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Exterior

Install Gutter Downspout Extensions

MODERATE30 minExterior

Why It Matters

Water dumped next to the foundation is the primary cause of basement leaks and foundation settling in most homes.

Quick Guide

  1. 1

    Gather your tools and materials

    You'll need: Screwdriver. Materials required: Downspout extensions or underground drain pipes.

  2. 2

    Perform the install gutter downspout extensions

    Attach extensions or splash blocks to downspouts to direct water at least 6 feet from the foundation.

  3. 3

    Verify and clean up

    Check that the work was completed correctly and clean up your workspace.

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Tools & Materials

Tools

  • Screwdriver

Materials

  • Downspout extensions or underground drain pipes

Community Tips

TipKasa Team

Downspout extensions must discharge water at least 4-6 feet from the foundation to prevent basement flooding and soil erosion; rigid extensions like Ameristar Aluminum Downspout Extensions ($12-18) are superior to flexible alternatives in high-wind areas because they maintain consistent slope and resist UV degradation over 10+ years.

WarningKasa Team

Underground drain pipes require a slight 1-2% downward slope toward a dry well or storm drain—failure to achieve this slope causes standing water that freezes in winter and creates ice dams, even with premium options like DuraChannel Underground Drainage Systems ($25-40 per 10-foot section).

Cost InfoKasa Team

Installing buried downspout extensions costs significantly less upfront than foundation repairs from water damage; a complete extension system with straps and connectors typically runs $30-60 per downspout, whereas basement waterproofing remediation averages $3,000-8,000 and makes this preventative investment essential for homes in wet climates. ---