What are the energy efficiency ratings of doors?

External doors are one of the main places in your home where you can lose a significant amount of heat. To reduce this, it's important to choose an energy efficient door that's well insulated. This helps to keep your home warm and reduces energy bills. 

The door needs to be hung correctly, and fitted with the appropriate hardware and seals, to ensure it performs at its optimum for energy efficiency. Weather seals can be added all around a door to seal any gaps there might be when it's closed. If the door has any glazing panels it may be that they have different values to the overall door, possibly being a point of extra heat loss. Letter boxes can also be the main point of extra heat loss, but can be fitted with draught excluders to reduce this.

What is energy efficiency?  

Energy efficiency is the measure of how much energy is used compared to how much is lost, and therefore, wasted. The more energy something wastes the poorer its energy efficiency is. The energy efficiency of doors measures how much heat is lost through the door compared to how much heat it prevents escaping. The more insulation a door has, the better its energy efficiency. 

How is the energy efficiency of doors measured?

The energy efficiency of doors, as well as windows and other structural elements, is usually given a U-value or a general energy efficiency rating. These measurements are commonly used in the building and construction industry. You can compare the values given to individual doors to see which will meet building regulations and offer the best insulation.

U-value

A U-value is a measurement for how much heat, in watts, travels through a structural element. It tells us the rate that heat transfers through 1 square metre of a structure depending on the temperature difference between each side, known as thermal transmittance. The lower the U-value the better the insulation properties. External doors should have a U-value of 1.8 or lower.

Energy efficiency rating 

Some manufacturers will provide an overall energy efficiency rating for a door. This shown on a sticker which rates the door from A+-G, this is the same rating shown on modern appliances, such as fridges and washing machines. To meet building regulations in England and Wales a new external door much have an energy efficiency rating of E or above. 

XL Joinery doors all comply fully with current regulations for doors and continually strive to produce the best products they can. All Door set frames, once the separate pre-finished glazed or panelled doors have been ordered with it, will come as a complete doorset, with all weather seals already fitted. Wonkee Donkee XL joinery is proud to be official stockists of XL Joinery and support their aim for excellence. We can deliver across the UK to get the best doors delivered straight to you.