Slimline uPVC Windows: Thinnest Double Glazed Windows In The UK

Slimline uPVC Windows

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About Our Slimline uPVC Windows

With windows accounting for up to 30% of heat loss and increasing energy costs, it’s important for you to choose a high-performance double-glazed window which also looks the part.

Why choose modern Slimline uPVC windows?

Traditionally, the only slim frame windows on the market were aluminium windows, while standard uPVC windows had a thicker frame. But drawing on our 40+ years of experience, we have designed our exclusive line of ultra-thin windows in uPVC. With 12% more glass than a standard window, our ultra-slim profile windows are the thinnest uPVC windows in the UK and will fill your home with light for a bright atmosphere inside.

Combining the performance of standard casement windows with spectacular design, our Slimline uPVC windows are sleek and technically impressive. As a Sheerwater exclusive, our slim framed uPVC windows have been carefully designed to complement our full product range. So, if you’re also choosing a replacement door, rest assured it will match your slimline windows perfectly for unbeatable kerb appeal.

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Top Grade uPVC

The highest category (CAT A) outside wall thickness is 2.8mm – our Slimline system is 3mm.

Weather Resistant

Entirely drought proof and watertight, the purposely built drainage system further enhances its weather resistance.

Bespoke Frames

The ultra-thin window frames are tailored to you. You will have a selection of colours, finishes and woodgrain foils to choose from.

Thermal Enhancement

With a multi-chambered system, our Slimline uPVC windows are manufactured for increased thermal efficiency.

Custom Handles

You will have a choice of elegant window handles for an espagnolette window lock, available in an array of colours.

Easy Operation

Our uPVC thin framed windows can open to a 90º angle (conforming to the current British Standards & FENSA requirements), and provides thumb catches; which allow you to open and close the window easily.

Slender Design

With a lower proportion of frame to glass, our uPVC windows eliminate bulkiness and welcome more light into your home.

The Benefits of our Slimline uPVC Windows

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Bespoke Design

Tailor your new Slimline uPVC windows for a unique design. Our exclusive uPVC windows are available in a range of colours to suit any property, including grey, black and Chartwell green. Whether your property is modern or traditional, we’ll create a design to suit your personal preferences.

Our slimline windows can accommodate any of our window furniture pieces and decorative glazing options, so whether it be sleek grey thin-frame windows for a contemporary style, or heritage wood effect slim uPVC windows for an old cottage, the options are endless.

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Energy Efficiency

Our slimline uPVC windows were awarded with a Window Energy Rating (WER) of A+. This impressive energy rating ensures that your home stays warm and dry all year round, and will help to cut the cost of your household bills.

Our range has also been tested by BFRC and has been awarded an energy rating of A+, which is the same as most triple glazed windows and in turn will help lower the costs for your household.

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Exclusive Range

You won’t find our Slimline uPVC windows anywhere else in the UK! They’re exclusive to Sheerwater Glass; so if you’re looking for a thinner frame version of standard uPVC windows, then our collection is for you.

Our friendly team are just a phone call away to help you find the perfect thin-framed window solution for your home, so contact us today! We can advise on the best style and design to complement your home, to make sure they add serious home value and kerb appeal.

Tailored Slimline uPVC Windows in Surrey

Our team of experts are available to help you design and install a bespoke ultra slim profile that looks great and effortlessly complements your home. The opportunity to tailor your windows to suit your home has never been easier than it is with our exclusive range, which offers great customisation options.


Security is of great importance to you, your home and your family, and you can be confident that our stormproof uPVC windows offer maximum security.

We don’t believe in cutting corners, which is why we source and install not only the highest quality products and materials, but most secure too. This is why our range is fitted with Trojan multi-point, shootbolt locking mechanisms to keep your family home safe.

Our Slimline windows are fitted with:

  • A Shootbolt locking system, which utilises a Shootbolt Espagnolette gearbox that is manufactured from ferritic stainless steel. It’s so secure that the locking mechanism has been rigorously tested and achieved BS7950 status.
  • Security glazing to prevent the removal of the glass units, as well as a method to stop water or dampness forming within the unit and glazing.
  • Hinge protection to improve anti-thrust (anti-jemmy) protection.
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Technical Information

Weather Resistance

Your new windows or doors will be completely draught-proof and watertight. The Slimline profile is produced with all weather bubble gaskets (seals), fused to both the inner and outer frame section.

The bubble gaskets are hollow and offer greater compression and remain in-line with the profile for a neater appearance. They are fused to the profile, which means they can never shrink back, reducing the chance of leaks or unpleasant draughts in your home.

Integral Drainage

To enhance the weather resistance further, our uPVC frame system is installed with a purposely built drainage system that directs any water penetration away and towards the external drainage route.

Slender Design & Clean Lines

Whilst all the profiles remain technically the same, the Slimline system offers a choice of Bevelled or Ovolo beading, depending on your preference.

The windows were designed to be symmetrical – with respect of all flat surfaces being similar in width. This ensures that the window is much sleeker and more aesthetically pleasing for your window.

Top Grade uPVC

The European committee standards state that uPVC must have the highest category (CAT A) outside wall thickness of 2.8mm – the Slimline system is 3mm. Together with 5 chambers, it offers superb frame strength and rigidness that will last for years.

How effective is double glazing at reducing noise?

Get a quote or find out more about our range of Slimline Windows

Contact our team today or get a quote using the link below.

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