presentation - Stacey Ward
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Transcript presentation - Stacey Ward
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
Wind
Rain
Past temperatures
Not an accurate heat loss assessment
Cameras are not cheap
They are more affordable than they were
And you can hire by the week
3
Typical applications
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:
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.
10
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
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:
Subject
Distance/resolution
Focus
Broad temperature range
In analysis
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
26
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.
31
Building fabric thermography
Construction
defects
32
Building fabric thermography
Construction
defects
Remedial action
33
Case study 2
Traditional brick - cavity - block wall
Note surface temperature variations
Effect of missing cavity bat
Effect of mortar joint
Condensation
Mould growth
34
Mortar in poor structure U value 1.41
35
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
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
48
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?
[email protected]
www.bis.fm
[email protected]
www.bsria.co.uk
01344 465545
50