uPVC Windows in Surrey, Hampshire & Berkshire

Traditional Beauty with Modern Performance

Our Deceuninck heritage flush sash windows are expertly crafted to blend the charm of classic timber joinery with the precision and durability of modern uPVC flush casement windows. Designed so the sash sits perfectly level with the outer frame, these windows offer beautifully clean sightlines, balanced proportions, and a refined finish that enhances any Bracknell, Slough, Guildford, Henley-on-Thames, High Wycombe, or Marlow property type, from period properties and cottages to modern townhouses and contemporary new builds.

Authentic Timber-Look Craftsmanship

The Deceuninck flush sash system provides an exceptionally authentic timber aesthetic, making it ideal for homes that must meet conservation area requirements or for those wanting a faithfully traditional appearance. Slim frames, mechanical joints and detailed woodgrain textures recreate the look of handcrafted timber, while high-quality Deceuninck windows and doors engineering ensures long-lasting performance. This perfect combination gives homeowners the character they love without the upkeep timber typically requires.

High Quality Thermal & Acoustic Efficiency

Engineered using Deceuninck’s multi-chambered profiles and advanced weatherseals, our uPVC flush casement windows deliver exceptional energy efficiency. They help minimise heat loss and maintain comfortable indoor temperatures year-round, an essential benefit for both larger homes and compact spaces like a modern townhouse. Superior glazing options also reduce external noise, providing greater acoustic comfort and enhanced peace of mind, especially for properties located near busy roads or public areas.

Secure, Durable and Weather-Resistant

Every Deceuninck flush sash window is manufactured to rigorous industry standards to meet modern security and environmental performance requirements. Reinforced frames and high-security locking systems provide strong protection, while robust seals prevent draughts and water ingress. The low-maintenance PVC-U material will never warp, rot or need repainting, offering reliable, high-quality performance in all weather conditions.

Tailored to Suit Every Property

With more than 30 colourways, including heritage woodgrain finishes like Rosewood, Golden Oak, and Irish Oak, your windows can be tailored to perfectly complement your home. Dual-colour and flush external colour options allow you to choose one shade for the exterior and another for the interior, ensuring a seamless match with both architectural style and interior décor across any property type.

Key Features of Our Flush Sash Windows

• Elegant flush design inside and out
• Market-leading energy-efficient glazing
• A+ rated performance available
• Extensive heritage woodgrain options
• PAS 24 security compliance
• 10-year guarantee for complete peace of mind

Whether enhancing period properties in Bracknell, Wokingham, Ascot or Crowthorne, or elevating the clean lines of a modern townhouse, our Deceuninck heritage flush sash windows deliver traditional beauty, modern engineering and exceptional performance that stand the test of time.

Thames Valley Windows Can Now Price Match

Why pay more? At Thames Valley Windows, you get premium uPVC windows at lower prices — backed by over 40 years of expertise. With our Price Match Guarantee, we won’t be beaten on any like-for-like quote. Same trusted quality. Same exceptional service. Just a better price. T&Cs apply

Trustpilot Reviews

Thames Valley Windows continues to earn excellent Trustpilot reviews from homeowners in Berkshire, Surrey, and Hampshire who value precision installation, stylish product ranges, and exceptional customer service. Whether upgrading sash windows in Bracknell or Guildford, or installing modern aluminium frames in Fleet, customers highlight our professionalism and attention to detail throughout every project.