Foundation drainage and moisture control
In shrink-swell clay, controlling water around the house is as important as any pier. Here's what helps and why.
Expansive clay moves when its moisture changes. The aim around a foundation isn't to make the soil bone-dry or soaking wet; it's to keep it as even as possible, all the way around the house, all year. Water pouring off a roof at one corner while the other side bakes in the sun is a recipe for uneven movement.
Signs your drainage is part of the problem
- Downspouts dumping right at the foundation
- Soil sloping toward the house, or flowerbeds edged so they hold water
- Puddles along the foundation after storms
- Wide cracks in the soil next to the slab during dry spells
- Water in the crawl space of a pier-and-beam house
Common fixes
- Gutters and downspouts that carry roof water well away from the foundation, often through buried lines to daylight
- Regrading so soil slopes away from the house on all sides
- Surface drains and French drains to move water out of low spots
- Crawl space drainage for pier-and-beam houses
- Steady watering during long dry spells, applied evenly around the foundation rather than flooding one area
What about trees?
Large trees close to the house pull moisture out of the clay, especially in summer, and can cause one side of a house to drop. Root barriers or tree removal are sometimes recommended. Talk to an arborist before cutting a large tree, because removing one can also change how the soil behaves.
What about plumbing leaks?
The Oklahoma Geological Survey lists sewer leakage, along with rain and lawn watering, as a source of water that can make expansive soils swell under foundations. A sudden rise in the water bill, a hot spot on a slab floor, or the sound of running water when everything is off are reasons to call a plumber.
City drainage questions
If water from the street or a public drainage channel is reaching your property, the City of Lawton's Stormwater Management Division can be reached at 580-581-3478.
The contractor prices the job after measuring the house and working out why it's moving. We don't quote prices, and a figure given over the phone before anyone has taken floor elevations is a guess at best.
Where we connect you with help
Common questions
Should I water my foundation?
In long dry spells, even watering around the foundation can help limit shrinkage in clay. The goal is steady moisture, not soaking one side. Ask your contractor how they'd approach it for your house.
Is drainage work done by foundation companies?
Many foundation contractors do gutters, downspout lines, grading and drains, or work with someone who does. Ask whether it's part of the bid.
Related services
- Slab foundation repair
- Pier-and-beam foundation repair
- Foundation piers (steel, helical, concrete)
- Foundation inspections and crack repair
More background: Lawton foundation repair guide.
Doors sticking, new cracks in the brick, or a floor that slopes?
Call and a local foundation contractor will come measure it and tell you what they find.