How Far Away From My House Should Drainage Extend? A North Carolina Homeowner’s Guide
One of the most important steps in protecting your home’s foundation is ensuring that water drains away from the structure properly. Poor grading and improper drainage are two of the most common causes of foundation settlement, moisture intrusion, mold growth, and crawl space issues. If you’ve ever wondered, “How far away from my house should drainage extend?”, the answer isn’t just a recommendation. In North Carolina, it’s a code requirement.
At Elite Foundation Services, we help homeowners understand these standards so they can prevent future foundation problems before they start. Below, we break down what the North Carolina State Building Code says about proper drainage around foundations and what that means for your home.
North Carolina’s Required Drainage Distance From the Home
The North Carolina State Building Code, which follows the ICC/IRC model building codes, has clear rules for how water must be directed away from homes. These regulations help ensure that rainwater and surface runoff don’t collect around your foundation, where they can cause costly long-term damage.
1. The Ground Must Slope Away from the Foundation
The building code states that every lot must be graded so that surface water drains away from the foundation walls.
More specifically:
The grade must fall a minimum of 6 inches within the first 10 feet of the home.
This means that from the moment the ground begins at the exterior of your home, there needs to be enough slope to ensure water flows outward, not inward.
Why this matters:
Without adequate slope, water can pool near the structure, saturating soil and leading to foundation settlement, cracks, mold, and crawl space moisture issues. Even small amounts of standing water can jeopardize long-term structural stability.
2. What If Standard Grading Isn’t Possible?
Many homes, especially those on tight lots, steep slopes, or near retaining walls, don’t have the physical space to create 6 inches of fall over 10 feet. If your property layout makes standard grading difficult, the building code requires alternative drainage solutions.
These include:
- Swales (shallow, sloped channels)
- French drains
- Underground drainage piping
- Channel drains
- Downspout extensions
- Surface drains
The goal is the same: ensure water moves away from the foundation efficiently.
At Elite Foundation Services, we regularly install engineered drainage systems for homes that cannot achieve adequate natural slope due to property constraints. Properly designed solutions help prevent water from lingering near the foundation and causing long-term structural problems.
3. Exterior Foundation Height Also Matters
Drainage requirements don’t stop at grading. The North Carolina code also specifies:
The top of the exterior foundation must sit above the elevation of the street gutter or the inlet of an approved drainage device where water ultimately discharges.
This prevents water from flowing backward toward the home or pooling against foundation walls during heavy rain.
If your foundation is too low relative to the final drainage point, water may move toward your house rather than away from it. This often leads to chronic moisture problems in crawl spaces and basements.
Why Proper Drainage Protects Your Foundation
When water consistently flows away from the home, you can prevent:
- Foundation cracking and settlement
- Crawl space moisture and mold
- Wood rot and pest intrusion
- Basement leaks
- Soil erosion
- Concrete deterioration
Water is the number-one enemy of foundations. Correct drainage is one of the simplest and most effective ways to protect your investment.
Need Help With Drainage or Foundation Issues?
If your home doesn’t have the required slope, or if you’re experiencing standing water, pooling, or moisture problems, Elite Foundation Services can help. Our team specializes in drainage solutions, crawl space encapsulation, grading, and foundation repair across the greater Durham NC area.
We can evaluate your property, measure your grading, and recommend the right system to keep your foundation dry and secure.
Contact us today to schedule a drainage assessment and protect your home from future damage.
