Projects
well . This enabled both WSP and the HVAC subcontractor to accurately indicate queries and issues on the latest drawings , and ensure that these queries and issues were timelessly attended to and closed out . The platform assisted us in generating up-to-date quality reports .
CHALLENGES WITH HVAC EXPOSED LOOK Having the services of the building exposed meant that the coordination between the professional teams was extremely important . Regular design and coordination sessions were held to achieve a favourable outcome . Further challenges were experienced during the construction phase as down-stand beams present on site and not on the model meant that HVAC duct dimensions had to change while ensuring the air velocity and pressure drop were still acceptable .
In certain areas , HVAC ductwork had to be re-routed while still ensuring that the overall aesthetic look was still pleasing . All supply air ductwork as well as the treated fresh air ductwork were internally insulated to prevent condensate from forming on the outer surface of the ductwork . Internal insulation was preferred to over external insulation as the finished product looked more aesthetically pleasing .
IMPORTANT CONSIDERATIONS Designing an exposed HVAC system comes with many challenges , however , if the challenges are overcome the completion of the project is rewarding . The success of the project is hugely governed by an adequate amount of coordination between services and the professional team . It is important to ensure that velocity and pressure drops are within comfortable limits as noise levels are higher when no ceilings are present .
To ensure comfort of the occupants the correct diffusers need to be selected , the building should also be correctly thermally zoned by keeping parameter and internal zones on separate AC units , this enables more accurate control higher level of occupancy comfort . RACA
BACKGROUND Craig Blankers ( Head of Division : Mechanical Services ) and Mohamed Saleh ( Mechanical Engineer ) were both involved in the design , implementation , construction monitoring , commissioning review and close-out of the Heating , Ventilation and Air-Conditioning ( HVAC ) system for the refurbishment of an existing building . While the aforementioned was reviewed by Craig Blankers , Mohamed Saleh spearheaded as the project lead and successfully delivered another office block refurbishment project .
RACA Journal I January 2021 49