Cracks and checks give cedar so much of its character. They are a big part of what makes cedar completely unique and different from any other timber in the world!
Cracks or checks occur when wood shrinks as it dries. Wood shrinks roughly twice as much along the growth rings as it does across the rings and it is this uneven shrinkage that causes checks to develop.
Checking can be controlled in smaller sized 4/4 -10/4 lumber, because it’s easier to dry. But when you get into thicker pieces like 12/4 and up to 12×12 timbers, they will retain moisture much longer than the outer layers and will begin to crack.
Are Cracks and Checks Bad?
While extreme loading can cause a wood beam to split and would indicate a sign of impending disastrous collapse, checks and cracking are a natural part of timber frame buildings and add character and uniqueness to your structure. They do not compromise structural integrity and will most likely close or shrink as the timber dries over time. Its just a natural side effect of wood.