Our project team would like to clarify if the design of our building meets the natural ventilation requirement of ASHRAE Standard 62.1-2004. The project is a large factory building with the majority of the space not mechanically ventilated. The naturally ventilated space is 64,700 sq meters of floor space. The highest point in this space is the peak of the roof and it is at least 9.7 meters from floor to the bottom of the beams. There is a row of single story offices which are mechanically ventilated in the middle of this space but the area above and around the offices does not block or divide the ventilated space with any full height walls. The walls around the perimeter of the naturally ventilated space have operable louvers and the roof has large area of central roof ridge vents. The total opening area of the louvers and the roof vents is 5,673 sq meters, which is 8.8% of the net occupiable floor area. The ventilated space is a contiguous space and all of the openings are on the roof and walls, but some indoor space is not within 25 feet of any opening. The natural ventilation design of wall louvers and roof vent has got the approval from "Local Zoning Authorities" and "Occupational Safety and Hygiene Management Department" Does this constitute naturally ventilated space which complies with the requirement of ASHRAE 62.1?
The applicant is asking if the project\'s natural ventilation design which has been approved by "Local Zoning Authorities" meets the requirements of ASHRAE 62.1 or equivalent. Per a previous CIR dated 12/11/2008, there is an exception to paragraph 5.1 of ASHRAE 62 that states that an engineered natural ventilation system approved by the authority having jurisdiction (AHJ) over the project does not have to meet the requirements of 5.1.1 and 5.1.2. Approval by the AHJ is sufficient to meet the intent of this prerequisite provided the AHJ approval indicates that the engineered system is sufficient to meet the intent of ASHRAE 62.1, as opposed to local code requirements. Applicable Internationally.