I am creating my model in OS and I have to make a void(empty hole) between zone A and B. but I do not know how to do it. Thanks in advance for any help!

Image C:ZoneVentilation:WindandStackOpenArea

Image D:ZoneVentilation:DesignFlowRate D:

I am creating my model in OS and I have to make a void(empty hole) between zone A and B. but I do not know how to do it. Thanks in advance for any help!

I am creating my model in OS and I have to make a void(empty hole) between zone A and B. void in my cube but I do not see an option of void in subsurface type. as it is showed in the image below,I would like to know how can I change this door to do it. void? Thanks in advance for any help!

I am creating my model in OS and I have to make a void in my cube but I do not see an option of void in subsurface type. as it is showed in the image below,I would like to know how can I change this door to void? Thanks in advance for any help!

I am creating my model in OS and I have to make a void in my cube but I do not see an option of void in subsurface type. as it is showed in the image below,I would like to know how can I change this door to void? Thanks in advance for any help!