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Flush Sash Casement Windows in uPVC

Modern flush sash windows combine the flush style of timber windows with the environmental performance and low maintenance uPVC. Offered with advanced EcoMAX glass or Comfort Glass, flush sash windows improve your home’s thermal performance and visual appeal. Choose from a range of colour and woodgrain finishes including popular shades like Anthracite Grey, Agate Grey, and Olive Grey.

A range of handle styles is also available including standard, traditional or contemporary all with secure locking.

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    White uPVC flush sash bay window

    Sitting flush

    The opening sash of the window fits flush with the outer frame for a seamless appearance

    Hidden Corner Weld

    An unseen corner joint helps create a seamless look. Choose from a fully welded, full mechanical or MechWeld joint

    Identical sightlines

    Enhance your home with same-width frames for equal sightlines

    What is a flush sash window?

    Precision made to replicate the look of timber, flush sash windows fit neatly into the window frame instead of fitting proud. Made from uPVC, they offer improved energy performance over timber alternatives, better weatherproofing, and low maintenance and are also considerably cheaper. Well-known for traditional aesthetics without the drawbacks, even the keenest eye will struggle to tell the difference!

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    What flush sash windows can do

    Inexpensive visual alternative to timber

    Much cheaper than timber, our uPVC flush sashes can be customised in three realistic jointing options; fully welded, full mechanical, or mechanical/weld.

    Improved thermal insulation

    Available with three, five or six insulating chambers, our multi-chambered uPVC flush sash windows attain energy A ratings.

    Exceptional home security is locked in

    Able to last up to 35 years, our heritage uPVC windows include heavy duty components

    Low maintenance

    Our uPVC flush sash windows offer a maintenance-free design that won't rot, crack, warp, or fade throughout their lifespan.

    10 years’ product guarantees

    All new windows carry a standard guarantee for 10 years on fit, function and finish.

    Environmental protection

    As well as offering EcoMax Glass, our uPVC flush sash windows incorporate a recycled section and are fully recyclable.

  • Colours
  • Glazing
  • Frame Options
  • Furniture
  • Additional Features
  • Colours

    An array of finishes is available including white, natural, oak and cream.

    White

    White

    Clotted Cream

    Clotted Cream

    Pearl Grey

    Pearl Grey

    Chartwell Green

    Chartwell Green

    Elephant Grey

    Elephant Grey

    Slate Grey

    Slate Grey

    Slate Grey Grained

    Slate Grey Grained

    Basalt Grey

    Basalt Grey

    Anthracite Grey

    Anthracite Grey

    Anthracite Grey Grained

    Anthracite Grey Grained

    Black Brown

    Black Brown

    Steel Blue

    Steel Blue

    Racing Green

    Racing Green

    Ruby Red

    Ruby Red

    Turner Oak

    Turner Oak

    Irish Oak

    Irish Oak

    Golden Oak

    Golden Oak

    Rosewood

    Rosewood

    Mahogany

    Mahogany

    Walnut

    Walnut

    Dark Oak

    Dark Oak

    Glazing

    Our uPVC and aluminium windows come with EcoMAX Glass™, one of the most sustainable glass units on the market. You can also choose Comfort Glass for higher levels of thermal efficiency, security and noise reduction, or decorative glazing, such as stained glass, floral patterned, or modern etched glass.

    Frame Options

    Choose the perfect profile for your finished window

    Choose from chamfered, a contemporary, straight-edged style, ovolo, a more traditional, decorative finish or flush sashes that blend with the external face of the window.

    Ovolo Frame

    Ovolo Frame

    Flush Sash Frame

    Flush Sash Frame

    Chamfered Frame

    Chamfered Frame

    Furniture

    Authentic furniture for your sliding sash windows

    A range of window furniture options adds a personal touch to your windows. Choose from elegant designs for handles and window restrictors and pegs.

    Furniture Handle Options

    Window Handle

    Window Handle

    Pear Drop Handle

    Pear Drop Handle

    Monkey Tail Handle

    Monkey Tail Handle

    Furniture Colour Options

    Black Finish

    Black Finish

    Brass Finish

    Brass Finish

    White Finish

    White Finish

    Chrome Finish

    Chrome Finish

    Steel Finish

    Steel Finish

    Additional Features

    Authentic Timber Look Cill

    Radlington Cills are deeper nosed cills, one at the standard 30mm height and another at a 55mm height; they are reproductions of timber cills.
    Window with a white cill

    Overhead Ventilation

    In overhead, concealed ventilation the external trickle vent is hidden on the head of the outer frame, providing a much-improved finish.
    Window with an overhead concealed vent

    Versatile flush sash window designs

    Small details have a big impact on the appearance of your home. Flush fitting windows are a key one—drawing a distinction from the more common proud or overlapping style.

    We offer flush sash windows with fully welded, full mechanical, or mechanical/weld joints to create a style that will perfectly complement your home’s existing character. You can make them more distinctive with a variety of timber-replica finishes and classic extras like Georgian bars, decorative glass, or leaded details.

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    Golden oak flush sash casement window
    Close up of flush sash window

    Can you put UPVC windows in a conservation area?

    If you live in a in listed building or a conservation area you must take extra care that window and door replacements do not depart from the existing design. It is advisable to check with your local planning office before making any changes.

    These flush sash windows are designed with quality of appearance in mind. Features such as detail in replicating traditional joinery add to their genuine appearance and mean they are commonly approved for listed buildings and conservation areas where building regulations restrict home improvements.

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    Thermally insulating sliding sash windows

    Our highest-rated double glazed windows have an energy A+ rating (the highest there is). So, you can be sure that they’ll keep the inside of your home at an optimum temperature.

    Efficiency is a result of careful design and engineering. Our windows feature new performance oriented technologies including multi-chambered window profiles, argon-filled inter-pane areas, low-e glass that’s specially treated to reflect heat back into a room, and the newly patented Warm Edge Spacer Bar.

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    Black flush sash window
    anthracite grey flush sash window close up

    What is a window sash?

    A window sash is a frame that holds the glass panes within a window. It is the movable part of the window that can be opened and closed, usually consisting of vertical or horizontal panels that slide or pivot.

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    What is the difference between a casement window and a sash window?

    A casement window is hinged at the side and opens outward like a door, while a sash window has one or more movable panels that slide vertically or horizontally within the window frame.

    Casement windows provide unobstructed views and better ventilation, while sash windows offer a traditional aesthetic and are often found in 18th and 19th century buildings.

    Double glazed window in traditional flush sash style

    Compare window styles

    Heritage Windows

    Heritage Windows

    • Made from uPVC to replicate timber
    • Achieve A++ energy ratings
    • Multi-point locking system

    Popular Colours:

    No. 10 Black
    Eclectic Grey
    Corse Lawn
    White
    Casement Windows

    Casement Windows

    • Available in high-performance uPVC or aluminium
    • U-values as low as 0.8 W/m2K
    • • Multi-point locking system

    Popular Colours:

    Deep Black
    Anthracite Grey
    Smoke Grey
    White
    uPVC Sliding Sash Windows

    uPVC Sliding Sash Windows

    • uPVC authentic timber-alternative sash window
    • U-values of 1.4 W/m²k or lower
    • Multi-point locking system

    Popular Colours:

    White
    Black Brown
    Anthracite Grey Grained
    Elephant Grey
    Bay Windows

    Bay Windows

    • Available in high-performance uPVC or aluminium
    • U-values as low as 0.8 W/m2K
    • Multi-point locking system

    Popular Colours:

    White
    Elephant Grey
    Anthracite Grey Grained
    Black Brown
    Tilt and Turn Windows

    Tilt and Turn Windows

    • Available in high-performance uPVC or aluminium
    • U-values as low as 1.0 Wm2K
    • Multi-point locking system

    Popular Colours:

    White
    Black Brown
    Anthracite Grey Grained
    Elephant Grey
    Conservation Windows

    Conservation Windows

    • Multi-point locking system
    • Achieve A++ energy ratings
    • Multi-point locking system

    Popular Colours:

    White
    Black Brown
    Anthracite Grey
    Elephant Grey
    Bespoke Windows

    Bespoke Windows

    • Available in high-performance uPVC or aluminium
    • U-values as low as 0.8 W/m2K
    • Multi-point locking system

    Popular Colours:

    White
    Deep Black
    Anthracite Grey
    Smoke Grey
    uPVC Windows

    uPVC Windows

    • Robust and durable frames
    • Available in seven styles
    • 20 years life expectancy, maintenance free

    Popular Colours:

    White
    Anthracite Grey Grained
    Black Brown
    Elephant Grey
    Aluminium Windows

    Aluminium Windows

    • Minimalist frames and sightlines
    • Available in four styles
    • Over 30 years life expectancy, minimal upkeep

    Popular Colours:

    Deep Black
    Anthracite Grey
    Smoke Grey
    White

    Your Window and Door Journey with SEH BAC

    Replacing your windows and doors is easy.

    Choose the right windows and doors

    Fill out a form online or visit one of our 10 showrooms to see our range of high-quality windows and doors up close and speak to our expert team for any advice on materials, styles, colours, energy efficiency and glazing. Once you are happy with your choice, we’ll provide you with a free no-obligation quote.

    Place your order with us

    When you want to go ahead with your order, the details have been approved, and we have received your order deposit, our administration team will provide your contract to a surveyor.

    Your surveyor assessment

    The surveyor will contact you to arrange a date that is convenient to come to your home and review the project scope, take accurate measurements and discuss any other matters that need to be considered. We will then confirm the surveyor’s assessment.

    Confirm an installation date

    Our installation department will contact you to arrange a date for your window and/or door installation and your products will be ordered and manufactured, using cutting-edge techniques and industry-leading materials.

    You're ready for your installation

    On the day, our skilled team will arrive at the agreed time to install your products, ensuring minimal disruption. They’ll explain the locking and opening systems and share maintenance tips to keep your products looking brand new. Once your installation is complete, we will contact you to confirm that everything has been finished.

    Two people who identifies as men Installation windows.

    FAQs

    How much will new flush sash windows cost?

    Thermally sound, industry-accredited custom-made windows must be individually priced to take into account manufacturing to size and any features you wish to specify. We offer a range of finance options to spread the cost of new windows. You can read more about what affects the price of double glazed windows on our site.

    How do I know if my windows need replacing?

    There are always obvious signs like poor fit, rot in wood, loose fittings, and inconsistent lock operation, but sometimes it’s just time for a change. New windows can have a big impact on the outward appearance of your home. See our blog for more on this.

    Which window material is best?

    All our windows are designed for visual appeal as well as security, thermal efficiency and durability. Complete with industry-leading and highly accredited hardware, any of our award-winning replacement windows could transform your home. Read more

    What is A rated double glazing?

    Energy efficiency is often the top priority and it’s no wonder as the bills keep rising. The British Fenestration Rating Council (BFRC) rates window energy performance and publishes results to help you decide which windows are best for you. Read more.

    Begin Your Project

    Get your free quote – with no-obligation to buy. Simply fill in the online contact form below to get started:







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      Here at SEH BAC, we’re proud to have won many prestigious awards for our products as well as our work in the community:

      Installer awards 2022
      G21 Finalist
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      Conservatory and orangery awards winner 2019
      NHIC 2018 Consumer confidence award
      G17 Installer of the year
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