Subsidence, efflorescence and thermal expansion

An inspection from today raised a few external examples of what we look out for during a snagging survey.
As a quick physics explaination why subsidence occurs, for a structure to be stable, the force (load) bearing down must be opposed by an equal force pushing upwards. When both upward and downward forces are of the same they are said to be in equilibrium. When the downward force is greater than the upward force, according to the stability as explained regarding equilibrium, the structure will subside,
The most common issue effecting the natural balance occuring around foundations is the weather, and specifically in winter a shrinkable soil generally increases in volume, whereas in summer due to the lack of rainfall, it is reduced and evaporation through the increase in temperature causes a clay soil to shrink. In winter as rainfall increases and evaporation decreases; the soil will swell.
As well as clay soils being the catylist, a common cause making this process worse in new build houses is adjacent trees / vegetation which alter the volume of a clay soil's moisture level.
Subsidence typically can be identified in a staircase (stepped) appearance and differs to heave in the way the crack increases in width (as it goes up). Coversly if you see the cracks get wider the lower it goes, it is heave which is upward movement.

Efflorescence occurs due to the salt mixture in the brick which in excess can be damaging over time and should be scrubbed with a wire brush to make good.
The last example of interest from todays new build snagging survey  was thermal expansion. The wall span ideally required a movement joint to prevent the expansion and contraction of clay bricks and render to crack. Despite being patched previously by the builder there was a clear crack down the wall due to thermal expansion over the past year.