Thermal Imaging for BREEAM
Colin Pearson
BREEAM AP BSRIA Head of Building Performance Level 3 Thermographer Chairman of UK Thermography Association
Built environment specialists
BREEAM Requirement
Construction and handover One credit 14. The main contractor accounts for a thermographic survey within the project budget and programme of works. 15. Once construction is complete a thermographic survey of the building fabric is undertaken in accordance with the appropriate standard and by a professional holding a valid Level 2 certificate in thermography (as defined by the UKTA website http://www.ukta.org) 16. The survey confirms: a. Continuity of insulation in accordance with the construction drawings b. Avoidance of excessive thermal bridging c. Avoidance of air leakage paths through the fabric (except through intentional openings) 17. Any defects identified via the post construction inspections are rectified
Built environment specialists
Thermographic survey of building fabric
Survey type
Standards Conditions Inside Outside Qualitative Quantitative
Built environment specialists
Appropriate Standards
BS EN 13187:1999
Thermal performance of buildings. Qualitative detection of thermal irregularities in building envelopes. Infrared method Same as ISO 6781 Currently being updated in 7 parts
Part 1: General Procedures Part 2: Equipment Requirements Part 3: Qualifications of Equipment Operators, Data Analysts and Report Writers Part 4: Categorization of Application Part 5: Conducting Thermographic Inspections and Reporting of Results - Residential Part 6: Conducting Thermographic Inspections and Reporting of Results Commercial Part 7: Conducting Thermographic Inspections and Reporting of Results Institutional
4
Built environment specialists
Conditions for surveys
Temperature difference >10K Heating or cooling in operation Temperature not changing Wind speed <5m/s No solar radiation No rain mist of fog
Built environment specialists
Level 2 certificate
ISO 18436 Part 7 (2008)
Requirements for qualification and assessment of personnel -- Part 7: Thermography
Sets out syllabus, training hours, experience for training and certification of thermographers
Level 1: qualified to work under supervision Level 2: qualified to conduct and report on surveys Level 3: qualified to develop procedures and train
Other Level 2 qualifications are available
Built environment specialists
6
Continuity of insulation
Is the intended insulation present? Is it well fitted? How big are the gaps? Is this acceptable? Should limits be set?
7
Built environment specialists
Thermal Bridging
Is the insulation continuous as required by Building Regulations and are there bridges? Requires judgement Can use Thermal Index, TI Acceptable limits can be set Possible future regulations
Built environment specialists
8
20 19.1 18
Typical wall U Value 0.35 TI 0.95
18.4 15.8
16
14 Temperature, C 12
Cavity
Block Air
Brick Air
2.8 0.2
8 6 4 2 0
Plaster
10
Insulation
3.9
0.0
50
100
150 200 Distance, mm
250
300
9
Built environment specialists
Mortar joint, missing insulation
20 18
U value 1.41, TI 0.82
16.3 14.5
Block
16
14 Temperature, C 12
Air
8 6 4 2 0
Plaster
10
Missing Insulation
- 11.2
6.4
1.5 +
Air
250 300
10
Mortar
Dewpoint of 20C air at 80% rh = 16.5C
Brick
0.0
50
100
150 200 Distance, mm
Built environment specialists
Air leakage
Wind driven Buoyancy driven Pressurisation test Into building Into structure Useful diagnostic tool for airtightness
Built environment specialists
11
Faults rectified
21.4 C
Requires thermal imaging before
A R01
20
18
16
14.4 C
and after rectification And re-evaluation of the complete building
22.0 C 22
20
A R01
18
16
14.5 C
Built environment specialists
12
Find a thermographer
Go to UKTA website Click on map Find thermographer by location Check their qualifications and quality of their work
Built environment specialists
13
Summary
Thermal imaging is a useful QA tool Confirm construction is in accordance with design Reduced carbon emissions, greater user satisfaction and longer building life
Built environment specialists
14
