Wholesale Hardscapes
Corrugated Down Spout Adapter 4 in x 3.25 in x 2.5 in Flexdrain
$12.00
Corrugated Downspout Adapter – 4" x 3.25" x 2.5" Flex Drain
The Flex Drain corrugated downspout adapter is the essential connector between your home's gutter downspout and your underground drainage system. It transitions a standard rectangular downspout outlet (3.25" x 2.5") into a 4" corrugated pipe run, allowing you to route roof runoff away from foundations, patios, driveways, and hardscape installations. Without proper downspout drainage, water pools at the base of structures and undermines paver bases, retaining walls, and foundations over time.
This is one of those small fittings that makes or breaks a drainage system. Every downspout on the property should connect to an underground pipe run that discharges away from the structure — and this adapter is how it starts.
SPECIFICATIONS
Specifications
- Inlet: 3.25" x 2.5" (standard residential downspout)
- Outlet: 4" corrugated pipe connection
- Material: HDPE
- Compatibility: Connects to 4" single-wall corrugated pipe (snap or friction fit)
- Color: Black/Green (varies by stock)
- Use: Residential and commercial gutter-to-underground drainage transitions
HOW TO USE
Installation Tips
- Cut the downspout flush at the desired connection height and slide the adapter over the outlet
- Secure with a sheet metal screw or hose clamp if needed
- Connect to solid 4" corrugated pipe and run to a pop-up emitter, dry well, or daylight outlet
- Maintain minimum 1% slope on the underground run
- Keep the adapter accessible for cleanout — leaves and debris can accumulate at the transition
DETAILS
Complete Your Project
- 4" x 100' Flex Drain Corrugated Pipe (the underground run)
- Pop-Up Emitters (discharge point)
- Catch Basins (if combining multiple downspout lines)
- Pea Gravel (pipe bedding)
- Elbows and Tees (for routing around obstacles)