The WHEN of commissioning

In the third in a series of articles by the Commissioning Specialists Association, we continue to highlight some of the misconceptions about the role of commissioning, by asking four quite simple questions; what, why, when and who. Here we expand on the all-important ‘when’?

First, we need to consider whether commissioning is the same as other aspects of the construction industry, or indeed any other business environment for that matter. The short answer is that, yes, of course it is. The commissioning function is as relevant as it has always been, but the construction industry changes over time and commissioning companies must be ready to adapt to those changes (or to lead them).

An earlier article (Commissioning, the big questions, MBS February 2019) discussed the definition of commissioning. The CSA’s view is that it remains much as it has always been. However, we need to think about the way the function of commissioning changes over time and what determines when it is undertaken? Another key aspect to consider is whether the development of the commissioning management function within main contractors has affected the commissioning industry.

Some would argue it has, but has it also influenced when the mechanical commissioning engineer gets involved in a project. This leads to the further question: What has been the effect on making buildings work as they were designed to? Is it true to say that the commissioning management function now does a lot of the design checking and pre-planning that used to be undertaken by the commissioning team?

Additionally, changes in working practices on site such as no access to electrical circuits; and commissioning by specialists for items like variable speed drives mean that a lot of what used to be done by the commissioning engineer to get systems up and running is now outside of their remit.

Taking these suppositions into consideration, it might well be the case that commissioning companies tend to get involved in projects much later these days. However, it could equally be argued that they need to become involved as early as possible, in order to help ensure that the installation of the mechanical aspects of the systems facilitates commissioning.

There is of course another aspect of timing that needs to be considered by the commissioning world, which has commercial implications. Should commissioning specialists establish a presence on-site as soon as there is a system ready to balance, or should they hold off until there is enough work in order to maintain a degree of continuity once started?

Early engagement means witnessing the development of the project and spotting where the problem areas might arise. On the other hand, unless third-party oversight is factored into the original contract, that approach could mean a degree of wasted time and effort for the commissioning engineer. However much the construction industry changes, time is still money.

As the leading membership organisation in the UK, representing the interests of commissioning engineers, both individually and at company level, for the best part of 30 years, the CSA has first-hand knowledge of these conundrums.

Irrespective of who actually carries out the function, the CSA believes that commissioning should start as soon as the concept design for the building is drawn up. It is at that point (RIBA Stage 2) that that someone needs to start considering how those systems can be commissioned. There are other factors which are driving earlier involvement of commissioning specialists, such as lower flowrates in water systems which create the need for a water quality strategy to be in place earlier in the design process.

Ideally, the mechanical, electrical and plumbing (MEP) design should be reviewed for commissionability at each of the RIBA Design Stages, with the review being in more detail at each stage. Too often, the commissioning aspect can be overlooked. Things like insufficient straight ductwork to get a volume measurement in or insufficient measuring points and regulating valves in a water system often highlight this.

It is true that space for services is always at a premium and components cost money. But that should not prevent at least an attempt to make provision, particularly when the same designers subsequently demand absolute proof of system performance. If that provision isn’t made, the project suddenly finds itself at RIBA stage 5 (Construction) without the wherewithal to prove the design going forward to Stage 6 (Handover).

Admittedly, each review costs money. The CSA does not take a view on the commercial aspects of the construction industry (although our members may well do so). However, a simple breakdown of the cost of a building can be shown as the ration 10:80:10.

These figures show that on average the costs of constructing and owning a building break down as 10% to design and build; 80% to operate it over its lifespan; and 10% to dismantle the building at end of life. The benefits of spending a few extra thousand on top of that first 10% could make significant savings on the next 80%, both in terms of direct energy savings and in terms of making it easier to check system performance during maintenance.

Of course, to take such a long-term view requires that property developers and architects as well as MEP designers to recognise the importance of commissioning. They should also be prepared to invest that little bit of extra money. They might even find it actually saves costs by shortening the time it takes to commission the building, as well as improving its operation and makes long-term maintenance much easier.

Image credit: Shutterstock/Richard Z

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