QS develops four-dimensional model to map whole-life costs

Whole-life costs on building projects could be slashed by millions of pounds with the launch of a new cost model developed by property and construction consultancy Bucknall Austin.
QS Brendan Patchell, the brains behind the four-dimensional cost model (4DCM), has found a way to include time - the fourth dimension - into standard three-dimensional construction cost models.
It enables Bucknall Austin to calculate the cost of operating a facility over a period of time alongside the capital cost of building it, making the 4DCM particularly appropriate for PFI schemes and for owner occupiers.
Bucknall Austin has already saved one client an estimated £5m over 25 years through a reduction in gas costs, when the 4DCM identified significant annual operating savings for a relatively small additional upfront capital cost.
Patchell said: "The challenge was to create a single financial model that combined both capital and revenue costs. If we could do this, we would be able to optimise the capital cost budget, while being aware of the impact on long-term replacement, maintenance and operating costs.
"What we've come up with is the 4DCM. It is a fully dynamic model, where all variables can impact on one another. We
can cost different 'what if' scenarios by changing groups of related variables, rather than one at a time, and running the calculations.
"By understanding when costs will be incurred, we can compare short- and long-term options and calculate a project's financial viability by comparing anticipated costs against
projected incomes."
The 4DCM stores around 400 variables in a database to allow analysis of similar projects or options using the same template of logic and pricing. Components are drawn down from a national, structured description library. This gives consistency of approach and enforces the same logic, while allowing a fully customisable report format.
"We believe the advent of the 4DCM will dramatically change the way owner operators approach the construction of new facilities," Patchell said.
"We need a cycle of buildings built using 4DCM to come through to vet our assumptions," he added.