EXTERIOR
How to Price a French Drain Job
How to price a French drain: length, depth, pipe, gravel, fabric and soil conditions.
French drain pricing lives in the cubic yards, not the linear feet. The pipe is cheap; the gravel and the labor to move the dirt are the real cost.
THE SHORT ANSWER
How do you price a French drain?
Measure length and depth, price perforated pipe, gravel by cubic yard and filter fabric, then factor soil (clay +15%, rock +45%) and access. A 60 ft drain runs $1,500-$3,500.
Measure length and depth
Measure the drain line and decide depth — typically 1.5-2 ft for a foundation drain, deeper for clay. The volume of gravel is length × depth × width, and that volume drives the price.
Price pipe, gravel and fabric
4 in perforated pipe runs $1.50-$2.50/ft; 6 in runs more. Clean gravel is $40-$70 per cubic yard delivered, and filter fabric keeps the gravel from clogging.
Factor soil and access
Clay adds 15%, rocky soil adds 45% to labor. Tight access means hand-digging or a smaller machine, both slower. Disposal of excavated soil is a real line item.
Check the total
Use the French Drain Cost Calculator and stay within 10% before markup. A 60 ft drain at 2 ft deep runs $1,500-$3,500.