So, you’ve decided to replace your front door. Obviously you’ll have looked at colours, styles, glass and hardware, but have you looked at how the door performs thermally?
You might think that the subject of U-Values isn’t all that interesting. However, understanding this measurement of thermal performance can help to ensure that you’re getting the best insulation and efficiency for your home. After all, energy is not getting any cheaper.
The design, construction and materials used in composite doors vary from manufacturer to manufacturer and so there are many options available to you the consumer. Finding out the thermal efficiency of the doors you’re interested in could help you in the decision making process.
First things first…. How is the thermal efficiency of a door measured?
This part’s a bit technical but a U-value is calculated by measuring the amount of watts per metre kelvin (a kelvin is the unit of temperature measurement in the physical sciences).
To put this in simple terms, a U-value shows the rate and amount of heat that passes through a door. It is calculated by including the combined thermal resistance of all elements within the door, including the glass, frame, air spaces, gaps and fixings – such as the hinges.
Ultimately, when buying a door what you need to know is that the lower the U-value number the better the thermal performance of the door. And a more thermally efficient door means the less costly energy you lose from your home.
UK Building Regulations
Current building regulations state that all doors including glass and the frame must achieve a U-value of 1.8 W/m² or less to comply.
Solidor with its timber core sits well within this regulation with a maximum U-Value of 1.5 W/m². This rating can be further enhanced by opting to have laminated glass within your door as this additional element increases thermal efficiency as well acting as an enhanced security feature.
So there you have it, U values explained.
Not all doors are created equal, and so remember to ask the question whenever buying a new door.