 7 feet✓
- d.A permit is required, because it is over 6 feet tall
The list exempts fences, other than swimming pool barriers, not over 7 feet high, and 7 feet is not over 7 feet. A permit is not required because the fence is wood or because it is over 6 feet, since the limit is 7 feet, and a permit is not required at this height either.2025 CBC 105.2
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What is the maximum knot size the Caltrans specification allows on any face of an untreated post?
- a.2 inches✓
- b.4 inches
- c.1/2 inch
- d.No knots larger than 1 inch
Post knots must be sound, tight, well spaced and not over 2 inches on any face. Four inches is a cross-section dimension, and half an inch and 1 inch are stricter limits than the specification sets.Caltrans 2024 Standard Specifications 80-2.02C(2)
A customer wants to sell a stack of old treated posts as firewood. What does the air district notice say?
- a.It may be sold as firewood if it is labeled for fire pits
- b.Chemically treated wood waste may not be sold or offered as firewood✓
- c.It may be sold as firewood if the buyer will use a fireplace
- d.It may be sold as firewood if the posts are dried first
The notice says not to sell or offer chemically treated wood waste for use as firewood, and that it may not be burned. Drying, a fireplace or a fire-pit label does not remove the preservative.San Joaquin Valley APCD, Chemically Treated Wood Waste Disposal (AB 332)
How does the aluminum-fence instruction say to keep layout accurate when digging post holes?
- a.Dig all holes at one depth with no check
- b.Dig only 4 or 5 holes at a time✓
- c.Dig the gate holes first and the rest later
- d.Dig the full run of holes before setting any post
The instruction says to dig only 4 to 5 holes at a time and set posts and panels as you go. Digging all holes first loses the layout when holes shift, and digging only gates or ignoring checks is not the method.Aluminum fence maker installation instructions, Step 3
What is the minimum diameter of a post hole for an aluminum fence in that instruction?
- a.3 inches
- b.6 inches✓
- c.12 inches
- d.24 inches
The instruction digs post holes with a minimum 6-inch diameter, below the local frost line. Three inches is too small for a post and concrete, and 12 and 24 inches are not the stated minimum.Aluminum fence maker installation instructions, Step 2
About how much concrete does each aluminum-fence hole require, per that instruction?
- a.About 200 to 300 pounds
- b.About 5 to 10 pounds
- c.About 100 to 120 pounds
- d.About 40 to 60 pounds✓
The instruction says each hole will require approximately 40 to 60 pounds of concrete. Five to ten pounds is far too little, and the larger ranges would suit a vinyl gate post.Aluminum fence maker installation instructions, Step 2
How is an aluminum panel cut to fit a wall mount?
- a.Notch each rail 1/2 inch deep at the wall end
- b.Use the standard panel and trim 1 inch from the wall side
- c.Measure to the outside of the mount and subtract 3/4 inch
- d.Measure to the inside of the mount, add 3/4 inch; no notching✓
The instruction measures from the post to the inside of the wall mount, adds 3/4 inch, and says no rail notching is needed in wall mounts. Subtracting, trimming or notching is not the method.Aluminum fence maker installation instructions, Step 5
How much is removed from each rail when notching an aluminum panel cut for an end post?
- a.A 3/4-inch by 1/8-inch section✓
- b.Nothing, rails are cut square
- c.A 1-1/2-inch by 1/2-inch section
- d.A 1/4-inch by 1/4-inch section
The instruction removes a 3/4-inch by 1/8-inch section from all rails, and at corner posts an additional 1/2-inch piece. The other sizes are not stated, and rails are notched, not left square.Aluminum fence maker installation instructions, Step 4
What does ASTM F2408 cover?
- a.Coated tubular picket fence of galvanized steel✓
- b.Solid-bar wrought iron vertical bar fence systems
- c.Wood picket fence systems with steel rails
- d.Vinyl picket fence systems for residential yards
The specification covers coated tubular picket ornamental fence systems fabricated from galvanized steel, and it does not apply to vertical bar systems of solid bar or wrought iron. Vinyl and wood are covered by other documents.ASTM F2408 scope (store abstract)
Which exterior powder coatings does ASTM F2408 describe for ornamental fence components?
- a.Polyester, or epoxy-and-polyester combinations✓
- b.Wax coatings applied to the steel by brush
- c.Zinc dust paint applied by roller
- d.Linseed oil stain applied to bare steel
The scope says powder coatings on the exterior are polymer material: polyester or epoxy-and-polyester combinations. Wax, zinc dust paint alone and linseed oil are not those coatings.ASTM F2408 scope (store abstract)
A 67-inch steel post is installed so that it stands 52 inches above ground. How far is it in the ground?
- a.52 inches
- b.15 inches✓
- c.119 inches
- d.67 inches
67 − 52 = 15 inches in the ground. Fifty-two inches is the part above ground, 67 is the whole post, and 119 adds the two numbers.Composite steel-post maker in-ground post instructions
In a slat kit with 24-inch slats, what is the post spacing, using the maker's rule of slat width plus 1/2 inch?
- a.24 inches
- b.25 inches
- c.23-1/2 inches
- d.24-1/2 inches✓
The post spacing equals the slat width plus 1/2 inch, so 24.5 inches. Twenty-four inches leaves no room for the slats to slide, 25 inches adds a full inch, and 23-1/2 inches subtracts instead of adds.Composite steel-post maker in-ground post instructions
Why does the steel post maker say to put wood blocks between posts?
- a.To mark where the gate hangs on the finished fence
- b.To keep the concrete from setting before the panels go in
- c.To raise the post above the frost line in the hole
- d.To carry the weight of panels or slats during installation✓
The instruction positions wood blocks between posts to support panel or slat weight during installation. The blocks do not affect concrete setting, frost depth or gate position.Composite steel-post maker in-ground post instructions
Under the 2025 California Building Code, what is the minimum height of required guards in the general rule?
- a.48 inches
- b.60 inches
- c.42 inches✓
- d.36 inches
Required guards are not less than 42 inches high. Thirty-six inches is the lower edge of the 4-3/8-inch sphere band, 48 inches is not the rule, and 60 inches is the pool enclosure height.2025 CBC 1015.3
What size sphere may not pass through guard openings between 36 and 42 inches above the walking surface, under the exception?
- a.A sphere of 4-3/8 inches✓
- b.A sphere of 4 inches
- c.A sphere of 21 inches in diameter
- d.A sphere of 6 inches
From a height of 36 to 42 inches, guards shall not have openings that allow passage of a sphere 4-3/8 inches in diameter. The 4-inch rule applies below that band, 6 inches is the stair triangle, and 21 inches is for equipment access areas.2025 CBC 1015.4
An ornamental fence is built around a single-family-home pool. What clear gap between pickets would let a 4-inch sphere pass and violate Section 115923?
- a.A gap of 3 inches
- b.A gap of 4 inches or more✓
- c.A gap of 3-3/4 inches between the pickets
- d.A gap of 2-1/2 inches
The statute does not allow gaps that let a sphere of 4 inches or larger pass, so a clear gap of 4 inches or more fails. Gaps of 3-3/4, 3 and 2-1/2 inches stop the sphere.Cal. Health & Safety Code 115923(d)
A crew levels an aluminum fence that was dry-packed. When must the leveling be done?
- a.After the first rain
- b.After 2 weeks of curing
- c.It is not done, since dry-packed posts stay as set
- d.The same day✓
The instruction says if you dry-packed your concrete, leveling should be done the same day. A two-week wait, rain or no leveling would leave posts locked in the wrong position.Aluminum fence maker installation instructions, Step 7
Which standard covers vinyl-coated chain link fabric, as opposed to the framework?
- a.ASTM F2408
- b.ASTM F668✓
- c.ASTM F2200
- d.ASTM F1043
ASTM F668 covers polymer-coated chain-link fabric. F1043 is the framework standard, F2408 covers galvanized steel tubular picket ornamental fence, and F2200 covers automated vehicular gates.ASTM F668, F1043, F2408 and F2200 scopes (store abstracts)
The vinyl manufacturer says to tape the ends of a rail in what situation?
- a.When the rail is stored outdoors before installation
- b.When the rail goes into a post to be filled with concrete✓
- c.When the rail is cut in the field to a shorter length
- d.When the rail is painted to match a finished color
The manual says to tape the ends of any rail inserted into a post that is to be filled with concrete, to prevent concrete seepage into the rail. Cutting a rail, storing it outdoors and painting it have nothing to do with seepage, so none calls for taping.Vinyl fence maker installation manual, Install Bottom Rail
How many pieces of rebar does the vinyl manual use in each hinge, latch and end post, and what size?
- a.Two pieces of 3/4-inch rebar
- b.One piece of 1/4-inch rebar
- c.Four pieces of 1-inch rebar
- d.Two pieces of 1/2-inch rebar✓
The manual uses two pieces of 1/2-inch rebar in each hinge, latch and end post, held in opposite corners by separator clips. The other counts and sizes are not given.Vinyl fence maker installation manual, Solidify Gate Posts
How far from the top of the post does the vinyl manual say the rebar should extend?
- a.To the bottom of the hole, not up the post
- b.To about 6 feet below the top of the post
- c.To about 12 inches from the top of the post✓
- d.To the very top of the post, flush with the cap
The rebar extends from the bottom of the hole to approximately 12 inches from the top of the post. Stopping at the bottom of the hole, ending 6 feet below the top, and running flush with the cap are each different from the manual, which stops about 12 inches short of the top.Vinyl fence maker installation manual, Solidify Gate Posts
How much concrete does the manual's table give for a 5 x 5 end post filled with concrete at a 6-foot fence?
- a.240 pounds✓
- b.285 pounds
- c.100 pounds
- d.140 pounds
The table gives 240 pounds for a 5 x 5 end post filled with concrete at 6 feet. One hundred forty pounds is the line post, 285 is the gate post, and 100 is the 4 x 4 line figure.Vinyl fence maker installation manual, Concrete Usage for Posts
What post-center spacing does the manual show for a 4 x 4 traditional picket style with 3-inch pickets?
- a.72 inches✓
- b.60 inches
- c.73 inches
- d.96 inches
For the 4 x 4 post with 3-inch pickets the manual shows 72 inches. Ninety-six inches is another style, 73 inches is the 5 x 5 figure for that style, and 60 inches is not shown.Vinyl fence maker installation manual, Traditional Picket Fence
In the manufacturer's wind table for exposure B, what maximum post spacing goes with a 24-inch footing?
- a.56 inches
- b.97 inches
- c.88 inches
- d.66 inches✓
Exposure B with a 24-inch footing allows 66 inches. Ninety-seven inches is exposure B with a 30-inch footing, 88 is exposure C with 36 inches, and 56 is exposure D with 30 inches.Vinyl fence maker installation manual, Maximum Post Spacing and Footing Dimensions
In the wind table, what happens to the allowed post spacing if the footing is made shallower at the same exposure?
- a.The maximum spacing is unchanged
- b.The footing depth does not appear in the table
- c.The maximum spacing gets larger
- d.The maximum spacing gets smaller✓
At exposure B, 30 inches allows 97 inches and 24 inches allows 66, and at exposure C, 36 inches allows 88 and 30 inches allows 68. A shallower footing means closer posts, so the spacing gets smaller, not larger or unchanged, and footing depth is in the table.Vinyl fence maker installation manual, Maximum Post Spacing and Footing Dimensions
What does the vinyl manual say to do when a vinyl post must be installed on an existing concrete slab?
- a.Core drill, set a steel post in cement and sleeve the vinyl post over it✓
- b.Screw the vinyl post to the slab surface with lag bolts
- c.Glue the vinyl post to the slab surface with caulk
- d.Set the vinyl post in a bed of dry sand on the slab
The manual's method is to core drill, set a galvanized steel post in hydraulic cement and slide the vinyl post over the steel, with the steel going at least halfway up. Lag bolts, sand and caulk are not described.Vinyl fence maker installation manual, Alternative Fence Installations
What steel post size does the manual use inside a 4-inch vinyl post on a slab?
- a.1/2 inch outside diameter
- b.3 inch outside diameter
- c.1-7/8 inch outside diameter
- d.1-5/8 inch outside diameter✓
A 4-inch vinyl post is set over a 1-5/8-inch OD steel post, and a 5-inch vinyl post over a 1-7/8-inch OD steel post. Three inches and 1/2 inch are not the sizes.Vinyl fence maker installation manual, Alternative Fence Installations
What problem does the manual warn about when concrete is used inside a vinyl post in a freeze-thaw climate?
- a.Post cracking over time, with no warranty coverage✓
- b.Sagging of the top rail under its own weight
- c.Loss of the gate latch spring over several years
- d.Rust forming on the concrete inside the post
The manual cautions that in climates with freeze-thaw cycles this method could result in post cracking over time, not covered by the warranty. Rust, latch loss and rail sagging are not the stated problem.Vinyl fence maker installation manual
How much clearance does the manual require under the bottom rail of a gate on level ground?
- a.6 inches
- b.1/4 inch
- c.2 inches✓
- d.1/2 inch
The manual says a gate requires 2 inches of clearance under the bottom rail on level ground. Half an inch and a quarter inch are less than the clearance the manual requires, and six inches is too much for most uses.Vinyl fence maker installation manual, Gates
What size drain holes does the vinyl manual say to drill in a field-built gate's bottom rail?
- a.1/4 inch✓
- b.3/4 inch
- c.2 inches
- d.1 inch
The manual says to ensure 1/4-inch drain holes are drilled in the bottom rail of a gate built in the field. One inch is the rail-end expansion gap, 3/4 inch is the latch gap, and 2 inches is the ground clearance.Vinyl fence maker installation manual, Gates
In the post-and-rail style section of the vinyl manual, what hinge-side and latch-side gaps does it give for the gate?
- a.1 inch at the hinge side and 3/4 inch at the latch side
- b.No gap on either side of the gate leaf
- c.3 inches on both sides of the gate leaf
- d.1-1/2 inches at the hinge and 1-1/4 inches at the latch✓
The post-and-rail section of the manual allows a 1-1/2-inch gap on the hinge side and 1-1/4 inches on the latch side, while the picket styles allow 1 inch and 3/4 inch, so the style named in the question decides. Three inches and none are not given.Vinyl fence maker installation manual, Hang Gate/Install Hardware
What is the composite maker's recommended section width on center of the posts for its fence?
- a.8 feet (96 inches)✓
- b.6 feet (72 inches)
- c.4 feet (48 inches)
- d.10 feet (120 inches)
The maker says sections should be 8 feet (96 inches) wide on center of the posts. Six feet is the fence height, and 10 and 4 feet are not stated.Composite maker knowledge base, installing the fence
What expansion gap does the composite maker specify between slat and post?
- a.40 mm
- b.20 mm
- c.0 mm
- d.4 mm✓
The maker says an expansion gap of 4 mm should be left between the fence slat and post. Twenty millimeters is the clearance at the top of the panel, forty is not stated, and zero leaves no room for expansion.Composite maker installation guide (metric)
How many slats make up a standard 1.8 m (6 ft) fence height in the same guide?
- a.12✓
- b.18
- c.24
- d.6
The guide gives 12 slats for a standard 1.8 m (6 ft) height. Six slats are too few for that height, and 18 or 24 slats are more than the guide lists.Composite maker installation guide (metric)
Center-to-center post spacing for a panel system equals what?
- a.Panel length times two, for a double panel
- b.Panel length minus the gaps at each end
- c.Panel length plus gaps plus post width✓
- d.The post width alone, with no panel length
The spacing is the panel length plus the expansion gaps plus the width of the post, as in the maker's 1,774 mm plus 100 mm. Subtracting, doubling and using the post width alone do not describe it.Composite maker installation guide (metric)
In the same guide, how are slats cut to follow a slope?
- a.Mitred to the slope, or the bottom slat ripped to it✓
- b.Cut square and left to overhang the posts
- c.Left uncut, with the posts cut off square instead of the slats
- d.Bent by heating them over a flame
The guide says slat ends can be mitred to the angle of the slope, or the bottom slat can be ripped to the slope with the bottom panel cap in place. Leaving overhangs, bending and cutting posts are not the methods.Composite maker installation guide (metric)
How should composite slats be stored, according to the maker?
- a.Leaning on end against a wall in the shade
- b.Flat and level, on supports 500 mm apart✓
- c.Bundled upright in the sun until needed
- d.Stacked directly on bare soil beside the job
The guide stores products flat and level, supported above the ground at 500 mm intervals, with bearers no more than 500 mm apart so boards do not bow. Leaning, ground contact and upright bundles would warp or soil them.Composite maker installation guide (metric), Material Storage
What does the maker say about moving composite slats?
- a.Lift and set down; never slide slats on each other✓
- b.Slide them across each other to save time
- c.Throw them onto the pile near the posts
- d.Drag them behind a truck to the fence line
The guide says to lift the slats and set them down, and not to slide slats against each other or drag equipment across them. Sliding, dragging and throwing damage the surface.Composite maker installation guide (metric), Material Handling
What blade does the maker recommend for the cleanest cuts in composite slats?
- a.A 12-tooth framing blade for fast cutting
- b.A masonry abrasive blade for dense material
- c.A chain saw bar for long rip cuts
- d.A thin kerf 40-tooth finish blade✓
The guide recommends a thin kerf 40-tooth alternate top bevel finish blade. A coarse framing blade, an abrasive blade and a chain saw tear or chip the surface.Composite maker installation guide (metric), Recommended Tools
How does a hollow composite post mount over a concrete pad, according to one composite maker?
- a.It is nailed to the pad surface with masonry nails
- b.It sleeves over a steel or wood support, or is embedded✓
- c.It is set loose on the pad and held by its weight
- d.It is glued directly to the pad with construction adhesive
The maker says its hollow posts can be sleeved over steel or wood supports or embedded in the pad or wall, after checking that the pad can support a fence and wind. Glue, nails and a loose post cannot resist wind loads.Composite maker knowledge base, installing a fence post
What does the aluminum bottom rail do in a composite fence system?
- a.It adds strength so the fence does not sag✓
- b.It provides the gate latch for the walk gate
- c.It replaces the posts between the sections
- d.It holds the post caps on top of the posts
The aluminum bottom rail provides strength to protect against sagging, and composite bottom rail covers sleeve over it. It does not hold caps, replace posts or provide the latch.Composite maker knowledge base, installing the fence