RICHARDSON

Richardson filled in through the fifties, sixties and seventies, which gives it two things that combine badly on Blackland clay: slabs poured to older standards and trees that have had sixty years to grow.

A mature oak draws a remarkable volume of water out of the ground on a hot Texas afternoon, and the corner of the house nearest the biggest one dries out first and drops.

The upside is that six decades of wet and dry cycles means the ground here has largely found its equilibrium, so movement in an older Richardson home tends to be slower and more predictable than in a new build.

What the ground under Richardson is actually doing

More than a quarter of Richardson sits on Austin soil, with Eddy — a thin soil directly over chalk, extensibility just 1.5 — under a further 15%. Both are far calmer than the Blackland reputation of this region suggests.

Then there is Houston Black beneath about an eighth of the city, at 13.7. Richardson’s real foundation story is that boundary: a house near where shallow chalk gives way to deep expansive clay can have one end on ground that barely moves and the other on ground that moves a great deal. That is a differential-movement problem, and it is the kind that cracks brick.