Cracks in My Ceiling (Answer)

Hey Dawn,

From your description of the problem, what you have is a typical case of Truss Uplift. This is not the first time I have had this question. To explain this, I will have to give you a brief explanation of your roof structure.
To start your roof structure is a truss type. To put this simply, the frame for your roof and the frame for your ceiling are all connected, this makes a truss. These trusses are spaced about sixteen to twenty-four inches apart, to span the length of your house. The top wood of the truss is called the upper cord, to that your roof sheathing and shingles are attached. The wood that runs along the bottom is called the lower cord, to that your ceiling is attached.

Trusses structurally span the entire width of the house, there for they require no load-bearing wall in the center. The center wall that divides your rooms is a non-load bearing wall, the lower cords of the trusses simply pass over the wall.

Now getting back to your problem “truss uplift”. This type of cracking or separation wile being unattractive it does not usually indicate a structural problem.

Since the trusses are all one unit connected together to form the ceiling and the roof structure, as the parts cure and shrink all parts of the truss is affected. The wood starts drying and shrinking the attachments that hold the top cord to the bottom cord, causing the bottom cord to crown or raise up in the middle. This causes the ceiling to raise and lift from the center wall, thus causing the cracks between the wall and the ceiling.

In your case, since the house is three years old, the moisture content of the truss members is at a stable level, and will not get worse.

Cosmetic repair of the cracks should take of this problem. In most cases a paintable calk and some paint is an easy and inexpensive cure.

While major and persistent cracking may indicate structural problems, in your case the cracking is a common and normal occurrence in new houses. With new construction it is likely to have slight settling and shrinkage of building materials, which will cause some slight cracking in the corners of your drywall.


Thanks for your question.

Please send questions to agarrett54@hotmail.com Please put "Hey Al" in the subject box.