Hardscape Design and Construction Flashcards

What is the standard recommended slope for a patio or walkway to ensure proper drainage away from a structure?

Answer: 1 to 2 percent (1/8 to 1/4 inch per foot)

A 1 to 2 percent slope directs water away from buildings while remaining comfortable and safe for foot traffic.

Which base material is most commonly used beneath interlocking concrete pavers to provide stability?

Answer: Compacted crushed stone

Compacted crushed stone aggregate base provides a stable, well-draining foundation that prevents paver settling and shifting.

What is a 'setback' in the context of US hardscape design?

Answer: Required distance from a structure to the property line

A setback is the minimum distance a structure or paved surface must be located from property lines, as required by local zoning ordinances.

What type of retaining wall requires geogrid reinforcement for walls exceeding a certain height?

Answer: Segmental retaining wall (SRW)

Segmental retaining walls over 4 feet tall typically require geogrid reinforcement extending back into the retained soil for structural stability.

What is the purpose of a French drain in a landscape?

Answer: Redirect subsurface water away from an area

A French drain is a trench filled with gravel and a perforated pipe that collects and redirects subsurface water to a discharge point.

What is the recommended maximum riser height for exterior landscape steps to ensure safety and comfort?

Answer: 7 inches

Exterior steps should have risers no taller than 7 inches, with a common formula of 2R plus T equals 26 inches guiding comfortable step proportions.