half lap joint between parallel boards
A woodworking joint where the edges of two parallel boards are notched to overlap, creating a flush surface. Technical carpentry term.
When you join floorboards with a half lap joint, gaps are less likely to appear.
The side panels of this shelf are assembled with half lap joints.
本実 is a tongue-and-groove joint, which also joins parallel boards but uses a different profile than the notched overlap of 相決り.
Standard kanji spelling for this carpentry term.
Variant spelling using 合 instead of 相.
Abbreviated spelling; less common.
Abbreviated spelling; less common.
Compound of 相 (ai, 'mutual') and 決り (jakuri, 'notch, groove'), referring to the interlocking nature of the joint. The exact historical derivation is uncertain, but the term is established in traditional Japanese carpentry.