Landscape Construction, Hardscape, and Grading
What this domain tests
This domain tests drainage and grading tolerances, base and subgrade preparation for pavers and concrete, retaining wall and pool barrier requirements, and the erosion and sediment controls required on a Florida construction site.
Grading and drainage
- The Florida Building Code requires finish grade to fall about 6 inches within the first 10 feet of a foundation, and site grades must drain positively to a swale, street, or easement with no ponding.
- Establish final grade before setting pavers, walls, or beds. Grading without checking door thresholds and slab elevations is the classic error.
- Protect trees: barricade the critical root zone at the dripline, avoid fill or cut of more than a few inches over roots, and keep equipment off the root zone.
Hardscape
- Pavers: compacted aggregate base of 4 inches for pedestrian and 6-8 inches for vehicular use, 1 inch of bedding sand, edge restraint, geotextile over soft soils, and 1.5-2% slope.
- Concrete: 4 inches thick, 2,500-3,000 psi, control joints at 8-10 ft or two to three times slab thickness, isolation joints at structures.
- Segmental walls need a 6-inch compacted leveling pad, gravel drainage and weep holes behind the wall, geogrid per design, and typically engineering and permits above about 4 ft.
- Pool barriers must be at least 4 ft high, free of climbable features, with self-closing and self-latching gates.
Erosion control
- Disturbing an acre or more triggers FDEP's NPDES Construction Generic Permit, a SWPPP, inspections every 7 days and within 24 hours of a 0.5-inch rain, silt fence, inlet protection, and a stabilized construction entrance.
Worked example
A 24 ft by 18 ft patio is 432 sq ft and needs a 6-inch compacted base. Volume in place = 432 x 0.5 = 216 cu ft = 8 cu yd. Aggregate loses roughly 20-25% of its loose volume under compaction, so order 8 x 1.25 = 10 cu yd. The 1-inch bedding course is 432 / 12 = 36 cu ft, about 1.3 cu yd of sand. Skipping the compaction factor is how crews run short at the end of the day.
Traps
- Grading to the plan without checking thresholds, slabs, and outfall elevations.
- Omitting edge restraint so pavers creep and joints open.
- Placing base in one deep lift instead of compacting in lifts.
- Working without permits for walls, docks, or tree removal; mangroves carry separate state rules.
- Installing silt fence and never maintaining it after the first storm.