A continuous groove or slot cut into masonry or concrete to receive and secure flashing, providing weatherproof connections at building joints.

A reglet is a continuous groove, slot, or channel cut or formed into masonry, concrete, or other building materials to receive and secure flashing, sealants, or other weatherproofing materials, creating weatherproof connections at critical building joints and transitions. This essential building detail provides a mechanical anchor point for flashing systems while creating a clean, professional appearance at the intersection of different building materials or components, ensuring long-term weather resistance and preventing water infiltration at vulnerable building envelope locations. Reglets are fundamental components in commercial and institutional construction where proper flashing installation is critical for building performance, typically formed during construction or cut after completion to accommodate various flashing types and installation methods, making them essential elements in comprehensive building weatherproofing strategies.

Reglets are utilized in various building weatherproofing applications including roof-to-wall connections where reglets secure flashing that bridges the transition between roofing systems and vertical wall surfaces, parapet wall details where reglets anchor cap flashing and through-wall flashing to prevent water penetration, window and door installations where reglets provide secure attachment points for head flashing and sill flashing systems, expansion joint sealing where reglets accommodate structural sealants and weatherproofing materials that must accommodate building movement, curtain wall systems where reglets secure perimeter flashing and weatherproofing at the interface between glazing systems and structural elements, and specialty applications such as equipment penetrations, architectural features, and building additions where weatherproof connections are required between different materials or systems. Each application requires specific reglet dimensions and installation methods appropriate to the flashing type and performance requirements.

The types and construction methods for reglets include cast-in-place reglets that are formed during concrete or masonry construction using temporary forms or inserts that create the required groove dimensions, saw-cut reglets that are cut into existing masonry or concrete using specialized saws after construction is complete, providing precise dimensions and clean edges, surface-mounted reglets using metal or plastic strips that are mechanically fastened to building surfaces to create the required groove profile, mortar joint reglets that utilize existing mortar joints in masonry construction, with joints raked out to the required depth and profile, and specialty reglets including flexible reglets for curved surfaces, fire-rated reglets for fire-resistive assemblies, and custom reglets for unique architectural or performance requirements. The choice of reglet type depends on construction sequencing, material compatibility, and performance objectives.

Fun Fact: The term “reglet” comes from the French word “réglette,” meaning a small ruler or strip, reflecting the precise, linear nature of these building details that have been used in masonry construction for centuries.