ZEMCH 2019 International Conference Proceedings April.2020 | Page 31
3.3 Design compliance discrepencies
An identified defect during the testing was a result of design change with non‐compliant
construction detail. In this investigation, a design change occurred by client’s choice, where a decision
was taken to add fake exterior windows for an aesthetic reason in site 2. The result of these construction
defects could lead to thermal bridging that might compromise the thermal efficiency of the building
envelope as illustrated by thrermographs images in Figure 4. Both thermographs [A] and [B] show
anomalies of surface temperture of the exterior wall externaly and internaly. The discrepancies of
thermal behavior of the exterior wall are a result of non‐insulated concrete fill and the resulting heat
gain through convection of the hot air trapped between the glazing and the non‐insulated infill.(Fig 5).
Design changes during construction with implementation defects may form a large share of heat gain
in itherwise insulated buildings. In spite of the fact that they are common rather than exceptional, their
consequences have been largely ignored in simulations despite their potential significant reduction of
the global thermal resistance of the envelope.
[A]
[B]
Figure 4: Themographs of exterior wall in site 2, non‐compliant design changes [A] exterior face of the wall, and
[B] interior face of the wall.
Figure 5: Construction details, left) Typical wall construction in the case study, right) Heat gain through
convection as a result of thermally incompliant design changes
Thermography Residential Building Defects Detection during Construction in the UAE
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