1. Crack direction
The direction a wall crack runs can give you a good indication of its severity. Wall cracks that run down the wall are usually not a structural threat. Vertical cracks typically form close to where the wall and ceiling meet and tend to follow the same direction as the drywall.
It’s when you have horizontal or diagonal cracks that you should consider repairing or getting an engineer to inspect. Horizontal wall cracks can be the result of shifted foundations and even water damage. If the cracks in your wall are severe enough, the wall of concern may need to be entirely rebuilt.
2. Stair shaped cracks
A diagonal wall crack means there may be some structural damage caused by shifting foundations. Wall cracks that are shaped like a staircase can weaken a wall, making it quite hazardous. If the soil underneath the wall is shifted or displaced, then cracks will begin to separate the bricks or cinder blocks of the wall, thus forming the staircase pattern. An engineer has to do a soil test to determine the extent of the damage and any risk it poses.
3. Visible nails in drywall
Drywalls are nailed to a wooden stud to hold them in place. The dry walls are plastered over or covered in wallpaper, so you cant see the nails. However, when there is a structural shift in your home, these nails can pop out. While having nails poking through the drywall won't cause your house to collapse, they can suggest signs of structural damage elsewhere and shouldn’t be ignored.
4. Misaligned doors and windows
We have all come across a door or window that just doesn’t quite close properly. If you have one of these doors in your house, check to make sure there's no splintered wood or excess paint blocking its path. If the door or window is free of any obstacles but still getting stuck, it may be a sign that the frame has become warped by wall cracks