0808 164 9014


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0808 164 9014


Black Ash UPVC Internal Window Sill Cover Square Edge




Inc. VAT


Please choose required width here: 150mm Square Edge


Black Ash UPVC Square Window Board & Sill

With the authentic look of wood, our Black Ash UPVC Square Window Board & Sill benefits from a scratch and stain resistant laminated finish. It is manufactured for both durability and style. Unlike traditional alternatives, this product will never rot or shrink - and you will never have to paint it. Our customers buy this product because it looks good anywhere, yet requires virtually no maintenance.

Simple to install, this black ash UPVC window board and sill can be trimmed to size with hand tools. Delivering years of high-performance, it will only ever need cleaning. We stock matching end caps for a professional finish.


Available Sizes

  • Length: 5000mm
  • Width:150mm, 175mm, 200mm, 225mm, 250mm, 350mm and 450mm
  • Thickness: 9mm

Product Specifications

  • Won’t fade or ‘bleach’
  • 10 year manufacturer’s guarantee
  • Class 1 fire resistance rating, meaning it won’t burn
  • Fully recyclable
  • Non-toxic


Use this product internally to replace rotting or warped wood or in new-builds. Guaranteed to look good anywhere, this window board and sill is suitable for every room in the home, as well as summerhouses, conservatories and garden offices, and can also be used in commercial properties.


Buy Black Ash UPVC Square Window Board & Sill Online

Lock in a low price by ordering online now. We deliver to any location in mainland UK in 1 to 3 working days. We also offer free technical advice to ensure you buy the right product for your project.