Fast track construction

On a ‘traditional’ construction project, the design tends to be completed before a price is sought from contractors. This minimises the client’s risk, as the price can be fixed, and significant variations to the scope or nature of the works should not be necessary. However, this can mean that the project is relatively slow to complete.

On some projects, the client may prioritise time above cost, needing completion of the works as soon as is reasonable. This might be the case for example where there is a fixed deadline (such as the start of a school term), where the client's cash flow is reliant on income generated by the completed project, where there are risks of significant cost changes (on very long projects), where the project is financed by debt, or for emergency works.

Fast-track construction is a scheduling technique that can be used to reduce the overall duration of projects by overlapping tasks that on a traditional contract would not be commenced until the previous task was completed. The greatest time saving is often achieved by overlapping the design and construction phases.

This is possible by progressively freezing the design an element at a time and then constructing completed elements whilst the design of the rest of the development continues. For example, it may be possible to determine a piling layout and begin construction whilst the design of above ground works continues.

Fast-track construction is typically suited to standard building types with repetitive elements and straight-forward construction processes and is most commonly associated with management contracting and construction management forms of contacting. It requires flexibility, co-ordination and co-operation. The project team should be experienced in the technique so that they can envisage how the project will develop and anticipate risks.

It is likely that fast-track construction will be more expensive than a similar traditional contract. Whilst the same number of tasks need to be performed, they are condensed into a shorter period, and so are likely to require more resources. In addition, purchasing costs may be higher due to time pressures, incomplete information and the complexity of managing the interfaces between elements. A greater number of variations are also likely than on a traditional contract.

The risks associated with fast-track construction are also likely to be higher, increasing with the extent to which tasks overlap and the number of tasks that are performed concurrently. In addition, the client will not know the exact cost of the project when they make the decision to proceed, as prices will not have been obtained for all the packages. As a result, they may wish to allocate a higher contingency to the project.

There may be risks associated with beginning construction before statutory approvals have been obtained for the entire design. Design quality can also suffer with fast-tracking as the design process may be compressed, there is no opportunity to revisit decisions, and materials and components may be selected simply for speed.

Early appointment of the contractor is important to allow proper consideration of construction sequencing, packaging of the works, cost estimates, assessment of buildability issues, identification of long lead-time components and for the contractor's knowledge of market conditions.

The project team may be incentivised to control costs, perhaps by a target-cost form of contract, with shared ‘pain and gain’. See target-cost contract for more information. The project team may work more effectively and so potential risks and costs may be reduced by adopting collaborative working practices, for example by co-locating the entire project team, ideally on site.

Fast-track construction should only be considered by experienced clients with experienced project teams. If a single element goes wrong, the entire project sequence can unravel, collaborative working practices can evaporate and the potential for misunderstandings and adversarial behaviour can increase dramatically. Any time that might have been saved can be lost and delays can compound one another.

Fast-track construction should only be attempted where there is a strong justification and where the risks are fully understood.

[edit] Related articles on Designing Buildings Wiki

• Acceleration of construction works.
• BIM.
• Collaborative practices.
• Construction management.
• Contingency.
• Delays on construction projects.
• Design and manage procurement route.
• Force account work.
• Lead times.
• Long lead-time item.
• Management contract.
• Procurement routes.
• Programme consultant.
• Progress of construction works.
• Project programme.
• Project risk.
• Resource leveling.
• Target cost contracts.