Ground type factors into your cost because it makes a difference in how quickly a hole can be dug or how difficult it will be to remove an existing concrete plug. The ground in central Texas can range from solid rock to a loose, rich soil. Generally it falls somewhere in between.
Knowing what type of soil conditions we are likely to encounter as well as where we are likely to encounter them helps us to determine what method of digging will be required and how long it will take. It can easily take one man hour just to remove an existing post and concrete base, even when using a jackhammer. We have seen posts with only three (3) inches of wood burried in the ground withstand over three thousand (3,000) pounds of lifting force and still not come out of the ground.
The soil type also determines how deep and how wide a post hole needs to be in order to properly support a fence. Posts in solid rock don't require as much depth or width as a post buried in loose or clay rich soil. The bigger the hole, the more time it will take to dig it and the more concrete it will take to fill it back up again. More time, more material, more cost.
