Thermography of Buildings
Stacey Ward
- BSRIA Instrument Solutions - Sales Manager -
1
Benefits of thermography
 Quick inspection
 Results clearly shown in pictures
 Shows precise location of fault
 Shows severity of fault
 Shows compliance with
regulations
 Improves build quality
2
Limitations
 Needs temperature difference
 Needs clear view of surface
 Building surveys limited by
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Wind
Rain
Past temperatures
Not an accurate heat loss assessment
 Cameras are not cheap

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They are more affordable than they were
And you can hire by the week
3
Typical applications
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Building insulation and air leakage
Building energy efficiency
Building moisture surveys
Pipework
Electrical installations
4
Building insulation and air leakage
 Meet requirements of Building Regulations
Part L ‘reasonably continuous thermal insulation’
 Show air leakage paths to help re-sealing
5
Air tightness testing
6
 Testing to include
effect of leakage
through the floor
 Can include smoke
testing
 Can include both
pressurisation and
depressurisation
tests
7
Locating air leakage
13.4°C
12
10
S P 01
8
6
4.6°C
8
9
Understand how thermography is affected by:
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features of buildings,
surface properties
acceptable temperatures,
understanding the environment you are
working in,
 obtaining a good image,
 differentiating between anomalies
 faults and normal temperature variations.
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Thermal Imaging
 10oC temperature
difference for at
least 4 hours.
 Dry, no sun, wind
speed < 8m/s.
 320 x 240 pixels
minimum infrared
resolution.
11
Features of buildings important for
Thermography
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Masonry or framed construction
Glass
Rainscreen cladding
Air outlets
Light fittings
Heaters
12
Framed construction - roof
13
Framed Construction - walls
14
Glass not transparent
14.5°C
A R 01: 11.6° C
14
S P 01: 15.8° C
13
12
11
10
10.0°C
15
Heat sources under windows
13.0°C
12
10
8
7.0°C
16
Acceptable temperatures
 Need to have sufficient temperature
difference to detect defects
 Normally means at least 10°C between inside
and out
17
Understand the environment
 Heat exchange by radiation and convection
 Sky can be –50°C
 Sunshine can raise surface temperature to
+70°C in the UK
 Set the ‘ambient temperature’ in your camera
 Wind can eliminate surface temperature
difference in external surveys
18
Effects of cold sky
-3.1°C
-5
S P 01: <-20.0° C
S P 03: -3.9° C
S P 02: -14.1° C
-10
S P 04: <-20.0° C
-15
-18.0°C
19
In buildings with no heating
20
Solar gain can be used to an
advantage
21
Obtain a good image
 At survey time:
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Subject
Distance/resolution
Focus
Broad temperature range
 In analysis
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Correct temperature range
Correct environmental settings
22
Zoom in to focus
13.0°C
12
10
8
7.0°C
23
Zoom out for full image
13.0°C
12
10
8
7.0°C
24
Benefits of high resolution
25
Defect, anomaly
or feature
36.0°C
36
34
32
26
30
30.0°C
Cold bridges - steelwork
26.5°C
26
S P 01
25
24
S P 02
S P 03
23
S P 04
22
21.2°C
27
Thermography locates air leakage
behind plasterboard
28
Thermography locates air leakage
behind plasterboard
31.0°C
31
30
29
28
27
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25.5°C
29
Extract from the
thermographic
report
Note: this is inside of
building but outside was
warmer so the poorly
insulated areas show up
as warm
30
Case study 1
 retail building, 130x75 metres and 6-9 m high
 interface detail left a 73mm strip uninsulated
 =30 square metres of cladding with a U value
of 3.5W/m²K instead of 0.35W/m²K.
 would require an extra 2kW of heating
 nearly 8000 kWh a year extra heating
 cost of over £600 a year
 generating nearly 4000kg of additional CO2.
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Building fabric thermography
 Construction
defects
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Building fabric thermography
 Construction
defects
 Remedial action
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Case study 2
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Traditional brick - cavity - block wall
Note surface temperature variations
Effect of missing cavity bat
Effect of mortar joint
Condensation
Mould growth
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Mortar in poor structure U value 1.41
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Mortar in poor structure U value 1.41
36
Energy surveys
-3.3°C
S P 01
S P 02
S P 03
 Temperature
differences
-5
between
similar areas
 Hidden
-10
features
 Buried
services
-15
-18.2°C
37
Wasted Energy ?
38
Roof Moisture
 Warm area
shows
moisture in roof
structure
39
Roof moisture survey
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Relies on change in temperature
Survey after sunset on a sunny day
Avoid surface water or debris
Moist insulation has high thermal capacity
Stays warm for some time after sunset
Sharp contrast with dry insulation
40
Underfloor heating
 Warm areas
shows
underfloor
heating pipes
41
Underfloor heating
17.0°C
 What can go wrong?
16
21.2°C
20
18
14
16
12
14
10
9.7°C
12.4°C
16.4°C
31.0°C
16
15
30
25
14
20
13
12
11.9°C
15
13.7°C
42
Chilled ceilings
Cold areas are
working, warm
are not
43
Busbars
120.0°C
120
110
S P 01
100
90
S P 02
80
70
65.0°C
44
What to inspect
 Critical items
 Where no other
method
– don’t forget conventional
test & inspection
 Consider failure modes
 Cost / benefit
 Access / safety
45
UPS Battery Systems
46
Electrical thermography to avoid fires
47
A79.3°
RC
01:
68.8°
CC
01:
44.6°
C
AAARR
01:
36.9°
A
R
01:
13.1°
AA
RA
R
AR
01:
01:
R
01:
61.0°
54.0°
81.7°
C
C
C
R
01:
26.2°
C
RA
01:
C
01: 72.8° C
74.0°C
Commissioning lighting panel
60
40
20
12.0°C
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Summary
 Thermography has almost limitless applications
 Quick and easy way of checking quality and
condition
 New regulations will increase use
 Standards are being established
 Training and Certification essential
 BSRIA at the centre of development
49
Thanks! Any questions?
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stacey.ward@bsria.co.uk
www.bis.fm
Anne.king@bsria.co.uk
www.bsria.co.uk
01344 465545
50