Mouldings

Spectis mouldings are high-density polyurethane trim for the lines of a room and the outside of a house. This category covers crown, base, casing, chair rail, window sill, brick mould, flat stock, and dentil. The detail is cast in the mold. Sticks ship primed white, ready to paint, for interior or exterior. Use PLP100 on every bedding face and butt joint. Other adhesives can attack the urethane. Cut and fasten with ordinary woodworking tools.

What size crown to order

Crown fails when it is too small for the wall or too deep for the soffit. Height is the vertical face. Projection is how far it comes off the wall. Both numbers are on the cut sheet for that profile.

Confirm the cut-sheet height against the actual wall. These ranges are a start, not a substitute for the plate.

Rules that survive a catalog

An 8-foot ceiling with a 7-inch crown looks top-heavy unless the room is wide or the ceiling is trayed. A 12-foot foyer with a 3-inch cove looks unfinished. Exterior cornice is sized to the eave, not to the room inside. If the overhang is 12 inches, do not order a 16-inch projection and hope.

Spring angle is profile-specific. The compound miter on a 38-degree crown is not the setting for every Spectis stick. Use the angle on that SKU’s cut sheet, or cope the inside corners if your saw work is stronger that way.

Build-ups change the math. A crown cap over flat stock over dentil can be the right size even when no single stick matches the chart. Read crown cap, crown with flat stock, and 2 step crown before you invent a stack from loose lumber.

Order length from the actual perimeter plus waste for miters, not from a room’s longest wall. A 12-foot stick does not finish a 12-foot wall once both ends are mitered. Most crowns are 12-foot sticks. A few decorative profiles are closer to 139 inches.