Posted 5th November 2025
We don’t need to tell you that costs are rising across the UK. From everyday essentials to long-term investments, prices seem to keep climbing with no end in sight. But what if we told you there’s one area where you can take back control and stop one of those costs from spiralling?
One of the most notable costs for any homeowner is energy bills. They’re an absolute necessity for any homeowner, especially as we approach what is expected to be a typically harsh winter where we live.
At Fortis Windows and Doors, we want to help you keep rising costs under control. You may not realise that doors and windows are responsible for as much as 25-30% of total heat loss in a typical home, according to Stay Warm Energy. That’s why it’s essential to understand how your front door should perform to minimise this loss.
Real World savings with energy rated composite doors
When it comes to keeping your home warm and your energy bills down, two terms you’ll often hear are U-value and thermal efficiency.
Put simply, the U-value measures how much heat passes through a material. The lower the U-value, the better the material is at preventing heat from escaping. For doors, this means that a product with a low U-value will do a much better job of keeping the warmth inside during winter and the heat out during summer.
Thermal efficiency is the overall measure of how well a door performs at reducing heat transfer. A highly efficient front door creates a barrier that helps maintain a comfortable temperature indoors without your heating system working overtime.
By choosing a door with a strong thermal performance, you’re not only improving comfort in your home but also reducing the amount of energy you need to use, and that translates directly into savings on your bills.
Understanding U-values and energy ratings isn’t just about numbers; it’s about the real difference they make to your home and your wallet. A front door with a low U-value helps keep more heat inside, meaning your heating system doesn’t have to work as hard. Over time, this can lead to noticeable reductions in your energy bills.
Our manufacturers composite doors are independently tested to deliver excellent thermal performance, meeting and often exceeding industry standards.
That means when you invest in a door from Fortis, you’re not just choosing strength and security. You’re also choosing a long-term solution that keeps your home warmer, lowers your energy consumption and helps protect you against rising costs year after year.
