The Texas Section of the American Society of Civil Engineers recommends a minimum slope of 5 percent away from the foundation for the first 5 feet all around, which is 6 inches of fall in 10 feet. Water that pools at a wall feeds the soil that moves the slab. Here is what the guidelines say about grading, gutters, downspouts, trees and watering, and what we check on a Keller house.
The Short Answer
Move the water away from the house and keep the soil moisture even. The ASCE guidelines call for the grade to fall away from the foundation, downspouts that discharge well past the edge and no perforated pipe on downspouts. Foundation Repair Keller TX checks all of it on every inspection, because a repair over a drainage fault fails again.
What the Guidelines Say
| Item | ASCE Texas Section guideline |
|---|---|
| Surface grade | A minimum slope of 5 percent (6 inches in 10 feet) away from the foundation, for the first 5 feet all around (Section 7.3.5.1). |
| Downspouts | Extend well past the edge of the foundation, into well-drained areas (Section 7.3.4). |
| Solid drain pipe | Downspouts may connect to solid pipe drainage systems if the pipe is large enough for the roof water load (Section 7.3.5.3). |
| Perforated pipe | Downspouts should not connect to perforated pipe subsurface drainage systems (Section 7.3.5.4). |
| Subsurface drains | Appropriate to control subsurface water (Section 7.3.5.4). |
| Soil moisture | Maintaining near uniform soil moisture on all sides of the foundation may be beneficial, and caution is advised against excessive watering (Section 7.3.1). |
| Trees and shrubs | Trees or large shrubs near a foundation may cause soil shrinkage under it. After tree removal a waiting period may be recommended for soil heave. Root barriers are generally not as effective as tree removal (Sections 7.3.2 and 7.3.3). |
Why Water Matters in Keller
The Dallas/Fort Worth weather station records about 37 inches of precipitation a year, and the roof of a house sheds that water to the edge in a few places. A downspout that empties beside the wall puts a stream of water into the soil next to the slab. The ASCE guidelines state that Texas has large areas with clayey soils that shrink and swell with changes in soil moisture, and the USDA soil survey for Tarrant County maps clay soils in patches around Keller. Why Keller soil moves foundations
The weather station also records about 20 days a year at or above 100°F, so the soil beside a house dries in summer. A wet side and a dry side tilt a foundation.
What We Check on a Keller House
- The grade. We check that the ground falls away from the wall, and flag any spot where it slopes toward the house or holds water.
- The gutters. We look for full, sagging or leaking gutters that spill at the wall.
- The downspouts. We check where each one discharges, how far from the foundation, and whether any connect to perforated pipe.
- The beds. We look at planting beds against the slab that hold water.
- The trees. We check large trees and shrubs near the foundation.
- The watering. We ask how and where the yard is watered.
What We Do About It
We regrade low spots, extend or redirect downspouts and correct a bed that traps water. A repair plan names each drainage fix, so the work you pay for addresses the cause. Foundation leak repair
Frequently Asked Questions
How should the ground slope around a foundation?
The ASCE guidelines recommend a minimum slope of 5 percent away from the foundation for the first 5 feet all around, which is 6 inches of fall in 10 feet, or about 3 inches across the first 5 feet. We check the grade with a level and mark the spots that slope toward the house.
How far should a downspout extend from the foundation?
Well past the edge of the foundation and into a well-drained area, according to the ASCE guidelines. We judge the distance by where the water lands and which way the ground slopes. We quote an extension where the water drops too close.
Can I connect a downspout to a buried drain pipe?
To solid pipe, if the pipe is large enough for the roof water load. The ASCE guidelines state that downspouts should not connect to perforated pipe subsurface drainage systems. We check what sits at the end of each downspout. Foundation leak repair
Should I water my foundation in summer?
The ASCE guidelines state that maintaining near uniform soil moisture around the foundation may be beneficial, and they advise caution against excessive watering. Even moisture on all sides is the goal, and a flooded strip is not. We look at how a yard is watered when we inspect a house that shows movement.
Do trees cause foundation problems?
They can. The ASCE guidelines state that trees or large shrubs near a foundation may cause soil shrinkage under it, and that root barriers are generally not as effective as tree removal. After a tree comes out, a waiting period may be needed for soil heave. We note trees on the inspection. Signs of foundation problems in Keller
