EXTERIOR
How to Estimate a Downspout Extension
Contractor method to estimate a downspout extension by length, material, elbows, bury and labor with clear materials and labor lines.
A downspout extension moves water away from the foundation, and the price is mostly the pipe run, the elbows and whether you bury the line. This guide covers measuring the run, choosing the material, and pricing the surface or buried options.
THE SHORT ANSWER
How to Estimate a Downspout Extension
15 ft of vinyl extension with one elbow, not buried, and 3 labor hours at $60 totals about $210.50.
Measure the run to daylight
Price by the length you need to carry water away from the foundation. Measure from the downspout outlet to where the water can drain safely.
- Run length
- Material
- Elbows
- Bury vs surface
PVC vs flexible
Rigid PVC is durable and looks clean but takes fittings; flexible extensions are quick and cheap but less permanent.
Burying the line is a bigger job
A buried downspout needs a trench, a slope and a pop-up emitter. It costs more but keeps the yard clear of surface pipe.
Compare downspout quotes
Ask for the run, fittings and any burial as separate lines. Confirm the slope so water does not puddle.