Nothing beats the look and feel of real wood products. They bring warmth, beauty, and charm that just can’t be duplicated with synthetic building materials. As natural wood lovers, when larger timbers and beams crack and “check” (as they always do), we believe it only adds to the special character and appeal that only natural wood can provide.
When a tree is harvested, about half of its weight is water. Soon after, it begins to dry and shrink about twice as fast along the growth rings than across them.
After it is milled, smaller lumber pieces will dry faster than wood manufactured into larger timbers, beams, or heavier boards. As the outer layers of the bigger pieces dry and shrink, the center of the timbers will stay moist longer. All these changes cause the lumber to move, check and crack. The larger the timber or beam, the larger the cracks, as well.
This is NOT a bad thing!
Checking normally begins on the exterior surface of a timber and is not a structural concern. In fact, because it releases the tension that has built up, it actually makes the wood stronger.
All wood species will check differently. Denser exotic woods check more readily than softer woods, such as Douglas Fir and Cedar. However, checks in harder woods are generally smaller.
Ways to help minimize checking:
- Generally speaking, higher grades of materials will have more stability. Especially when choosing “free of heart center” instead of “boxed heart” grade (as applicable)
- When building with Douglas Fir, and some other hardwood species, some larger timbers and beams can be kiln-dried.
- Use proper acclimation techniques. Store your wood off the ground, out of direct sunlight, and allow the ends to breathe prior to installation
- Seal cut ends of hardwood timbers immediately after cutting.
Please note all wood timbers and beams will continue to move; take on moisture, and shrink, especially those installed in exterior applications. Checking on large timbers and beams, in many cases, does not occur until well after it is installed. On a loose rule of thumb, softwood timbers (such as Cedar and Doug Fir) dry about 1” per year. This means it can take 6 years for a 12×12” beam to reach equilibrium to its surroundings, and there will be movement and change throughout the whole process.
Photo and craftsmanship by Minnesota Pergola
Our team of Wood Building Material Specialists are happy to discuss options on timbers and beams with you that are grown in the Pacific Northwest, including Western Red Cedar, Alaska Yellow Cedar, and Douglas Fir.
We ship nationwide!
360.757.6343
950 B Fountain Street, Burlington WA