Prevention
A Foundation Watering Schedule for North Texas Clay
The cheapest foundation maintenance there is — about sixty dollars of soaker hose and a timer — and most people either skip it or do it wrong.
The principle: steady, not wet
Blackland clay swells when it takes on water and shrinks when it gives it up. Your foundation doesn’t care whether the soil is damp or dry in absolute terms. It cares whether the moisture content is changing, and whether it’s changing unevenly around the perimeter.
So the goal isn’t to soak the ground. It’s to hold moisture roughly constant year-round, on all four sides, so the clay never gets the chance to shrink away from one section of slab while another stays supported.
Which means watering is only half the job. The other half is drainage — keeping excess water from pooling against the same foundation you’re carefully keeping damp. Both, or neither works.
Setting it up
Placement. Run soaker hose in a loop around the house, roughly twelve to eighteen inches out from the slab edge. Not touching the foundation — water applied at the edge runs down the face and does nothing for the soil that matters, which is the soil supporting the perimeter beam a foot or two out. Not three feet out either; at that distance you’re watering the lawn.
Coverage. All four sides, including the side you never think about. Partial coverage creates exactly the differential you’re trying to prevent — a house watered on three sides is arguably worse off than one watered on none.
Hardware. Soaker hose, a hose-end timer, and a splitter if you need to run more than one zone. Bury the hose under an inch of mulch to slow evaporation and keep the UV off it. Total cost is usually under $100 for an average house.
Don’t use sprinklers for this. Spray heads throw water at the brick, wet the wrong zone, and lose most of it to evaporation. Soaker or drip only.
Month by month
| Period | Frequency | Run time |
|---|---|---|
| December – February | Rarely — only in a dry, warm stretch | 20 min |
| March – April | Usually off; spring rain does the work | as needed |
| May | Every 2–3 days once rain tapers | 20–30 min |
| June | Every other day | 25–30 min |
| July – August | Daily | 25–35 min |
| September | Every other day | 25–30 min |
| October – November | Twice weekly, tapering off | 20 min |
Starting points, not gospel. Shaded north sides need less than sun-exposed south and west sides. Adjust by what the soil tells you, not by the calendar.
Turn it off after meaningful rain and leave it off until the soil dries back. An inch of rain buys you several days.
How to tell if you’ve got it right
Push a long screwdriver into the soil about a foot from the foundation. It should go in with steady moderate pressure and come out with damp soil clinging to it.
- Can’t push it in, soil is like concrete, visible shrinkage gaps → too dry, water more
- Slides in with no resistance, soil is muddy, water stands after a cycle → too wet, back off
- Firm but yielding, soil damp not saturated → correct
Check a few points around the house, not just one. The differences between sides are what you’re managing.
The gap you’ll see in August, and what to do about it
Every McKinney summer, soil pulls back from the slab edge and leaves a visible gap. People find this alarming and it usually isn’t — it’s normal shrinkage and it closes when the rain returns.
What you should not do is pour water into the gap. That sends it straight down along the foundation face, saturating deep soil at the edge while the soil a foot out stays dry, which is a worse moisture profile than what you started with. Water at the soaker line and let it move laterally.
If the gap is wider than an inch or two, or doesn’t close after a wet spell, that’s worth a look.
Common mistakes
- All or nothing. Soaking heavily once a week is worse than a short cycle daily. Big swings are the whole problem.
- Watering only the visible side. The back and the side yard nobody walks through count too.
- Hose against the brick. Twelve to eighteen inches out.
- Overwatering a bed against the house. Beds already hold moisture; adding a soaker on top of bed irrigation creates a wet zone next to a dry one.
- Forgetting the tree. A large oak nearby will out-compete your soaker hose without breaking a sweat. That needs a root barrier, not more water.
Watering restrictions
McKinney is served by the North Texas Municipal Water District, and during drought stages the city implements outdoor watering restrictions that limit which days you can irrigate. Foundation watering with a soaker hose or drip is typically treated separately from sprinkler irrigation, but the rules change by stage and by year. Check the City of McKinney’s current watering stage before you set a schedule rather than assuming last year’s rules still apply.