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requirements and their implementa-
tion; the low levels of skill, training,
and investment throughout much
of the industry and its workforce;
and the difficulty of protecting in-
novations and appropriating their
financial returns.
Government aims to use IBTs to
construct 60% of new social infra-
structure projects by 2017. One of
the NHBRC projects is to develop a
dynamic IBT database. This database
will assist provincial departments
in selecting better quality IBTs from
a performance perspective. This
method does not disregard the need
for other procurement interventions
such as choosing more suitable IBTs
for specific climatic zones (not part of
this study). However, amethod is fol-
lowed to evaluate IBT homes already
built to determine a score on general
performance using a South African
Condition Assessment Tool (SACAT).
As part of descriptive statistics the
study describes the results of how
‘as-built’ IBT homes performand then
compared with the expected results
of theoretical analysis.
A method of determining how ‘as-
built’ IBT homes are performing is to
assess the extent of defects using a
tool that inspectors can use. Defects
are defined as being deficiencies in
design, material, construction or
subsurface. A defect can be either
patent or latent. Patent defects can
be clearly recognised during inspec-
tion, the construction period of the
project’s defects liability period.
Latent defects appear over time,
usually once the building has been
occupied. Building defects can be a
result of design errors by profession-
als, a manufacturing flaw, defective
materials, improper use of instal-
lation of materials, not conforming
to the design by the contractor, or a
combination.
Methodology and data
collection
A condition assessment tool for small
and large scale housing projects was
developed to objectively assess the
technical quality of the housing prod-
uct. This was achieved through visual
inspection at the post-construction
phase of a housing project. The scor-
ing was according to critical defects
(symptoms) identified comprising of
the defect importance, intensity and
extent. This assessment will allow
for choosing from those IBT systems
on the ground that qualified (with a
qualifying score) to be placed on an
IBT database. It needs to be high-
lighted that it was not the intention of
the tool to ascertain the exact reason
for the deficiencies for this phase.
With the investigation of the differ-
ent tool types one third of the hous-
ing associations use condition rating
to record the technical status of the
building components. But condition
assessments vary for the hierarchal
classification of building compo-
nents, classified defects and the use
of condition parameters. Several
condition assessment methods lead
to variable condition rating results,
while examining the same defects.
Of interest is a condition assess-
ment tool standardised by the Dutch
Government Building Agency in 2002,
which most building inspectors will
be able to apply in the case of in-
novative building technologies. The
aim was an objective assessment
of the technical quality to provide
property managers with unambigu-
ous reliable information about the
technical status based on assessed
defects. This standard tool was aimed
at property owners, tenants, consul-
tants, contractors and inspectors of
control bodies. Application of the
standard can include the following:
Visualisation; Maintenance planning;
Prioritising of maintenance budgets;
Control of physical conditions; and
Communication about the actual
assessed physical condition and de-
sirable condition.
Condition assessments should be
performed visually by trained inspec-
tors using some small equipment and
measuring tools. An inspector will
pass through the following condition
parameters: importance of defects,
intensity of defects and extent of de-
fect. The extent of the intensity of a
defect combinedwith the importance
of the defect lead to a condition rat-
ing, probably with a defect score.
The main components of the
study’s assessment tool covered the
sub-structure, superstructure, roof,
services and finishes concerned with
health, safety and the environment.
Continued
▶▶▶
ʻA defect can be either
patent or latent. Patent
defects can be clearly
recognised during
inspection, the construction
period of the project’s
defects liability period.’