Timber Box Sash Windows

Timber Box Sash Windows

A timber box sash window is the traditional sash that most people know.

Designed to replace the originals found in many Georgian and Victorian houses, weights & pulleys ensure the windows are easier to open, energy efficient, secure and soundproof without looking out of place for the style of the property.

As the whole process from design to manufacture is with Patchett Joinery, we can ensure the finished product accurately replicates the original style.

Our box sash window operates on sash cords, pulleys and sash weights.

  • Eco-Friendly Products
    Eco-Friendly Products
  • Extensive Guarantee
    Extensive Guarantee
  • Energy Efficient
    Energy Efficient
  • British Manufacturer
    British Manufacturer
Design Features


  • Weights and Pullies – traditional design where weights counter balances the weight of the sash.
  • Independently tested
  • Guaranteed performance
  • The smoothest operating sash window system
  • Internal beading
  • Double draught sealed to maximise thermal performance and weather proofing
  • Lockable fitch catch, traditional in its appearance, when closed it pulls the two sashes together to engage the seals fully


  • Traditional hardware with improved security options, concealed locking and travel restrictors
  • Safety restrictors to limit opening of sash, can be self-resetting
  • Concealed trickle ventilation – when required for new build situations our design conceals the trickle vent into the head of the frame, externally the vent is almost invisible and is concealed internally by the head rebate
  • Traditional sash lifts and sash eyes available in a large range of colour options
  • Vent lock – these devices provide additional security and peace of mind in that the window cannot be opened more than 100mm without them being removed
  • Angel lock – as with the vent lock, this device limits the travel of the sash. The advantage is, when the sash is subsequently closed, the device resets. When the sash is next opened, the restrictor stops the movement of the sash more than 100mm.
Paint Process

first-primer2compressed patchett-joinery-paint-process-compressed

Using only a water-based painting system which allows timber to “breathe” and adapt to climatic changes, our finishes provide maximum protection against weathering, fungal attack and UV degradation. The water-based application significantly reduces harmful emissions and disposal issues associated with solvent based systems.

Working with our paint partner, Remmers, we can finish in any RAL colour, stain, or match against all well known paint ranges and brands. With the ability to have different internal and external finishes, your windows and doors can be finished just as you require.

Our factory is audited quarterly to ensure that the finished product has the highest quality paint finish and performance you would expect.

Hardware Accessories
  • Solid Sash Lift

    Solid Sash Lift

  • Cast Sash Lift

    Cast Sash Lift

  • Pressed Sash Lift

    Pressed Sash Lift

  • Push Lock

    Push Lock

  • Angel Lock

    Angel Lock

  • Round End Sash Stop

    Round End Sash Stop

  • Cill Lock

    Cill Lock

  • Solid Ring Pull Sash Lift

    Solid Ring Pull Sash Lift

  • Ring Sash Lift

    Ring Sash Lift

  • Mighton Fitch Fastener Locking

    Mighton Fitch Fastener Locking

  • Croft Lockable Fitch Fastener

    Croft Lockable Fitch Fastener

  • Sliding Sash Fitch Fastner

    Sliding Sash Fitch Fastner

  • Sash Pullies

    Sash Pullies

  • Vent Lock

    Vent Lock

Timber Options
  • Accoya


  • Engineered Redwood

    Engineered Redwood

  • Red Grandis

    Red Grandis

Glass Options
  • Planitherm Total+ and Low Emissivity (Low E) Glass

    Planitherm Total+ and Low Emissivity (Low E) Glass

  • Standard Glass

    Standard Glass

  • Toughened and Laminated Glass

    Toughened and Laminated Glass

  • Low Iron Glass

    Low Iron Glass

  • Wired/Fired and Pyro-Tech Glass

    Wired/Fired and Pyro-Tech Glass

  • Anti – Sun Glass

    Anti – Sun Glass

  • Acoustic Glass

    Acoustic Glass

  • Obscure Glass

    Obscure Glass

  • Decorative Glass

    Decorative Glass

  • Leaded Glass

    Leaded Glass

  • Gas


  • Spacer Bars

    Spacer Bars

Technical Downloads and Product Brochure

Patchett Product Guarantee

All our timber box sash windows  come with fantastic guarantees giving you the assurance that our products are made to last. All sash windows and doors we make and supply are engineered using the highest quality materials and will require minimum routine maintenance.

  • 30-year* manufacturer-backed guarantee against rot. (50 years with Accoya*)
    5-year* manufacturer-backed guarantee for paint on factory finished windows (Up to 12 years with Accoya*)
  • 10-year* manufacturer-backed guarantee on weather seals
  • 10-year* manufacturer-backed guarantee on double-glazed units
  • 5-year* manufacturer-backed guarantee on hardware