Exterior Window Sills
Protect your masonry and enhance your windows with prestigious, high-density composite sills meticulously designed to deflect water and resist freeze-thaw cycles.
These high-performance profiles offer the authentic look of limestone without the structural weight of stone.
Achieve a permanent, maintenance-free masonry aesthetic with the enduring durability of advanced modern engineering.
Engineered for superior drainage and zero rot, our composite sills outperform traditional wood and masonry. Compare our technical material science against market alternatives here.
Exterior Window Sills Specifications
100% moisture-inert. Will not rot, warp, or crack.
Expertly bonds to Brick, Stone, Stucco, Vinyl, and ICF.
Unlimited profile designs including custom arches and circles.
Mimics smooth-sanded wood or textured masonry with ease
Zero-joint expansion. Engineered for extreme climate swings.
90% lighter than stone. No structural upgrades required.
The 5th Category: Exterior Coated Expanded Polystyrene
For professionals and project owners, selecting exterior trim usually involves four common categories: Cellular PVC, Polyurethane, Fiber Cement, or WPC. However, Mouldex Composites introduces a superior 5th category: Cement Coated Expanded Polystyrene for exteriors.
Engineered to exceed the limitations of standard wood and plastic alternatives, our systems utilize a high-density EPS core, wrapped in an alkali-resistant fiberglass mesh and shielded by a proprietary polymer-modified cement coating for the ultimate durability formula.
This creates an architectural profile 90% lighter than pre-cast concrete while maintaining the authentic "masonry feel" and impact resistance that PVC and Polyurethane (Fypon) lack.
By eliminating high thermal expansion rates, Mouldex ensures a stable, moisture-proof building envelope that preserves architectural integrity for the life of the project.
Our foamcore mouldings are comprised of entirely inorganic materials, resulting in high durability and sustainability without the rotting, cracking, splitting or warping high maintenance issues of wood.
Beyond Pre-Cast & PVC: Exterior Performance Comparison
| Attribute | Mouldex Exterior Mouldings | Pre-Cast Concrete | Wood (Metrie / Alexandria) | PVC / Poly (Azek / Fypon) |
|---|---|---|---|---|
| Weight | Ultra-Light (1/10th weight) | Extremely Heavy | Moderate | Light |
| Durability | Polymer-Cement (Impact Resistant) | Masonry (Brittle) | Prone to Rot/Warp | High Expansion |
| Installation | 1-Person / No machinery | Crane / Structural Ties | Skilled Carpentry | Standard Mechanical |
| Maintenance | Zero Maintenance | Patching / Re-sealing | Painting / Staining | Fading / Chalking |
The 6 Pillars of Evolved Foamcore Technology
100% moisture-inert. Will not rot, warp, or crack.
Expertly bonds to a variety of wall surfaces
Unlimited profile designs including custom arches and circles.
Silky smooth and ultra fine plaster for the ultimate finish.
90% lighter than traditional plaster with better performance.
Zero-joint expansion. Engineered for extreme climate swings.
Mouldex Exterior Composite Engineering & Performance
Exterior architectural mouldings, whether used for window trim, sills, or cornices, play a dual role in both aesthetic enhancement and building protection. At Mouldex, we manufacture a proprietary composite solution designed to solve the inherent failures of traditional masonry and wood materials.
1. The Evolution of Foamcore
Mouldex profiles represent a generational leap in material science. We utilize a High-Density Expanded Polystyrene (EPS) core, wrapped in an alkali-resistant fiberglass mesh and encapsulated in a proprietary polymer-modified cement shield. This creates an inorganic, durbale exterior that is 100% moisture-proof and impact-resistant, engineered to outperform traditional foamcore, pre-cast, wood/MDF, and PVC.
2. Versatile Substrate Compatibility
Unlike traditional trims designed for a single wall type, Mouldex is engineered for Universal Compatibility. Our adhesive-based bonding technology is optimized for a permanent, structural hold on Brick, Stone, Stucco, Vinyl/Siding, and ICF. This eliminates the 0.00003 thermal expansion gaps found in PVC and the moisture rot common in Wood and MDF.
3. Unmatched Customization & Arches
Where rigid materials like PVC and wood fail, Mouldex excels. Our Bespoke Customization allows us to manufacture precision-cut Arches, Full Circles, Ovals, and Ellipticals to match any architectural radius. Utilizing advanced CNC technology, we can replicate historical profiles or create modern shapes with a 7–10 days.
4. Timestone Look Without the Weight
Traditional pre-cast concrete requires expensive structural reinforcement and heavy machinery. Mouldex provides an indistinguishable masonry aesthetic at 1/10th the weight. This Weight Efficiency eliminates the need for cranes or wall-load upgrades, typically providing a 75% total cost savings over stonecast products.
5. Engineered for Freeze-Thaw Cycles
Our proprietary coating is the definitive choice for the Northern US and Canadian climates. While GFRC and fiberglass alternatives often crack under thermal stress, Mouldex is engineered for Zero-Joint Expansion, maintaining its structural integrity through extreme temperature swings.
6. Pro-Grade, Fast-Track Installation
Our Nail-less Installation system utilizes high-bond architectural masonry adhesives. This prevents the building envelope from being compromised by thousands of nail holes and eliminates the risk of rusting fasteners bleeding through your finish over time. For larger shapes, we utilize a rear attachment mechanism for stability and safety.
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