A Systems Approach to Landscape Construction

James Ruben published this post on Mar 24, 2021. It was updated on Oct 11, 2022.

Core idea

A systems approach to landscape construction uses unit pricing and prefabricated modular components instead of broad square-foot multipliers. The goal is more accurate costing for materials and labor.

Why it matters

• Cocktail-napkin estimates can overstate costs.
• Underestimating costs creates project problems.
• Unit pricing gives a higher level of cost analysis.
• Prefabrication can reduce on-site staging and cleanup.

Example: mortared stone staircase

The article breaks a stone staircase into individual tasks rather than pricing it as a single area.

• Excavation
• Grading
• Compaction of drain rock
• Choosing one stone at a time from a pile
• Trimming
• Setting the stone on a scree of mortar
• Grouting the joints
• Acid etching
• Clean-up
• Hauling away overage materials and equipment
• Mitigating damage to flanking plant materials

Prefabricated modular step system

The example system uses a prefabricated modular step with a U-shape metal stair body and an infilled tread.

Benefits

• Fabrication is outsourced.
• Grading is limited to leveling the embankment.
• Stair bodies overlap and are staked into the ground.
• A one-man crew can install ten steps a day using only hand tools.
• Different tread infill materials can be used.
• Installing the stair body does not disturb flanking plant materials.

Possible tread infills

• Stone flags
• Brick
• Pavers
• Compacted decomposed granite
• Rammed earth

Costing advantages

With this approach, the builder knows up front the material cost per stair body, the material cost of the tread infill, and the standardized labor time per stair body for installation and infill.

Construction workflow

Feathering prefabrication into construction can make installations cleaner and more cost-effective. While the metal shop produces the stair bodies, the crew can work on other parts of the project and schedule skilled labor more strategically.

Manual mentioned

The post says this Fabrication-to-Installation approach is especially effective for landscape feature development. It references a first 32-page how-to manual on Hillside Staircase, described as a step-by-step guide for metal shop fabrication and installation.