Bringing stylishness, comfort and security to your home, our Extreme UPVC Windows are our top performing window.

Our standard UPVC windows are impressive enough, but our UPVC EXTREME windows take things to a different level in terms of the security and energy efficiency they offer. A+ rated as standard for a comfortably regulated temperature, our clever glazing technology prevents internal heat from escaping, whilst harnessing just the right amount of heat from the sun.

Extreme UPVC Windows

After the installation of these EXTREME windows, your home couldn’t be more secure. In addition, locking in heat, out sculpted frames house chambers for added insulation and durability that lasts a lifetime.

To ensure they justify their ‘EXTREME’ tag, we performed hours and hours of testing and they came through each assessment with flying colours. Take EXTREME measures and put your faith in these windows to deliver the very best all-round window performance.

Grey Extreme UPVC Windows
Extreme UPVC Windows


We offer a varied array of UPVC windows, all carrying our signature A+ energy rating as standard. ERG has a very experienced team of window specialists that will listen to your requirements and come with possible window solutions for the project.

Cream UPVC Cottage Windows


As an outward opening window, casement windows can be top hung, or side hung. The Casement window is an effortlessly simple look.

UPVC Tilt & Turn Windows


This innovative and easy to clean European design meets the needs of many homeowners seeking excellent security, air tightness and noise reduction.

UPVC Sash Windows


While in keeping with a classic timber look, the Sash window exudes modern UPVC qualities, such as strength and practicality.



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Do your windows have EXTREME protection?

We are excited to give our customers access to our exclusive EXTREME collection, which combines up to 9 visible locking points, offering you 3 times more protection than a standard window.

  • EXTREME heightened security with centre VAULTBOLT and multi cam locking technology.
  • EXTREME heightened durability with UNIQUE superglide gearbox ensures smooth operation.
  • EXTREME heightened COMPRESSION and acoustics with interlocking hinge bolts and optimum weatherseals.
Casement Windows

Herculean Hinge

Heavy duty, highly engineered hinges that provide increased load bearing. With anti-crowbar technology and sustained use for a lifetime.

Extreme Locking

Up to 9-point locking system and two high compression hinge bolts to create 360-degree solidity. Also available with enhanced security option designed to meet the requirements of the police-recognised Secured by Design initiative.

Extreme Frame

Highly engineered frames, that encompass 14 chambers (combined sash and frame) to provide supreme thermal performance. Maximum protection against twist and ageing so your windows will look and operate like new for longer.

Extreme Weather Seal

Dual density and high elasticity for twice the standard coverage. Long lasting airtight protection from the elements and added noise reduction.

Ultimate Glass

High performance next generation glass for superb energy efficiency. Ultra-clear outer pane and a super soft coat inner pane. Improved clarity for the perfect view.

Extreme Handles

Our Extreme Handles come in a range of colours to suit your home. Built to last with robust materials and quality finishes.
ERG Scotland windows offer maximum energy savings...

ERG’s replacement windows can ensure you notice a drop in your energy bills, saving you money every month. Fortunately, heat loss will become a thing of the past due to our modern, thermally reinforced window profiles.

The Energy Saving Trust has acknowledged our EXTREME windows for their thermal qualities and eco-friendly performance.

White UPVC Windows
Oak Envisage Flush Windows
White UPVC Windows


When you have settled on the right window style for your home, you will need to think about personalising the window to your taste. We offer a vast selection of coloured finishes, glazing choices and hardware to get just the right look.

A huge assortment of colours...

It may take you a little while to settle on a finish for your new EXTREME windows as we have 100’s of shades, textures and wood effects available. You will have absolutely no difficulty finding a suitable finish with so many options on offer as our colour palette incorporates traditional and modern coloured finishes. Chartwell Green is just one of several vintage colours at ERG that is being chosen time and time again by our window buyers.

Glazing comes in many different forms…

The importance of the window frame is matched by the importance of the glazing used. If the main incentive is to reduce the cost of fuel bills you will be best choosing our high performance next generation glass. A quick conversation with one of our window consultants will help you get your glazing right.  Our privacy glass will give you that as it is frosted and will obscure what people looking in can see. It can be supplied double or triple glazed depending on what you would prefer.

Intricately crafted handles...

Our carefully crafted handles come in a series of stunning designs to enable you to make the window your own. Each has been expertly made by highly trained craftspeople and will make opening and closing your new windows effortlessly simple and forever pleasurable.

With a secure locking system built in, you can be confident that when you close your windows they are tightly fastened.