What Are Downspout Extensions?
A downspout that terminates at the foundation wall concentrates the entire roof drainage at the most vulnerable point of the structure. APS Foundation installs surface extensions and underground piping to route downspout discharge at least 10 feet from the foundation, the minimum effective distance to prevent soil saturation at the perimeter. Surface extensions are appropriate for flat yards where water can be directed to drain away from the structure. Underground piping is appropriate where surface extension is impractical due to grade, landscaping, or hardscape. APS designs the discharge solution for each site.
The 10 foot minimum is not arbitrary. Discharge closer than that keeps the backfill zone around the foundation saturated, and in expansive Alabama clay a saturated backfill zone is a swelling one. Extensions carry the water past that zone; underground drainage carries it further, to daylight, a catch basin, or a pop up emitter at the yard edge.
APS treats downspout discharge as part of the foundation system. On many waterproofing and drainage jobs the highest value fix is the simplest one: getting roof water those extra feet away from the house. Our crews route extensions under lawns and beds so nothing shows on the surface, size the pipe to the roof area feeding it, and slope every run so it drains completely between storms.
Assessments are free, recommendations arrive in writing, and installed drainage carries the manufacturer warranty plus our in house performance warranty.
How APS Approaches Downspout Extensions
- 1
Free On-Site Assessment
A trained APS technician visits your property, documents the problem, and identifies the root cause before recommending any repair.
- 2
Written Estimate
You receive a clear scope of work and cost with no obligation. We explain the method chosen and why, in plain language.
- 3
Repair and Transferable Warranty
Our trained crews complete the repair using professional equipment. All APS repairs carry a warranty that transfers to future owners.
Frequently Asked Questions
How far from the foundation should downspouts discharge?
A minimum of 10 feet is the standard recommendation. On flat lots with clay soil, further is better. APS designs the extension to discharge to an area of positive drainage away from the structure.