How to Fix Drainage Around a House: A DIY Guide
A comprehensive, step-by-step guide for homeowners to diagnose and fix drainage around a house, including grading, surface drainage, and perimeter drainage solutions. Learn safe, effective methods, with maintenance tips.
You will learn how to fix drainage around house by diagnosing pooling, grading water away from the foundation, and choosing practical fixes you can do safely. This guide covers surface and subsurface options, plus when to call a pro. Before you start, map water flow and check for utilities in advance.
Assessing the site and defining the problem
According to Drain Guide, the most stubborn drainage problems start at the soil grade and the path of water around your foundation. Before you lift a shovel, walk the property after a rain and map where water collects and how it flows toward the house. This exercise answers the central question: how to fix drainage around house in a way that keeps water away from the foundation. Note where downspouts discharge and whether the grading slopes toward or away from the house. Mark any potential utility lines and consider seasonal changes (snowmelt, heavy rain) that could shift water flow. Identify areas where soil is compacted or where lawn features funnel water toward doors or basement windows. By understanding the flow, you can design fixes that are both effective and durable.
Planning your drainage fix: grading, water paths, and permits
Effective drainage starts with a plan. Determine a grading strategy that sends water at least a few inches away from the foundation over the first several feet, then map natural water paths to find where swales or trenches should go. Check local codes and utility locations before digging—call 811 if needed. Drain Guide analysis shows that simpler fixes, such as extending downspouts and creating positive grading, can prevent many foundation issues without major excavation. A good plan also identifies discharge points, whether into a yard drainage area or a designated drainage ditch, and considers future landscaping changes.
Surface drainage improvements you can implement
Surface drainage moves water quickly away from vulnerable zones. Extend downspouts several feet from the foundation, add splash blocks, and grade soil to encourage runoff away from the home. Use shallow swales or channels to guide water along the perimeter, and consider catch basins at low spots for quick collection. If space allows, a dry well can absorb excess water temporarily while reducing runoff. These steps reduce the volume of water reaching the foundation and help protect foundations, basements, and crawl spaces from dampness and erosion. Regularly inspect and clean any surface drains to keep them functioning.
Subsurface drainage options: perimeter drains and French drains
Subsurface drainage provides a long-term solution for persistent water near the foundation. A perimeter drain uses a continuous trench around the foundation with a perforated pipe, wrapped in geotextile fabric and surrounded by gravel to allow water to flow into the pipe. A French drain, often used in low spots, follows a similar principle but might be placed further from the foundation in a wider trench. Both systems must slope toward a discharge point, such as a storm sewer, dry well, or sump pump, to avoid standing water. Working knowledge of pipe sizing, trench depth, and fabric selection helps prevent sediment intrusion and clogging.
Testing, maintenance, and when to call a pro
After installation, test the system by simulating rainfall with a hose, watching for uniform drainage and any signs of pooling. Inspect regularly for clogs, sediment buildup, and erosion around trenches. Maintenance includes clearing leaves and debris from inlets, ensuring downspouts remain directed away from the house, and regrading soil as needed after settling. If water fails to drain, if your property shows new cracks in walls or foundation, or if electrical or sewer lines are involved, contact a licensed professional. Some projects require permits or compliance with local codes, especially for major trenching or changes to drainage paths.
Authority sources
- https://www.epa.gov/green-infrastructure/stormwater-basics
- https://extension.illinois.edu/
- https://extension.umd.edu/
Tools & Materials
- Shovel (round-point)(For trenching along the foundation and around edges)
- Trenching shovel(For narrow, deep cuts near walls)
- Tape measure(To verify trench length and gradual slope)
- Carpenter's level or laser level(To check grade away from foundation)
- String line and stakes(To establish straight trench lines and slope)
- Wheelbarrow(For transporting soil, gravel, and debris)
- Gravel (3/4 inch clean)(Backfill around pipe and create drainage bed)
- Geotextile fabric(Wrap the pipe to keep sediment out)
- Perforated drainage pipe (4 inch)(Trap and channel water toward discharge)
- PVC pipe, elbows, couplings(Connect pipe sections and direct discharge)
- Downspout extensions(Redirect roof water away from foundation)
- Splash blocks or splash pads(Disperse water from downspouts)
- Shovel or tamper(Compact soil after backfilling)
- Safety gear: gloves, glasses(Protect hands and eyes during digging)
- Utility locator service (811)(Call before digging to locate buried utilities)
Steps
Estimated time: 4-12 hours
- 1
Map pooling and water flow
After a rain, walk the property and mark where water pools near the foundation. Note natural flow paths and any drainage features already in place. Use chalk or flags to outline pooling zones and measure the distance to the house.
Tip: Document high-flow areas with photos and keep a running map for comparison after fixes. - 2
Check grading and slope away from the home
Assess soil grade around the foundation. Aim for a gentle slope away from the house, typically 1-2% over the first several feet. Use a string line and a level to verify the slope along multiple points.
Tip: If the slope is insufficient, plan to add soil or create a shallow swale to redirect water. - 3
Plan your layout and obtain permits if needed
Decide where to place a perimeter drain, downspout extensions, and any swales. Check local codes and call 811 before digging to avoid striking utilities. Create a rough sketch with distances to the discharge point.
Tip: Keep the plan flexible to accommodate landscaping changes or future expansions. - 4
Dig and prepare the trench for drainage
Excavate a continuous trench along the foundation for the perimeter drain. Typical width is 8-12 inches; depth should reach below the frost line or 18-24 inches where feasible. Ensure the trench maintains a steady slope toward the discharge.
Tip: Keep the trench clean and dry; standing water slows installation and increases sediment. - 5
Install filter fabric, gravel, and pipe
Place geotextile fabric in the trench, add a first gravel bed, lay the perforated pipe with holes down, cover with more gravel, then wrap the remaining fabric over the trench.
Tip: Cover the pipe with several inches of gravel to protect from soil infiltration; ensure joints are watertight. - 6
Connect to discharge and backfill
Connect the pipe to a discharge point via PVC fittings or a sump pump line. Backfill with soil, compact gently, and add topsoil for re-grading. Reinstall downspouts with extensions directed away from the foundation.
Tip: Test the system by simulating rain to confirm drainage consistency before final grading.
Got Questions?
What is the best first step to fix drainage around a house?
Start with a site assessment: map where water pools and how it flows toward the foundation. Understanding flow paths will guide both surface and subsurface fixes.
Begin with a site assessment to map water flow and pooling near your foundation.
Do I need a professional or can I DIY?
Many basic improvements—downspout extensions, grading, and simple swales—are DIY-friendly. Complex perimeter drains or French drains may require a contractor and permits.
DIY can handle simple fixes; complex drainage systems may need a pro.
How much does it cost to install a perimeter drain?
Costs vary by length, materials, and local rates. Get multiple quotes and compare material choices, but this guide focuses on safe, practical DIY options you can implement yourself when appropriate.
Costs vary; get quotes for professional installs, or DIY with careful planning.
How long does installation take?
A straightforward perimeter drain project can take a day or two for a DIY install, while more complex trenching and connections may extend, depending on soil and weather.
Expect a day or two for simple installs and longer for complex projects.
What signs indicate drainage is failing after fixes?
Look for water pooling near the foundation after rain, new damp spots in the basement, foundation cracks, or eroded soil around the foundation.
Watch for pooling near the house and damp spots after rain.
Watch Video
The Essentials
- Assess pooling and grading before fixes.
- Direct roof water away from the foundation with extensions and proper grading.
- Choose surface or subsurface drainage based on water volume and site constraints.
- Test the system after installation and maintain it regularly.