Through our research two processes have been identified as the key sources of error when they are poorly implemented:
• Design Management
• Construction Planning
Key issues in this area and our suggestions are set out below.
A common language to describe error
Our research showed that there is a general lack of coherence about the way we use and understand terms like: error, defect, cause, effect, direct vs indirect costs, tangible vs intangible impacts for example.
This is important because it impedes effective communication and the development of a shared understanding of the issue. This situation is analogous to the position relating to construction Health & Safety
in the 1970s and 1980s before there was a common understanding of terms like risk, hazard, harm, mitigation, and so on.
A common language and understanding around the subject is essential.
In our view, the existence of a common language and understanding around the subject is essential if we are to make progress. As such we propose producing simple models describing the error process and its consequences using construction appropriate vocabulary for adoption across the sector.
In doing this we advocate careful consideration of the terms already in use and proper reference to other sectors like the automotive industry where they have more formalised and developed approaches to the subject of error.
Identifying errors and the costs of error
Our research reveals that, with a few notable exceptions, relatively little is done to identify and record the costs and causes of error in the construction sector.
Where data is collected it tends to relate to defects (ie the outcome of errors) at a contractual handover rather than the causes. The data collected usually relates to the number and type of defects with information about cost limited to the main contractor’s management costs. We found no evidence that designers were systematically collecting data about errors in their work.
As a result there is very little hard data produced about the costs and causes of error in the UK construction industry.
We agree with the saying that “if you can’t measure it you can’t manage it” and as such we believe that suitable measurement techniques need to be developed.
However, we consider it essential to avoid them creation of cumbersome, data heavy and ultimately impractical systems.
We believe that our industry can learn from others gathering data from complex systems. For example, in the public health sector indirect or proxy indicators and simple screening checks are used to understand what is happening and assess the health of an individual or group of individuals.
In our sector we use indirect indicators in relation to Health & Safety when we measure the Accident Frequency Rate.
In effect we measure the number of “injuries causing greater than seven day absences” and draw conclusions about the overall H&S condition of a project or company. This single measure approach is somewhat simplistic by comparison with the approaches used in the public health sector but is useful nonetheless.
We might consider developing a set of easy to obtain proxy indicators that taken together would provide a reliable indication of the type, frequency and cost of error.
For example, the number and type of Non Compliance Reports or defects on completion may be a reasonable indicator of the error rate. Data on NCRs is already routinely captured. Alternatively there may be more incentive to report the number of inspections passed first time.
Similarly, there was a widely held view in our study group that the quality of “housekeeping” on construction sites was a very good indicator of the quality of construction and the error rate.
The Considerate Contractor Scheme provides scores on the quality of housekeeping which may provide proxy indicators of error rate.
There was a view in the study group that features such as contract variations, programme delays, and staff turnover were all correlated with error.
We suggest that work is done to identify suitable indirect indicators of error. This work would involve research looking in detail at error rates on a representative group of projects to establish the most relevant indirect indicators and their relationship to error rates and cost. The indirect indicators could then be adopted more generally across the sector. The data collected would be used by individual organisations, projects or programmes to benchmark their performance and develop improvement strategies. It is recognised that there is at present a degree of nervousness in going down a route that would ultimately lead to organisations being required to publish data of this nature. This is due to fears that the data will be inconsistent and will therefore not be representative of the true picture. Work needs to be done to ensure consistent and correct reporting.
This is not dissimilar to the issues that were first faced when Health & Safety data was published. In the long run if we are to eliminate error it will be important to find a way of publishing error data in a way that is acceptable to the majority.
The nature of the design process
Across the sector there is a surprising lack of a common understanding of the character of the design process.
Specifically, design is an intrinsically iterative process where propositions need to be modified as new information or insights occur.
In the early stages of design the iterations are healthy and welcome in the search for an optimal solution.
Similarly, in the early stages of the design process information is sparse and many assumptions are made.
The design ideas lack detail and design information is coarse. Many contractors fail to understand this fully, believing instead that designers and their clients are indecisive, vague and flaky!
By the construction stage iterations are much less welcome as they can be highly disruptive to the planned construction process and result in delay and increase the chances of error. During construction assumptions are dangerous and detailed information is essential.
Many clients and designers fail to realise this believing instead that the contractors are inflexible, demanding and uninterested in the quality of the outcome!
We believe that it would beneficial to our sector as a whole if all involved were to develop a proper and shared understanding of the real character of the design process. This would make clear that the process is one of refinement where the character of the information produced and levels of certainty are different at different stages of the process.
To this end we suggest the production of a simple but shared model characterising the construction design process which would be adopted in relevant training and educational programmes.
We believe that appropriate investment in the early stages of a project is essential in developing robust proposals which are properly thought through and less likely to need to be changed. It is of course important that money invested in the early stages is well spent and in our experience this is more likely when the Client works closely with the design team.
The lack of a properly co-ordinated design results in clashes on site and consequent rework and delay.
The main reasons for this reported in our study are:
a. The lead designers and/or design managers lack the skill, fee or desire to properly co-ordinate the design;
b. The ambiguity and confusion about who is responsible for design co-ordination in some D&B contracts; and
c. The trade specialists responsible for key parts of the design are not involved in the pre-construction phase and so design co-ordination happens very late in the overall process.
To deal with the first two of these, Clients and Contractors need to identify and appoint suitably qualified lead designers and design managers, make their responsibilities clear and pay them enough to do the job properly.
There was a view among some in our study group that there was a shortage of suitably skilled and experienced people to fulfil these roles. It was suggested by some that formal training of design managers was overly focused on management systems without enough attention being paid to developing knowledge of procurement & construction practice or the effective management of multi-disciplinary teams.
Clients and Contractors need to identify and appoint suitably qualified lead designers and design managers.
As such we recommend that programmes of training for lead designers and design managers be reviewed to assess and where necessary address this deficiency.
The trade specialist input problem appears to be intractable given current procurement rules and practices.
Generally members of the study group agreed with the common view that the use of BIM during design development can facilitate spatial co-ordination and information handling and as such contribute to the reduction of error in construction.
The use of BIM should deliver a total rigorous design process from inception to completion and will be the key to good design delivery. Over time, the mandatory adoption of BIM should lead to better co-ordination of design and eliminate ambiguity about who is responsible for co-ordination.
Our study group identified ineffective planning as the single biggest cause of errors in construction and several of the other causes in the top ten were planning related.
Several organisations identified the shortage of suitably skilled and experienced construction planners as problematic.
Our study group identified ineffective planning as the single biggest cause of errors in construction.
Some identified the mismatch between the stable and predictable environment assumed by many planners and planning systems, and the reality of many fast moving and changing construction projects.
Some advocated “collaborative planning” a technique that comes from the LEAN construction movement. Advocates reported that when properly used it was very effective at improving the quality and certainty of project outcomes.
Some observed that collaborative planning failed to deliver results when, as was often the case, the parties involved in the planning sessions:
• Did not have aligned contractual interests; or
• Were not empowered to make changes to work plans; or
• Did not know enough to be able to assess the impact of changes proposed on other activities.
Others observed that the uptake of LEAN techniques including collaborative planning remains small across the sector and that traditional planning approaches still predominate. These approaches tend to assume relatively small amounts of change during the process and can be cumbersome and inflexible.
A key issue is that although plans are made circumstanceswill certainly change, rendering the plan obsolete. We should not be surprised by this and indeed we need to plan for it. As an industry we tend to forget the plan and just carry on. We need to develop a standard practice for when things change.
In determining how to improve planning skills in the industry we need to consider the following features:
• Simplicity: Simple systems are easily applied and are
most likely to be used successfully.
• Contingency: A plan should make allowance for
• Adaptability: A plan should be continuously reworked
• Resilience: Often it is not possible to immediately
understand the full consequences of change.
Where change is inevitable the system should maximize the team’s ability to quickly assess and respond to emerging requirements.
Sharing Best Practice about error reduction
There could be great benefit if we were better able to identify and share best practice. We see the Professional Institutions, trade organisations and major employers leading in this area.
A few examples that came out of our investigation that would fall into the category of best practice include:
• The use of samples or examples of built work showing clearly the quality level required.
• Safety and Quality inductions on projects.
• Regular Board level reviews of performance in relation to quality and error.
• Regular Director level site inspections focused on quality and error as well as safety.
• Proper consideration of quality and error rates in the selection of contractors