One of the defining questions in the European construction industry at the moment is how to reduce time on site. This comes from the logic that the quicker a construction program is completed, the higher the profit margins for the contractors and the quicker the customer can get to making money from whatever use the building is being put to.

It applies just as much to the commercial property or hotel owner who wants to rent the space as it does to the supermarket or restaurant owner who wants to sell food from the finished building.

Thus, there are all sorts of techniques and technologies being explored across the construction supply chain to optimize that onsite time — ranging from just-in-time logistics and delivery of materials to site to improvements in the installation itself. Some of the developments have seen techniques that were once considered too expensive or complex or were simply judged as being too far from conventional practice brought back to the drawing board.

When it comes to reducing the store fitout program for supermarkets, the cooling industry is naturally a key area of focus, given the relative labor intensity of the installation of the refrigerant pipework.

It is in this context that the development of "ducted air" refrigerated cabinets has assumed new importance. The simple act of confining the refrigerant pipe to the plant room cuts out an enormous amount of installation time on the shopfloor.

When the additional benefits in maintenance (no drains for instance) and refrigerant use are added in, it is clear that the somewhat more complex initial works and capital expenditure are worth exploring. Then, there are energy benefits claimed, too.

Equally, the installation of AC pipework constitutes a significant element of the building services work in commercial property, so cooling specialists are looking closely at how prefabrication techniques can shave time off the installation program. This naturally requires something of a change of mindset for AC engineers more used to doing all their installation works in situ and in brazing all the pipework themselves.

Manufacturer Toshiba UK recently carried out an installation program for a large hotel chain in England that saw entire room modules prefabricated in China, complete with the VRF system and pipework, then shipped to the UK. The systems are connected to the outdoor units onsite in the UK, and the whole system then commissioned in situ.

The project required significant liaison between the UK installers and the Chinese factory to ensure the designs were accurately conveyed, but the program time was able to be reduced significantly. The biggest element was naturally the ability to deliver much of the building services on day one of the program, but further time could be saved thanks to less work at height than normally required with AC systems and the preassured quality of factory-assembled components.

But perhaps the most significant potential change to site culture comes in the rapid growth of so-called "braze-free" jointing systems for cooling pipework.

In the UK, as in much of Europe, there has long been pride among refrigeration engineers in their ability to braze, both for consistency and quality. Given the importance of keeping the refrigerant in the system, it stands to reason that the skills of brazing have been prioritized in training engineers over the years.

But, say critics, despite great efforts to bring leakage down over the years, the integrity of brazing still depends on an individual accurately completing every single joint. As a result, it is generally held that 2 percent of all brazed joints fail.

Over the years there have been various efforts to improve upon the consistent quality of joints via a variety of mechanical jointing technologies. The first iterations of these systems were, in retrospect quite complex and as a result quite expensive and as with many new technologies, sometimes suffered high-profile failure, often due to incorrect installation.

But now there has been a definite acceleration of braze-free technology, thanks in no small part to manufacturers co-opting and adapting press-sitting techniques that have been tried and tested in the heating and plumbing sector.

The advantages of consistency, time-saving and relative lack of individual skills required have seen the techniques gain in acceptance to the point where the technology specialists are, without hyperbole, claiming we are on the verge of a revolution.

In fact, one of the pioneers of press-fitting pipework systems for the European heating sector has this week predicted huge potential for the cooling industry.

Mano Bakhtiari, managing director of Conex Bänninger, who developed three-point press fit some 25 years ago, said the ability to produce pipe joints of a consistent quality within 5 seconds would see braze-free jointing making up 50 percent of the cooling sector's new installations within the next five years. It is in the low single-digits now, so that's a huge leap and a huge cultural change among engineers brought up on the brazing torch.

"This is not about 'getting rid of the engineers of today,' this is about giving them additional skills," Bakhtiari says. "Brazing has a failure rate of 2 percent, and at best it is a variable process, whereas press fit takes five seconds and is predictable."

One of the increasingly influential benefits with the new systems is the lack of hot works. Tales of engineers having to apply for a new hot works permit for brazing every morning, then having to do a fire watch for two hours at the end of each day can only raise the status of the "flame-free" systems in the minds of end-users.

Bakhtiari says a veritable "press-fit revolution" with as many as a half-dozen manufacturers now poised to offer different iterations of press-fit systems between now and 2018 has been prompted by improvements in the process

"We have addressed the issues faced by earlier brazeless jointing systems," he says. "We have addressed the failure rate and the cost."

If engineers can indeed be persuade to put down their torches, the typical cooling installation may look different in five years' time.