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UK Thermography Association
c/o British Institute of Nondestructive Testing
1 Spencer Parade
Northampton NN1 5AA
United Kingdom
Tel: +44 (0)1604 630124
Fax: +44 (0)1604 231489
16.3.8.2 Introduction
Over the last few years the equipment, applications, software, and understanding
connected with thermography have all developed at an astonishing rate. As the
technology has gradually become integrated into mainstream practises, a correspond-
ing demand for application guides, standards and thermography training has arisen.
The UKTA is publishing this technical note in order to establish a consistent approach
to quantifying the results for a ‘Continuity of Thermal Insulation’ examination. It is in-
tended that specifiers should refer to this document as a guide to satisfying the re-
quirement in the Building Regulations, therefore enabling the qualified thermographer
to issue a pass or fail report.
16.3.8.3 Background information
Thermography can detect surface temperature variations as small as 0.1 K and
graphic images can be produced that visibly illustrate the distribution of temperature
on building surfaces.
Variations in the thermal properties of building structures, such as poorly fitted or
missing sections of insulation, cause variations in surface temperature on both sides
of the structure. They are therefore visible to the thermographer. However, many
other factors such as local heat sources, reflections and air leakage can also cause
surface temperature variations.
The professional judgement of the thermographer is usually required to differentiate
between real faults and other sources of temperature variation. Increasingly, thermo-
graphers are asked to justify their assessment of building structures and, in the ab-
sence of adequate guidance, it can be difficult to set definite levels for acceptable or
unacceptable variation in temperature.
The current Standard for thermal iamging of building fabric in the UK is BS EN
13187:1999 (BS EN 13187:1999, Thermal Performance of Buildings—Qualitative de-
tection of thermal properties in building envelopes—Infrared method (ISO 6781:1983
modified). However, this leaves interpretation of the thermal image to the professional
expertise of of the thermographer and provides little guidance on the demarcation
between acceptable and unacceptable variations. Guidance on the appearance of a
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Publ. No. T559382 Rev. a358 – ENGLISH (EN) – June 23, 2009
16 – Introduction to building thermography