Planning, Estimating, Permits, and Contract Law
Planning and Estimating is about 18 percent of the official CSLB C-27 outline, covering project planning, hardscape, drainage and irrigation design, and project estimating. This chapter works the arithmetic that appears on the examination, with a calculator provided at the test center, and then covers the permits a landscape project triggers and the California contract rules that apply to residential landscape work. The volume conversions in the first section are the single most repeated calculation in the whole topic, so learn the two forms and you will not have to think about them again.
Volume and Area Takeoff, Worked
Bulk materials are sold by the cubic yard, and there are 27 cubic feet in a cubic yard. So the general formula is length times width times depth, all in feet, divided by 27. Work it: a bed 30 feet by 18 feet covered 6 inches deep is 30 times 18 times 0.5, which is 270 cubic feet, divided by 27, which is exactly 10 cubic yards. A patio 12 feet by 15 feet poured 4 inches thick is 12 times 15 times one third, which is 60 cubic feet, divided by 27, which is about 2.2 cubic yards. A slab 14 feet by 20 feet at 4 inches is 14 times 20 times one third, or 93.3 cubic feet, divided by 27, which is about 3.5 cubic yards. Soil imported for a bed 40 feet long, 10 feet wide, and 9 inches deep is 40 times 10 times 0.75, which is 300 cubic feet, divided by 27, or about 11.1 cubic yards. A trench 60 feet long, 2 feet wide, and 18 inches deep yields 60 times 2 times 1.5, which is 180 cubic feet, divided by 27, or about 6.7 cubic yards before bulking. The second form of the same formula is faster when you have an area in square feet and a depth in inches: multiply the area in square feet by the depth in inches and divide by 324. Mulching 900 square feet at 3 inches deep is 900 times 3 divided by 324, which is about 8.3 cubic yards. A bed 24 by 15 feet, which is 360 square feet, at 4 inches deep is 360 times 4 divided by 324, or about 4.4 cubic yards. Areas follow ordinary geometry. A rectangular lawn 45 by 60 feet is 2,700 square feet. A circular bed 20 feet in diameter has a 10-foot radius, so its area is 3.14 times 10 times 10, or about 314 square feet, and a circular lawn with a 12-foot radius is 3.14 times 144, or about 452 square feet. A triangular corner bed with an 18-foot base and a 12-foot height is one half times 18 times 12, or 108 square feet. Two conversions round this out. Bulk material sold by weight converts through its unit weight: decomposed granite quoted at roughly 1.4 tons per cubic yard means 9 cubic yards is about 12.6 tons. And excavated soil occupies more volume in the truck than it did in the ground, because excavation breaks up its compacted structure and introduces void space, a phenomenon called bulking or swell.
Plans, Scale, and Quantity Takeoff
A quantity takeoff is prepared from the plans and the specifications read together, because the plans show what and where while the specifications show quality, materials, and standards. A landscape plan's legend or symbol schedule identifies each symbol and the plant it represents, and a plant list entry such as QUAG, 24 box, 7 conveys a species abbreviation, a container size, and the quantity of that plant. Scale converts plan dimensions to real ones. At a scale of one inch equals ten feet, a bed measuring 4 inches on the plan is 40 feet long. At a scale of one eighth inch equals one foot, a wall measuring 5 inches on the plan is 5 divided by 0.125, which is 40 feet. Plant and material counts follow spacing geometry. One-gallon shrubs at 30 inches on center in square spacing each occupy 2.5 feet by 2.5 feet, which is 6.25 square feet, so a 400 square foot bed takes 400 divided by 6.25, which is about 64 plants. Sod sold in pieces covering 10 square feet each covers 2,700 square feet in 270 pieces before waste, and a lawn 32 by 45 feet is 1,440 square feet, or 144 pieces, which becomes about 160 rolls once a typical waste allowance for cuts and edges is added. Rate-based materials are simple multiplication: seed specified at 8 pounds per 1,000 square feet on 7,500 square feet requires 60 pounds, and fertilizer at 4 pounds per 1,000 square feet on 5,000 square feet requires 20 pounds. Estimators add a percentage to a calculated concrete quantity because subgrade irregularity and spillage consume material that the geometric calculation does not see, and they add waste allowances to plant and sod counts for the same reason. A bid form ultimately lists quantities from the takeoff, such as 340 linear feet of edging and 12 hours of equipment time, priced at unit rates.
Labor, Overhead, Markup, and Margin
Direct labor cost is the crew wages plus payroll taxes plus workers compensation premium for the hours actually spent on the job, and that burdened figure, not the bare hourly wage, is what the estimate is built on. Overhead is different: office rent, general liability insurance premiums, vehicles not assigned to a job, and administrative salaries are overhead costs rather than direct job costs, and they are recovered by adding a share to every job. Labor quantities come from production rates. If an estimator uses a production rate of 250 square feet of sod installed per crew-hour, a 3,000 square foot lawn takes 3,000 divided by 250, which is 12 crew-hours. Production rates should come from the company's own historical records on completed jobs, because a company's own crews, equipment, and typical site conditions predict its costs far better than a published national average does. Markup and margin are the calculation candidates get wrong. Markup is a percentage of cost; margin is a percentage of the selling price. A job costing 10,000 dollars on which the contractor wants a 20 percent gross margin on the selling price must be priced at 10,000 divided by 0.80, which is 12,500 dollars, and adding a 20 percent markup instead would have produced 12,000 dollars and a margin of only about 16.7 percent. A contingency line in the estimate covers cost exposure from conditions that cannot be fully known at bid time, such as buried debris, unexpected rock, or a subgrade that will not compact. A lump sum bid for a defined scope puts the risk of underestimated quantities or unforeseen site conditions on the contractor, since those costs come out of profit, which is precisely why the contingency and the scope exclusions matter. A landscape maintenance agreement priced for a full year is most reliably built from a task-by-task schedule of visits with estimated hours for each season, rather than from a single monthly figure, because the work is heavily seasonal. And the practice that tells a contractor whether a completed job actually made money is comparing actual job costs to the estimate line by line, which is also how production rates get better over time. When two bidders quote the same landscape job and one is 30 percent lower, the most reasonable inference is not that one is more efficient but that the two are not pricing the same scope, materials, or quantities.
Permits, Contracts, and Licensing Law
Landscape projects trigger more permits than owners expect. Grading and retaining wall work generally require permits from the local building or public works department, and work in a public sidewalk area or right of way generally requires an encroachment permit, so a project involving grading, a retaining wall, and a new gate in a public sidewalk area should be assumed to need all three. Because thresholds for grading volume, wall height, and slope are set locally, confirm them with the jurisdiction rather than applying a remembered number. The California contract rules that apply to residential landscape work are the same ones that govern any home improvement contract. A residential landscape job being sold for 18,000 dollars requires a written home improvement contract signed before work begins, under Business and Professions Code section 7159. The down payment is limited to the lesser of 10 percent of the contract price or 1,000 dollars, so on a 30,000 dollar residential landscape contract the maximum down payment is 1,000 dollars, not 3,000, because the dollar cap is lower than the percentage. A homeowner who signs a contract at their kitchen table has a statutory right to cancel within three business days, disclosed in the agreement, and the cancellation period is longer for senior citizens; the notice of cancellation must be provided with the contract. The minor work exemption at section 7048 does not cover a 1,400 dollar planter, because the aggregate price for labor and materials exceeds the statutory threshold, which Assembly Bill 2622 raised to 1,000 dollars effective January 1, 2025; the exemption also requires that the work not need a permit, not be part of a larger project, and be performed without hiring additional workers. Advertising for landscape services must include the license number issued by the board. A contractor hiring three seasonal laborers takes on mandatory workers compensation coverage for those employees. The contractor's license bond provides limited recovery for certain parties harmed by a licensee's violations, and it is not liability insurance and not a substitute for it. Two more business practices belong here. Added scope, such as an owner asking for an additional planting bed after the contract is signed, is handled with a written change order describing the work and the price, signed before the work proceeds. And a supplier delivering plants to a job protects its right to file a mechanics lien by serving a preliminary notice on the owner and lender within the statutory time, which is why a contractor who receives such a notice should understand it as routine rather than as an accusation.
Last updated: September 2026