How to Price a French Drain Installation | Reddit & LinkedIn

A French drain quote has three buckets: materials, excavation labor, and spoil handling. Materials are gravel, perforated pipe, and filter fabric, which are relatively cheap. The real cost is moving dirt: digging the trench to depth and hauling the spoil away.

The cost driver customers never see coming is the outlet. A French drain is gravity fed, so the water has to run downhill to daylight, a dry well, or a storm connection. If the yard is flat or the outlet is far away, you may need a longer run, a deeper trench, or a pump, and that changes the price materially. Confirm the outlet before you put a number on paper.

Depth is the quiet budget driver. A shallow curtain drain is fast. A deep footing drain along a foundation means a lot more spoil, slower digging, and sometimes shoring for safety. Every extra foot of depth multiplies labor and haul-off, not just adds to it.

Measure the required depth against what the water problem actually needs, not a default. Over-digging wastes money and under-digging leaves the customer with a drain that does not solve the problem. Price the depth you need, document it, and explain to the customer why a basement-wall drain costs more than a surface drain in the lawn.

Three things routinely blow up a drainage estimate: rock, roots, and utilities. Hitting ledge rock can stop a machine cold and force hand work or breaking. Mature tree roots slow a trench and may require rerouting. And a buried gas, water, or electric line that was not located is both a safety hazard and a schedule killer.

Always call for utility locates before you dig, and probe for rock during the walkthrough. Then carry a contingency, often 10% or more on drainage work, because subsurface conditions are the one thing you cannot fully see when you quote. A documented contingency is more honest than a surprise change order.

Markup on excavation and drainage work commonly runs 20% to 30% on direct cost for a small contractor, reflecting the equipment, the risk, and the unknowns underground. Your own overhead and target profit set the real number. Remember markup is not margin: a 25% markup is a 20% margin.

Drainage carries more risk than most landscape work because so much is hidden until you dig. Price that risk honestly rather than shaving the bid to win, because a drain that fails or a dig that hits rock will eat any thin margin and then some. Build the contingency in and present it plainly.

The fastest path from site visit to signed quote is to draft against your own templates. ContractShield lets you snap photos of the water problem, the grade, and the outlet, say or type the scope, and get an AI draft of gravel, pipe, fabric, and excavation labor in about 25 minutes total. You approve each line, and every line shows where its price came from, so the numbers stay yours.

Once the customer accepts online, milestone payments are built in, with automatic reminders and collections if a balance goes past due. The same tool that priced the job also gets you paid, and the documented scope protects you if the customer questions the outlet later.