ADCAS revisits the issue of non-standard duct sizes
In the face of mounting evidence that some system designers are increasingly using non-standard sizes of ductwork, ADCAS (Association of Ductwork Contractors & Allied Services) is renewing its initiative to rationalise the standard sizes of circular ductwork. Philip Johnson of ADCAS says, ‘With BS/EN 1506:2007 now published, the time is right to return to the battle against waste and excess cost. Certain UK designers are still insisting on using ductwork sizes that just don’t exist anywhere else in Europe. We must make them aware of the problems this causes.’ In particular, ADCAS members are expressing growing concern over the return of sizes such as 224 and 280 mm, which were declared non-standard back in 2001. The old 180 and 224 mm sizes are sill being requested for dust and fume removal systems. These sizes, along with 600 mm ducts, were supposed to have been phased out as the result of an ADCAS campaign supported by industry bodies such as BSRIA, CIBSE, HVCA and HEVAC. The campaign will be aimed at everyone in the procurement chain — asking designers not to specify, manufacturers not to make and contractors not to install. Manufacturers of air terminal devices are to be asked not to provide grilles and diffusers to match non-standard sizes. Software houses that provide design programmes for building services are being asked to alert users to non-standard sizing.