Why Pilkington K Glass™ is the Gold Standard for Secondary Glazing.

Posted on 21st April 2026 at 18:59

If you live in a period property or a listed building, you’re likely familiar with the "winter chill" that stubborn draft that seems to cut right through your beautiful original windows. While replacing those windows often isn't an option due to planning restrictions or cost, secondary glazing offers a brilliant workaround.

But not all glass is created equal. If you want to maximize your thermal performance, there is one name that stands above the rest: Pilkington K Glass™. What is Pilkington K Glass™?

Pilkington K Glass™ is a "low-emissivity" (low-e) coated glass. Unlike standard float glass, it features a microscopically thin, transparent coating on one surface. This coating is designed to reflect heat back into the room, making it an incredibly powerful tool for home insulation.

Secondary Glazing Cost & Buying Guide

Posted on 24th February 2026 at 19:07

Upgrading your home’s efficiency doesn’t always mean ripping out your original windows—especially if you live in a period property or a conservation area. Secondary glazing is the "hidden hero" of home improvement, offering a way to slash energy bills and silence street noise without the mess or cost of full double glazing.

Here is your comprehensive 2026 guide to secondary glazing costs, styles, and what to look for before you buy.

What is Secondary Glazing?

Unlike double glazing, which replaces your entire window unit, secondary glazing involves adding a slim, second pane of glass (or high-grade acrylic) to the interior side of your existing window.

It creates a "buffer zone" of air that acts as a powerful insulator. In fact, if you’re looking for noise reduction, secondary glazing often outperforms standard double glazing because the larger air gap (100mm+) acts as a superior acoustic dampener.

2026 Cost Breakdown.

Secondary glazing Chelmsford

Posted on 2nd February 2026 at 19:37

Bringing Classic Charm to Life: Vertical Sliders in Chelmsford

Chelmsford is a city where history meets modern convenience. From the stunning architecture near the Cathedral to the Victorian terraces lining the streets of Old Moulsham, many homeowners face a common dilemma: how do you keep your home warm and quiet without replacing those beautiful, original sash windows?

We recently completed a project in a stunning period property right here in Chelmsford, Essex, where the solution was simple but effective: Vertical Sliding Secondary Glazing.

The Challenge: Draughts and Noise

The homeowners loved their original timber sash windows—and who wouldn’t? They are a defining feature of the property's character. However, like many single-glazed sash windows, they were letting in more than just natural light. The owners were struggling with:

* Heat Loss: Chilly Essex winters were making the front lounge uncomfortable.

* Traffic Noise: Being close to a busy route meant the hum of commuters was a constant guest.

* Conservation Restrictions: As the home is in a sensitive area, full window replacement was either too costly or restricted by planning guidelines.

Why Secondary Glazing Is Important in a Conservation Area

Posted on 2nd December 2024 at 16:57

In conservation areas, strict regulations mean changing windows in a conservation area isn’t always straightforward. That’s where secondary glazing becomes the perfect solution. It allows you to preserve the charm of listed buildings without compromising the original conservation windows.

At NRG Glass, we specialise in solutions that respect heritage while bringing modern benefits such as energy efficiency and home comfort. This article explores why secondary glazing is so important in these cherished spaces.

A Guide to Window Styles for Secondary Glazing

Posted on 29th August 2024 at 09:21

Secondary glazing is an internal window installed alongside your existing one, not replacing it. It effectively reduces condensation, banishes noise pollution, improves insulation, is easy to install and comes in many forms.

Secondary glazing is ideal for historic buildings, modern homes and flats, though it can also be used in businesses and industrial lots. When we say secondary glazing is the best choice, we truly believe it. So, which window styles are best suited for secondary glazing?

Does Secondary Glazing Reduce Noise?

Posted on 2nd July 2024 at 10:47

There is nothing worse than being kept awake by owls or losing out on work because of construction noise. If you’ve had enough, we urge you to invest in our soundproof secondary glazing and learn how it works within this guide.

Everything to Know About Secondary Glazing for Listed Buildings

Posted on 22nd April 2024 at 09:37

Is your property getting colder and colder as the years go by? That could be because you have the wrong windows! But we understand the attachment you have to your listed buildings' original windows. So, instead of replacing them, consider secondary glazing.

How Can I Stop Condensation on Windows?

Posted on 29th February 2024 at 16:22

Condensation doesn’t just hinder you from getting ready in the morning, but can be detrimental to your health. However, not everyone has the time to wipe clean all their glazing each day, so what else can be done to stop condensation on windows for good?

In this article, we will discuss how to reduce condensation on windows, the detrimental effects of it, and what causes it.

Everything you Need to Know About Maintaining Secondary Glazing

Posted on 21st February 2024 at 14:01

Secondary glazing is an internal secondary window. It works alongside your existing window and prevents the need to replace it, but while there are some major benefits of secondary windows, there’s still the need for regular maintenance.

How Insulating Windows for Winter Will Save You Money

Posted on 23rd November 2023 at 08:54

If you pay your own energy bills, or contribute to them, you know the struggle of winter inflation. While you can wrap up under the covers with a hot beverage and comfort food, it doesn’t provide the same warmth your heater does. But the cost of constant heating amounts, so what can you do to prevent this?

Want to know how to keep heat in your house? Read on to learn how to save on energy bills and check for poorly insulated windows.