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In-situ U-value Measurements

In-situ U-values to ISO 9869-1: 2014 – Heat flow meter method

WMA are delighted to offer In-situ U-Value Measurements carried out using the Heat Flux method to IS EN ISO 9869-1: 2014.

Our specialist non-invasive equipment using heat sensor technology measures the heat flux through an existing structure which is then translated to a U-Value.

These results can be supported by Hygrothermal Analysis to IS EN ISO 15026: 2007 using Wufi with site specific climate data and Thermographic assessments to EN 1387: 1998 to ensure any energy upgrades are risk free and cost effective, more information our hygrothermal risk assessments can be found here.

Taking default values for your heat loss elements is rarely accurate and frequently under-estimates the actual energy performance, with costly consequences to clients and design teams. The graph below illustrates the significant variance that can occur when comparing default U-values, calculated desktop U-values and In-situ U-values, particularly when seeking to achieve a cost-effective energy efficient proposal to achieve your target U-values.

The results can be used to improve the BER rating of your building by using actual measured results rather than the default values!


Comparison of results

The equipment is on site for a week generally so book early if you wish to avail of this service! For information contact us at


Equipment in situ


Thermal imagery