In the building business, construction scheduling is crucial to a successful operation. The notion of building cost is of course essential to the Client. However the overall length of construction time for his project can also be a decisive factor in his choice of a contractor.

Michel Gambassi, Quality manager for GSE, describes the methods which have been defined, time-tested and proven. Application of the GSE methods saves time. 

In a construction project for building large surface areas, does the timesaving notion apply solely to the construction site phase?

M.G. : Quite the contrary. Starting with the very design phase, special expertise must be applied to optimise the entire set of operations. Clear understanding of the client’s requirements, choice of appropriate land, financing conditions, and total control over the administrative authorisations are all factors which can save or waste time. They contribute to either speeding up the project or delaying it unnecessarily. Thus, shorter deadlines do not only arise from the actual construction phase. The upstream phases – from defining requirements in the design phase through to effective signature of the contract and construction start-up – can actually take up to twice the amount of time required to actually build the building. This being said, there is room for improvement that needs to be implemented to optimise the construction timetable.

What are these improvements?

M.G. : One direction for timesavings is to better use the time required to prepare the construction site. Taking one additional month for this phase is never a month lost.

A second axis for improvement, which is a direct consequence of the first, is that, to work well and fast, it is often advantageous to select the option of prefab materials. This can avoid later contingencies on the work site. There are of course prefab solutions for concrete, but there are also prefab solutions for the technical works packages. One example is the “jardin technique “ or technical grounds, a prefab unit created for the Optima warehouses designed by GSE which includes the sprinkler fire protection system technical zones.

Thirdly, although each one of our construction sites is unique, the notion of repeatability does come up in daily tasks. Repeatability, for example in the assembly of prefab parts for certain parts of the structure, is a guarantee of safety, quality, and of course time-savings.

Speaking of efficiency, how would you define an efficient construction site?

M.G. : An efficient construction site is a site where there is a good rhythm, where the pace of work is sustained, where the sequencing of tasks is clear and obvious, without the unproductive risk of overlap, where no one zone remains inactive without a very good reason, where progression is identical from one floor to the other, from one cell to the next. A well-piloted, efficient construction site is one on which every project partner makes money.

So you agree with the old saying that “Time is money»?

M.G. : Construction is no exception to this golden rule. As a General Contractor, GSE manages the work by all the sub-contractors on the project. GSE is thus doubly responsible for delivering the building at the pre-defined date. First, with respect to our client, with whom we have undertaken a contractual guarantee. And secondly, with respect to our suppliers, who are available over a given period of time. The supplier satisfaction survey which we conducted in July 2007 delivered a very clear message. After analysis of the responses to this survey, GSE clearly saw their obligation to set up simple, efficient scheduling tools for their partners.

What tools does GSE have today to organise good operations scheduling on a construction site?

M.G. : The classic bar of GANTT timetable, which shows the work period for each trade on the timetable, remains a reliable tool. However we are currently testing other types of models such as the “the drawing scheduling tool” which is integrated in the "Race" process (Race = rapid accelerated construction expertise) a new approach to scheduling currently being developed by GSE.

Can you tell us about it?

M.G. : For certain structures such as logistics buildings, it is possible to portray a 20 to 30,000-m² warehouse with all the peripheral developments on an A3-format drawing. Through a logical breakdown of the work zones, and using different colours, it is possible, week-by-week, to define the task-sequencing cycles. This facilitates good interactions between all parties and ensures the fluidity of the construction site operations.

Let me explain:

• each colour corresponds to a week of work (W1, W2, W3, W4…);
• for each task (ex.: slabs), the drawing is broken down into zones to which colours are assigned (ex.: cell 1 = W2, cell 2 = W4…) indicating the periods where the work must be done in that part of the building ; 
• with a bar schedule, the work is broken down into tasks such as cladding, roofing, walls , etc…
• in a drawing schedule, work is broken down by zone, or by cell for example. This makes things simple on the work site. With the A3 drawing in hand, it is simple to check the progress status and verify that the progress in a given part of the building complies with the constructional planning.

How does the supply chain perceive this emphasis on time optimisation?

M.G. : It is now accepted that when all the conditions are met, a 20,000-m² logistics building can be built in 12 to 14 weeks, depending on the European country in which it is located, not counting bad weather contingencies, and once the platform is in place and is ready to receive the foundations.

A tight but realistic time schedule means you have to get it right the first time. This implies emphasis on quality,  excellent upstream project preparation, and a commitment from the entire supply chain. Our job as General Contractor is to make sure all that happens.

These are performances we have already been able to achieve, and the bottom line is that it pays off for the entire supply chain.