A wall stud may become bowed in your home due to several reasons. Many involve moisture or dryness in the walls, or that the structural weight above the studs is too great. Check out these 4 reasons why a wall stud might become bowed.
Moisture and Dryness
Wall studs are most often made of wood. When wood gets wet it swells and shrinks as it dries. Buildings framed in the winter and spring may develop bowed wall studs because the wood did not dry thoroughly before insulation and exterior wall cladding were put on. Nowadays, however, lumber is readily available kiln-dried from your local suppliers.
Wall studs can also bow if the upper floors and roof structures are too heavy to be supported. Check the wall studs and the load they are rated for before adding an additional floor or enlarging the attic of your home.
There is a belief that wood also expands when it is warm and shrinks when it is cold, that insufficient insulation between wall studs and exteriors like aluminum siding or brick will cause studs to bow due to uneven temperatures on the inside and outside faces, but this is just a myth since the dimensional change would be unnoticeable.
An old house may have a balloon frame. The entire weight of the house may be resting on just the main floor or basement walls, rather than being supported by the floors.