October 10, 2023

The Shocking Truth About Heat Loss Through Glass Conservatory Roofs

Glass conservatory roofs are notoriously poor insulators. If your conservatory has an ageing glass roof, you could be losing significant amounts of precious heat over the colder months. Just how much warmth escapes through the glass? Let’s take a closer look at some key facts and figures.

Understanding U-Values

When it comes to heat loss, an important metric is the U-value. This measures how well a material conducts heat. The lower the U-value, the better its insulating ability.

Single-glazed glass has a U-value of around 5.0 W/m2K. This means for every 1 degree C temperature difference between the inside and outside, it will lose 5 Watts of heat energy per square meter.

Double-glazed glass is better insulated with a U-value of 2.8-3.0 W/m2K. So it cuts heat loss roughly in half compared to single glazing.

However, the metal frames in a conservatory roof create thermal bridges that reduce insulation. Factoring the frames in, most glass conservatory roofs have an overall U-value of 3.5–4.0 W/m2K.

Estimating Heat Loss

To estimate heat loss, you need to look at the size of the conservatory and the typical temperature difference.

Let’s say you have a 3 metre by 4 metre conservatory, or 12 square metres total.

On a day when it’s 10°C colder outside than inside, that conservatory roof could be leaking 420–480 Watts of heating power per hour based on its U-value.

Over the course of a typical 6-month heating season of around 180 days, that equates to over 1,500 kWh of wasted heat just through the roof.

At 28p per kWh for gas heating, 1,500 kWh of lost heat costs you over £400 extra per year just to keep the conservatory warm!

How Insulation Cuts Heat Loss

Upgrading to a modern, thermally efficient conservatory roof can make a huge difference in reducing heat loss.

While glass conservatory roofs lose around 54% of heat, an insulated solid tile roof cuts that loss to roughly 10%.

Innovative new systems like PanelX take things even further. PanelX conservatory roof panels provide insulation comparable to a solid roof but maintain the bright openness of glazing.

This keeps your conservatory cosier in winter without having to constantly crank up the heating. You enjoy a comfortable space year-round while saving money on energy bills.

Condensation and Mould Growth

Beyond losing heat, poorly insulated glass roofs also commonly suffer from problematic condensation buildup and mould growth.

The air can’t hold much moisture at cooler temperatures. So when warm moist air inside meets the cold glass roof, condensation forms.

This provides the perfect damp conditions for mould to thrive. Older conservatory roofs are especially prone to these issues.

By preventing heat loss, an upgraded insulated roof also reduces troublesome condensation. This creates a healthier indoor environment.

Noise Reduction

Along with retaining heat better, upgraded roofs also provide much-improved noise insulation compared to glass or polycarbonate.

Your conservatory becomes a peaceful, quiet sanctuary. No more hearing the heavy rains or neighbour’s lawnmower when you’re trying to relax!

Added Value

If you ever plan to sell your home, a modern, energy-efficient conservatory roof adds value for potential buyers.

People want livable spaces that are comfortable all year. A conservatory with an upgraded roof becomes a four-season indoor room rather than a temporary sunlight trap.

Before replacing your aging conservatory roof, be sure to accurately measure your existing conservatory and consult local roofing experts on the best options.

But once you see the potential savings in energy, reduction in mould and condensation issues, soundproofing and added comfort, the benefits of upgrading become very clear! Investing in the right roof takes your conservatory to the next level.