How to Redirect Downspout Water Away from Your Foundation

Water is the single greatest threat to your home's structural integrity. When downspouts dump roof runoff directly against your foundation walls, the surrounding soil becomes oversaturated, leading to hydrostatic pressure, basement leaks, and potential cracks in the concrete footer. Redirecting this water is the single most effective way to dry out a basement or crawlspace. Done well, this project is invisible and permanent. You are essentially creating a gravity-fed highway that carries water past the danger zone and into a safe drainage area. Whether you use simple above-ground extensions or bury hard-piped lines, the goal is always the same: ensure the water flows away from the structure and reaches a point where it can safely disperse without seeping back toward your foundation.

  1. Spot the Water Pooling. Walk your perimeter during a heavy rain to see exactly where water pools. Ensure the ground slopes away from your foundation at a minimum grade of one inch per foot for the first six feet.
  2. Choose Rigid Over Flexible. Decide between flexible plastic extensions for quick fixes or solid PVC pipe for a permanent, buried solution. If you choose to bury the pipe, stick to solid PVC rather than corrugated flexible pipe to prevent clogs and root intrusion.
  3. Dig the Trench Smart. Remove grass and mulch along the intended path of the downspout extension. If burying, dig a trench at least 6 inches deep, maintaining a steady downward slope away from the house.
  4. Seal the Connection Point. Secure the universal downspout adapter to the existing gutter spout using sheet metal screws. Use exterior-grade silicone caulk to seal the connection point and prevent leaks at the joint.
  5. Cement Sections in Place. Connect your PVC sections using appropriate couplings and primer/cement. Ensure the pipe rests firmly in the trench and maintains a consistent slope toward the exit point.
  6. Tamp Down & Resod. Cover the pipe with soil, tamping it down firmly as you go to prevent future settling. Replace your sod or mulch over the trench to restore your landscaping appearance.