Cathedral Grain
Cathedral grain is the arched, pointed pattern of growth rings visible on the face of flat-sawn lumber, resembling the pointed arches of a gothic cathedral. It occurs because flat-sawing cuts tangent to the growth rings, revealing their curved shape as peaked, nested arches. It is the most common grain pattern in construction lumber.
In-Depth Explanation
When a log is flat-sawn (also called plain-sawn or through-and-through), the saw cuts parallel chords across the circular cross-section of the log. Boards cut through the center of the log, where the saw runs tangent to the growth rings, display the characteristic cathedral pattern — a series of nested, pointed arches that form an inverted V or flame-like pattern on the board face. Moving away from the center of the log, the pattern transitions from pronounced cathedrals to straighter, more parallel grain as the saw angle approaches the radial plane. Cathedral grain is perfectly normal and not a defect, but boards displaying it are less dimensionally stable than quarter-sawn or rift-sawn boards because of differential tangential versus radial shrinkage. Many woodworkers and designers prefer the bold visual statement of cathedral grain in species like ash, oak, and Douglas fir, while others prefer the subtler, straighter grain of rift or quarter-sawn material.
Usage Example
The designer chose flat-sawn white ash for the conference table because the bold cathedral grain pattern added visual drama to the large surface.