Insulation U Value, R Value and K Value explained

Insulation terms like U Value, R Value and K Value can be a little overwhelming when you start to try and research what is best for your needs.

This is particularly the case when you are not working to set specifications as would be found in a new build project or a major extension or renovation. These terms can seem technical and confusing so our helpful guide will try and make this all a bit more straight forward for you.

What does Insulation U Value mean?

The Insulation U Value (or Thermal Transmittance value) is the rate at which heat is lost through a given thickness of a part of a building such as the wall, roof or floor.

You want the U Value of any material to be low and ideally any material to gain a small bit of heat over a given period. The unit of measurement used for this is W/m²K (Watts per square metre – Kelvin).

Although a material will have a U Value, when considering the overall U Value of a building then you must consider the R Value of all materials used.

What does Insulation R value mean?

The Insulation R Value is used to judge how a material can resist heat transfer at any given thickness. Since you are ideally looking for materials that can resist heat transfer effectively you should choose materials that have a high R value. The R Value refers to the material itself and it’s thickness.

What does Insulation K value mean?

The Insulation K Value (or Thermal Conductivity value) is the ability of any given material to conduct heat. Heat energy does not pass as effectively through materials with low thermal conductivity so ordinarily you should be looking for low K values when dealing with insulation.

If you need any assistance in choosing the right type of insulation for your needs just contact us and our friendly team will help in every way needed.