A "U Value" is a measurement of how well a building component retains heat inside a building. For warmer countries, this is equally important because the "U Value" is also used to determine how long the inside of a building can be kept cool.
In both cases "U Value" is needed to establish the amount of insulation required to retain a comfortable interior temperature and measure carbon emissions.
So, a "U Value" is a measure of the heat flow through a building element (e.g. Wall) The higher the U value the more heat you are loosing. Therefore the lower the "U Value" the better for us because we want to retain the preferred temperature.
How do we measure a “U Value”? Well, this is where our curious but impressive algebra—the W/m2K comes into its own!
“U Value” describes how much thermal energy, expressed in WATTS (That’s the W) is transported through the building component the size of 1 SQUARE METRE (that’s your M2) at a temperature difference of 1 KELVIN (there is the K). The Kelvin is equal to 1 deg C. So, W/(m2K)
What do we need to achieve in a wall under the English Building Regulations Part L?
The law says a min of) 0.30W/m2K must be achieved.
What do we achieve with our 140mm stud system?
Using basic Rockwool we can easily achieve 0.27 Wm2K
The better the quality of insulation, the lower the U value will be
Depending on the insulation we use we can get down to almost ZERO emission.
We can therefore easily meet and beat minimum requirement, once again demonstrating that we have a very superior 140mm system compared to other systems available
Ours is also an infinitely superior system to Brick/Block construction, as we exceed the target rating and still have a clear cavity for air circulation which Brick & Block do not have, because the cavity in traditional construction is stuffed to the gills with all sorts, to achieve the minimum rating of 0.29 Wm2K. This is an indication that old fashioned non-ecological methods of construction especially using harmful quarry products is yesterdays technology.
The only way to reach lower level values with traditional masonry construction is to widen the cavities to take more insulation as there is nowhere else to put it. Insulated wall-boards can be introduced to the internal block walls but this reduces the room sizes and wider cavities do exactly the same if the extra void has to come out of the room side dimension.