A window pediment is the same element as a door pediment, applied above a window's head casing. The pediment adds a classical architectural feature to the window, and it's used in formal traditional interiors.
The most common window pediment is the straight pediment. A horizontal element with a small profile, applied above the window's head casing. The straight pediment is the most restrained option, suitable for transitional interiors.
A second common window pediment is the triangular pediment. A triangular shape with two sloped sides, applied above the window's head casing. The triangular pediment is the classical Greek signature, used in formal traditional interiors with a Greek or Roman vocabulary.
A third common window pediment is the segmental pediment. A curved shape with a single arc, applied above the window's head casing. The segmental pediment is a Federal and Georgian detail, used in formal traditional interiors with a Federal or Georgian vocabulary.
A fourth common window pediment is the small cornice. A simple cornice element applied above the window's head casing, with a stepped or cove profile. The cornice is the most restrained overdoor element, used in transitional and traditional interiors.
For sourcing, PU window pediments are a stock product at most factories that produce classical trim. The pediments are available in a range of standard designs and sizes, with quick lead times and competitive pricing. Custom designs are available on longer lead times.
A practical install note: the window pediment is installed the same way as a door pediment, with construction adhesive and screws into the wall studs. The pediment's width is typically slightly wider than the window's head casing, with a small projection on each side.
A practical note on the right pediment for the right window. The pediment's design should be coordinated with the window's other trim and the room's overall style. A triangular pediment in a Federal room reads as a stylistic mismatch; a straight pediment in a Greek Revival room reads as understated. The selection should be deliberate, and the pediment should be part of the room's overall composition.
---
Frequently Asked Questions
Q: What is polyurethane (PU) decorative material?
A: Polyurethane (PU) decorative material is a high-density closed-cell polymer molded into architectural profiles such as cornices, ceiling medallions, wall panels, columns, and skirting boards. It replicates the appearance of plaster, carved wood, or stone at one-quarter the weight, is fully waterproof, impact-resistant, and arrives factory-primed for paint.
Q: How does PU compare with plaster and wood mouldings?
A: PU is lighter than plaster (no scaffolding required), impact-resistant during transport, and immune to cracking. Compared with wood, PU does not warp, split, or attract termites, and it tolerates moisture in bathrooms and kitchens. The trade-off: PU cannot be refinished the way solid wood can, but its lifespan is 20–30+ years with minimal maintenance.
Q: How do you cut and finish PU mouldings?
A: Cut PU mouldings with a fine-tooth miter saw (40+ teeth for a 10-inch blade) to avoid chipping the molded edge. Sand the cut edge with 220-grit, then apply two coats of interior latex paint. Mitre joints at corners, fill seams with lightweight spackle, sand smooth, and finish with one final top coat.
Q: Is PU moulding safe for indoor air quality?
A: Yes. Premium PU mouldings are manufactured without formaldehyde, asbestos, or VOCs. They meet EN 13501-1 Class E fire classification as a minimum, with Class B fire-retardant versions available for commercial projects. The factory-applied water-based primer further reduces off-gassing once installed.