Expansive clay around San Angelo
Slaughter 土，黏土 31%，lep=4.5（中度脹縮）.
Slaughter 土，黏土 31%，lep=4.5（中度脹縮）
Soil sampled near San Angelo runs 31 percent clay with a linear extensibility of 4.5, which is the standard measure of how much that ground changes volume with moisture.
Why this matters for a footing
A footing is designed for a soil that stays roughly the same size. When the ground beneath one part of the house changes volume and the ground beneath another part does not, the house is asked to bridge the difference, and concrete is not good at that.
San Angelo records about 18 days a year where the temperature crosses freezing between night and day, and each of those cycles works existing cracks a little wider.
What you can do without spending much
- Get roof water away from the wall - extensions on downspouts are the cheapest intervention there is
- Keep the soil moisture around the perimeter even rather than swinging wet to bone dry
- Watch tree roots close to the footing, which draw moisture out of one side only
- Mark and date crack ends, then photograph them each season
The median home in San Angelo was built in 1978, which sets what the footing is likely to be and how deep it sits.
Prices in nearby cities
Abilene · Allen · Amarillo · Baytown · Beaumont · Bedford · Carrollton · College Station · Corpus Christi · Denton · Georgetown · Killeen