Accredited to ISO/IEC
UKAS Accredited Company
Registered in England & Wales No. 527550
Thermography for Roof Surveys
Infrared thermography can be a very effective tool for roof
asset management. Infrared thermography roof surveys are performed
on roofs to quantify the extent of roof moisture (water) that
is inside the roof system. Infrared thermography is not leak
management. No matter how the water got into the substrate,
the purpose of this type of survey is simply to establish
where the water is located.
Extending the life of a roof will save the owner the expense
and aggravation of re-roofing or re-covering. Re-roofing means
that the roof is taken down to the decking and replaced completely.
Re-covering means that the waterproofing layer(s) are removed,
the wet insulation is removed and replaced and a new waterproofing
layer is put down. The cost of an infrared roof moisture survey
is tiny in comparison to repair/replace roofs, so knowing
the exact location of the subsurface water is extremely useful
information, since only those areas that are damaged need
to be repaired. This information is used to plan budgets and
when needed, as a bid document for contracting repairs and/or
replacement of the roof.
ROOF MAINTENANCE IN GENERAL
The ravages environmental conditions such as sun, wind, rain,
snow, chemicals, leakage, rapid changes in temperature and
time - will eventually cause every roof to fail. Some roofs
last 40-50 years if they are well-maintained, however they
may only last 10 years if they are left and not checked.
Owners may believe that a roof warranty will somehow protect
them from having to do maintenance. Not so, as roof warranties
are written by roofing manufacturers for the purpose of protecting
themselves from liability. For example, often a warranty is
written so that if improperly installed or defective roofing
materials are used on a roof and water leaks into the electrical
switchgear room causing an explosion, the roofing manufacturer
will replace the materials, the roofer will reinstall the
materials, but the building owner has to pay for the replacement
of the switchgear and any downtime that resulted from the
Also, the roofer’s and roofing manufacturer’s
liability, in the case of roof failures are also reduced by
vaguely written roof warranties, which do not define words
like "regular" or "routine" maintenance.
Not accepting the roof warranty is not the answer, since the
roof will not be installed unless the owner agrees to the
warranty. To eliminate these problems, the building owner
should have an agreement with a qualified roofer or roof consultant
to inspect and maintain the roof (in accordance with the terms
of the warranty) at least once a year.
Roof problems usually manifest themselves in two ways: Leakage
and entrained moisture contamination. Leakage is pretty simple,
although the leak inside the building rarely directly relates
to the exact spot on the roof, since the water flows down
the slope of the roof to a spot that is not sealed and into
the building at that point.
Most leaks occur where the waterproofing is sealed or where
there is a penetration of the roof. Since most types of roof
systems absorb some amount of water, it is harder to find
the exact spot of water contamination in the insulation because
it may not leak into the building until it has absorbed all
the water it can hold.
BASICS OF INFRARED ROOF MOISTURE SURVEYS
Some roofs and insulation types or combinations do not absorb
any water. These roofs leak straight into the building. Even
roofs which have insulation types that do absorb water, some
do not exhibit a good infrared signal, primarily for two reasons.
• The surface is too reflective
• The roof’s ballast is so thick (or dense), that
daylight radiation is not absorbed into the substrate (insulation),
therefore it cannot be emitted back into the atmosphere at
Even with a strong infrared signal, factors on the roof can
affect the analysis and interpretation of the data. Some of
these factors: water between multiple layers, old patches,
heavy flood coats, reflective coatings, heat-producing equipment
under the roof –or heat blowing down onto the roof,
stains, ponding water on the roof, heavy build-up of ballast
at parapet walls and along edges.
WALK-ON INFRARED ROOF SURVEYING
To perform a walk-on or on-roof survey properly an experienced
infrared thermographer and an experienced roof consultant
or roofer and the building owners' representative for access
and security should be present. The crew walks around the
roof/s and when an area of suspect moisture is found, the
roof consultant verifies it is wet and then the helper marks
the edges of the area directly on the roof with marking paint
as instructed by the thermographer.
The crew needs authorization and access to
all areas and levels of the roof/s from either ladders or
roof hatches and plenty of time to collect data. The infrared
images are stored on videotape or digital media and printed.
After these have been dispersed to the relevant people the
remedial works can take place.
Figure1: Infrared Image of a Roof survey
Roofs are often replaced because know one knows where exactly
the roof is damaged until it is too late. If you want your
roof to last, it must be regularly maintained by professionals.
Infrared thermography roof moisture surveying is the best
method of non-destructive testing on roofs.
Please download our thermography maintenance check-sheet,
please fill this in and e-mail it back and we can set up a
maintenance schedule to suit your requirements.
Why Infrared Thermal Imaging Surveys
In summary its main benefits are:
• Quick inspection.
• Results easily shown in pictures.
• Shows location of air leakage.
• Shows thermal insulation defects.
• We use the latest detection equipment with fully trained
personnel to achieve reliable results in the most demanding
We carry out many surveys each year and guarantee to offer
a professional, reliable, and helpful and offer competitive
pricing. We offer a last minute service at no extra cost,
and we also undertake weekend Infrared thermography surveys
on both on Saturday and Sunday in order to meet your out of
hour’s survey requirements.
We offer a nationwide service offering a single supplier for
all of your regional offices and projects.
Most of our clients, who use us for the first time, continue
to use our services because of our proactive approach, this
has led to nationwide agreements with many the top UK Companies,
which allows them to benefit from even more competitive rates
as well as unrivalled service.
We also offer other specialist testing and reporting,
• Air leakage Testing to Dwellings and Commercial Buildings
• Fire Enclosure Testing
• Sound Testing
• Energy Performance certificates, EPC, SAP & SBEM
APT Thermography - Further Information
If you have any questions or queries please don’t hesitate
to contact us:
By Mobile - 07967 233836 (available 7am to
By E-mail - firstname.lastname@example.org