There’s no denying that adding a glass extension to your home can give you an impressive architectural feature that will complement any building period or style. While it can add considerable space, flooded with natural light, it will also add significant value to your home. But for some, there can be concerns that your extension can be subject to summer and winter temperature extremes. Beautiful structural solar glass relieves this issue, so your glass extension stays comfortably warm. So is solar glass worth it? This expert guide covers all the details about solar glass: what it is, how it works, and why we use it in all our glass box extensions.

What is solar-coated glass?

Solar-coated glass (or ‘solar glass’) is a technologically advanced type of glazing. A special, multi-functional coating, developed to allow maximum sunlight to pass through it, deflects much of the sun’s heat and radiation. This coating helps your glass extension remain flooded with light while keeping temperatures comfortable and consistent throughout the year.

While the solar-coated glass is transparent, it can have a colour tint applied to it, giving it a unique finish to suit your taste and environment. But whether clear or coloured, the primary purpose of solar-coated glass is to provide glare reduction, UV protection, thermal insulation, and energy efficiency.

How does solar-coated glass work?

Solar-coated glass is essential for regulating the temperature of your inside space and preventing it from being too hot in summer and too cold in winter. With the coating applied to the internal face of the external glazing, it reduces the amount of short-wave solar heat that travels through the glass. This process reduces heat levels inside and reflects solar heat back out, keeping your living space at a more balanced and consistent temperature during hotter months.

At the same time, the solar glass coating reduces internal heat loss by reflecting heat waves back into your space, helping maintain a comfortable indoor temperature during colder months. With various solar glass coatings available, GlasSpace recommends SunGuard® SuperNeutral™
SN 70/37, which reduces the solar factor (g value) to 37% while maintaining visible light transmission at 70%.

Is solar-coated glass worth it?

Your choice of glass for any extension depends on personal taste and, of course, budget. But is solar glass worth it? Solar glass can be expensive, especially when your glass extension could have other suitable options for effective shading during the summer, such as bespoke blinds.

But the visual aesthetic you achieve straightaway makes solar glass worth the expense. Complete glass box extensions have a stylistic design that allows you to indulge in an impressive, minimalist architectural structure that offers you all the benefits of outdoor living with indoor home comfort – without covering it up.

Aside from the visual aspects, solar glass extensions can provide in-built temperature control for temperate conditions. So if your budget can include solar-coated glass, it makes it more likely to become a space you can use all year round.

The benefits of solar-control coatings

Standard glass allows a high percentage of visible light, solar heat, and UV radiation to pass through without being absorbed or reflected. That means more light and heat gets in (leading to overheating) and more heat escaping (leading to drops in temperature). That results in an uncomfortable environment and higher energy costs. Solar-coated glass, on the other hand, does the reverse. Here are the key benefits of installing this premier architectural glazing:

Optimum light transmission

High-performance solar-coated glass allows a light transmission of 70% for excellent levels of natural daylight.

Reduced solar glare

The solar-coated glass allows the sun’s solar glare to be filtered, making bright sunlight easier on your eyes.

Greater UV protection

The multifunctional solar coating reflects many of the sun’s harmful UV rays reducing what comes through the glass.

Reduced solar heat

The solar factor of 37% means that even on the sunniest days, transmission from the sun’s heat reduces, so your space doesn’t overheat.

Reduced furniture fade

The reduced solar glare and improved UV protection preserve furnishings from sun damage and colour loss or fade.

Common SuperNeutral™ solar-coatings

As mentioned above, GlasSpace uses and recommends SunGuard® SuperNeutral™(SN) SN 70/37, to reduce the solar factor to 37% and maintain visible light transmission at 70%. But plenty of different SN coatings are available, providing you with differing levels of light transmission and solar control, including:

• SN 29/18: 29% Light transmission / 18% Solar factor
• SN 40/23: 40% Light transmission / 23% Solar factor
• SN 51: 51% Light transmission / 27% Solar factor
• SN 63: 63% Light transmission / 33% Solar factor
• SN 70/35: 70% Light transmission / 35% Solar factor
• SN 70/37: 70% Light transmission / 37% Solar factor
• SN 75: 75% Light transmission / 40% Solar factor

While each option has low solar U-values, they are available in various colours and appearances to suit your personal needs and tastes.

When is solar control necessary?

While there’s much talk about solar control, it’s a necessity rather than a luxury for all glass box extensions. With the climate emergency, temperatures can rise steeply in the summer months. And if your extension is made entirely of glass for greater natural light, it increases the internal temperature of the space more quickly, causing discomfort and overheating.

But it doesn’t mean you need to compromise on thermal comfort. When solar-coated glass is used, you have a reduced solar factor, so your space doesn’t feel too hot. And if you use air conditioning or central heating throughout your home, you’ll be able to maintain a consistent temperature allowing you to use your extension fully, all the time.

Why GlasSpace uses 70/37 solar-coated glass

We feel SunGuard® SuperNeutral™ SN 70/37 is the optimal light transmission and solar factor level to benefit all installations and to give complete control over your extension’s internal temperature. But this type of glass, and certainly the full SunGuard® glass range, is regularly specified by architects and homeowners to ensure ongoing energy savings and solar and thermal protection.

Superior solar-controlled glass from GlasSpace

This guide will give you a good understanding of solar glass and how it works in a glass box extension while answering your question of ‘is solar glass worth it?’.

As designers and suppliers of specialist frameless glass box extensions and certified professionals, our team has the knowledge and experience in solar-coated glass and can help you with expert consultations and installation details you need. Contact us today for more information and your no-obligation, free quote.