3.6 Cross Vent Using Single Stack

Ventilation chimneys provide an alternative to venting through corridor walls. When ventilating vertically stacked spaces, it is common to use multiple chimneys, one per floor, such not to acoustically link vertically stacked spaces. This arrangement is disadvantaged by the floor area taken up by the ventilation stacks. Illustrations 9 to 14 overcome this issue by combining multiple vent stacks into one by means of using NAT Vent attenuator

Vent Stack within Separating Walls
The ventilation chimney is located within the separating wall between two cellular spaces 9. Cross talk attenuators are required within each cellular space. The 3D section of the building 10, shows the NAT Vent located in a bulkhead within each cellular space. In this instance, the approximate length of the attenuator is in the order of 1200mm.

NAT Vent Attenuator in Bulk Head
This is a relatively conventional approach where air and sound passes through cross talk attenuators prior to entering the ventilation stack 11. The attenuators are located within a bulk head. The NAT Vent Attenuator depth in this instance will be in the order of 600mm.

NAT Vent Attenuator inside the Ventilation Stack
This is a similar approach to above, although the cross talk attenuator in this instance is located within the Ventilation stack itself 14, resulting in a deeper shaft but no bulk head.