What are MDF window boards?
MDF window boards are internal window sills made from medium-density fibreboard, designed to provide a smooth, stable surface beneath windows. They are commonly used in modern builds and renovations due to their consistent finish, ease of cutting, and suitability for painting.
What are MDF window boards used for?
MDF window boards are used to finish the internal base of a window opening, creating a clean transition between the wall and window frame. They are suitable for both new installations and replacement projects.
Their smooth surface makes them ideal for painting, helping achieve a clean, modern finish across a range of interior spaces.
What size MDF window board do I need?
The correct size depends on the depth of your wall and the desired overhang beyond the window reveal. A small projection past the wall face is typically used to create a balanced, finished look.
Common MDF window board sizes
MDF window boards are available in a range of widths to suit different installations:
- 150mm – standard window reveals
- 200mm – most common all-round size
- 250mm – deeper walls and modern finishes
- 300mm+ – larger projections or feature sills
- 400mm – wide reveals and bespoke applications
MDF vs timber window boards
MDF window boards offer a smooth, consistent surface that is easier to paint and finish compared to natural timber. They are ideal where a clean, modern appearance is required.
Timber window boards provide a more traditional look but may require additional preparation and can vary in appearance between pieces.
Common mistakes when fitting window boards
- Choosing a board that is too narrow for the wall depth
- Not allowing enough overhang
- Failing to support the board properly
- Not sealing or finishing cut edges
FAQs
Are MDF window boards suitable for all rooms?
MDF window boards are suitable for most internal rooms, including living spaces and bedrooms. In areas with higher moisture levels, moisture-resistant MDF is recommended to reduce the risk of swelling.
Can MDF window boards be painted?
MDF window boards are ideal for painting due to their smooth surface. Proper priming and sealing will help achieve a durable, high-quality finish.
Do MDF window boards need sealing?
MDF window boards should be sealed, especially on cut edges, to prevent moisture absorption and maintain long-term durability.
Are MDF window boards easy to cut?
MDF window boards are easy to cut using standard woodworking tools, making them suitable for both trade and DIY installations.