Reaction to news of the latest campaign by the Association of Ductwork Contractors and Allied Services (ADCAS) to rationalise the standard sizes of circular ductwork has been prompt and positive.
Leading companies have been quick to welcome the initiative, which calls on specifiers to stick to the sizing guidelines laid down in BS/EN 1506:2007.
There has been mounting concern over the return to use of sizes such as 224 and 280mm, which were declared non-standard back in 2001. The old 180 and 224mm sizes are also still being requested for dust and fume removal systems.
All of these sizes – along with 600mm ducts – were supposed to be phased out as the result of an earlier ADCAS campaign supported by all the other leading industry bodies including BSRIA, CIBSE, HVCA and HEVAC.
With the new ADCAS campaign under way leading figures in the ductwork industry have highlighted the problems non-standard sizing can create in terms of wasted resources.
“It’s a question of space,” said Lindab’s Joint Managing Director Iain Robertson. “We provide customers with an ex stock service for ductwork and accessories. Non-standard sizes take up warehouse room that should be devoted to standard products. They add unnecessary cost at every level up to and including transport to site.
“We need more support from the consultant and the software houses that provide the design packages for building services. It’s easy enough to set programmes to flag up nonstandard items and offer an alternative. We do it with our own Cad Vent systems. If we can do it, why can’t they?”
Manufacturers of ductwork components share similar views – and problems, as Malcolm Moss, Managing Director of Doby Verrolec explains: “Our range includes Circular Ductwork Jointing Systems. The potential number of non-standard sizes makes it virtually impossible to hold the stock levels we need to provide the highest level of service to our customers.
“Reducing the number of duct sizes would allow us to improve our lead times and reduce our production and stocking costs. These savings could ultimately lead to improved pricing and would also simplify the selection process for the designer. Overall everyone would benefit”.
Ductwork impacts on so many aspects of the system that deviating from Standards can lead to problems for makers of a huge range of components from grilles and diffusers to fire dampers and plenum boxes.
Paul White is Technical Director of Ruskin Air Management Ltd, which includes Actionair and Air Diffusion Divisions: “As damper manufacturers, we are set up to make to order and we can provide any size required in 1mm increments on our standard products. These usually consist of rectangular products with round transitions. However, now that we are venturing into what we define as true circular products, our processes have changed slightly, so each size has a more specific design and parts requirement.
We intend to try and stick with the smaller common EN1506 sizes for these products. In the past we have bowed to commercial pressure and provided some interim sizes and this has involved additional costs.”
ADCAS believes that its new initiative will also bring the UK closer into line with European practice and is in the spirit of the Egan and Latham recommendations.
