What should a scope of work for a drainage project include?

A drainage scope of work should include existing conditions documentation, system design with pipe sizes and slopes, detailed materials specifications, construction methods, site restoration plans, performance standards, change order procedures, payment milestones, warranty terms, and a clear list of exclusions. A site plan showing the system layout should also be attached.

How do I protect myself as a contractor when writing a drainage contract?

Protect yourself by explicitly documenting assumptions about subsurface conditions, defining measurable performance standards instead of guaranteeing results, including a detailed change order process with pre-set rates, and listing all work exclusions. Always photograph existing conditions before starting and require written homeowner approval for any scope changes.

What is a reasonable payment schedule for residential drainage work?

A typical payment schedule is 25-35% deposit at contract signing, 30-40% upon completion of pipe installation before backfill, and the remaining 25-35% at project completion. This milestone-based approach protects both parties and creates natural inspection points. Avoid collecting more than 50% before starting work.

How specific should materials be listed in a drainage scope of work?

Materials should be specified by type, size, and applicable standard. For example, instead of writing 'drainage pipe,' specify '4-inch perforated corrugated HDPE pipe conforming to ASTM F405 with filter sock.' This level of detail prevents substitution disputes and ensures the homeowner knows exactly what they're paying for.

Should a drainage contract include a warranty?

Yes. A typical drainage warranty covers materials and workmanship for 1-2 years and should specify what is and isn't covered. Common exclusions include root intrusion, third-party damage, homeowner modifications, and extreme weather events. Require warranty claims to be submitted in writing within a defined timeframe.

How do I handle unexpected conditions during a drainage project?

Include a change order protocol in your scope of work that defines triggering conditions such as buried debris, unexpected soil types, or unmarked utilities. The process should require written notification to the homeowner, a written cost estimate for additional work, and written approval before proceeding. Including pre-set time-and-materials rates in the original contract builds trust.

Scope of Work for Drainage Projects: Contractor's Guide

Learn how to write a bulletproof scope of work for drainage contracts. Covers grading, materials, testing, and change orders to protect you and your clients.

By Low Point Labs

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