Jumping off from Why does the plaster crack beneath the window sill? question, and the calm/collected answers therein.
When (if ever) should I be concerned about the absolute number of cracks around doors and windows, their appearance and growth. I have cracks radiating from the tops of many of my doors and windows, and they have been becoming more noticeable AND numerous over the past couple of years.
Again referencing the above question, when/how would I know if I really do have a structural issue, instead of normal settling? And if I do have such an issue, what kind of expert do I need (what keyword to search for)?
For reference my house is drywall with a complete skim coat of plaster (odd, yeah I know), not merely taped/mudded. The soil when I dig down I would describe as clay-ish, but I am no soil engineer!
Best Answer
The important thing about cracks is not necessarily their absolute number or size - though if you've got a particularly long one it can be a sign of problems, but whether the number of cracks is growing and/or the existing cracks are getting longer and/or wider.
A new crack should be monitored over a few days/weeks to see if it gets longer and/or wider and how quickly. If it's changing quickly then call in an expert sooner rather than later.
Who's an "expert" in these cases? Well for less serious cracks a builder should be able to advise you. For larger, wider, deeper cracks I'd go for a surveyor as they'd be more experienced in this area and should look harder for the underlying cause. A decent builder should also recommend a surveyor if they think things are particularly bad.