Xtratherm launches Y-Value Calculator

Xtratherm has launched a new online tool which will enable architects, energy assessors and designers to take full advantage of good detailing based on the Accredited Details for Construction (ACDs). The Xtratherm Y-Calculator tool is an easy to use calculator to determine the thermal bridging heat loss from non-repeating thermal bridges that must be accounted for in SAP 2009 and SAP 2012.

Technical Marketing Manager Danny Kearney explains further:

“With the changes to the new Part L and the drive towards low energy buildings, insulation performance can no longer be measured in terms of U-values alone. How that insulation joins with other components in the build and at building junctions, is a critical factor in insulation effectiveness, which in SAP it is measured as the Y-value.With the Y-value calculator we offer additional support to the building industry by making it easier to calculate the thermal bridges in a design. Within PART L greater focus is placed on improving good detailing, which – if done effectively – makes a significant difference in obtaining the desired energy ratings.”

The calculator tool is available online from April 2014 and allows users to calculate the Y-value by entering data from existing SAP calculations or directly from drawings by adding the length of each thermal bridge along with the total heat loss area of the building. Adding each junction as per table K1 in SAP, the tool will calculate the total Y-value of the dwelling. The results will show three different options: the default value will be the result if no particular details are used. A second option will show the result when using the Accredited Details, with the third option showing the Xtratherm results based on Xtratherm engineered jointed products being used.

When using Xtratherm PIR insulation in the design, results will show significant improvement, as the extremely efficient insulation material has the added benefit of engineered jointing. A full user guide has also been made available and contains further explanation on how to use the Y-value calculator. It also contains further reading on thermal bridging and details on how using Xtratherm insulation can improve the energy efficiency of a building.

Y-Value Calculator







For more information or to start your calculations, you can find the Y-Value tool here.