Advanced tab on Model Options dialog.
This is the maximum gap between neighbouring parallel (see Adjacency angular tolerance below) surfaces that will be interpreted as being an adjacency between 2 objects. It is used to determine which elements are adjacent to other spaces and which are adjacent to the exterior. It is also used to decide whether a component block is adjacent to a block surface or not.
Note: By default in cases where a component block is positioned closer to an external wall than this tolerance, windows on the external wall will be removed. If you would like to allow component blocks to be positioned closer to the window than the default tolerance of 0.5m then enter a smaller value here.
This setting applies to all model geometry but is particularly important when importing BIM geometry which often includes gaps between zones. You might enter a value higher than the default 0.5m if the adjacent spaces are separated by very large gaps due to thick partitions or ceiling/floor voids being excluded from any gbXML data imported. For example if the largest gap between spaces that are to be modelled as adjacent is 0.6m then enter 0.6m here.
The Adjacency tolerance can also be set from the Import BIM/gbXML Model dialog before finalising the import.
In order for 2 neighbouring surfaces to create an internal adjacency they should closer to each other than the limit defined for the Adjacency separation tolerance (above) and the angle between them should be no more than this tolerance. The default tolerance is 5°, the minimum is 1° and the maximum is 10°.
Ground and Adiabatic component blocks always have adjacencies with any neighbouring building blocks (when closer than the Adjacency separation tolerance) and so will cause any openings to be lost on shared adjacency surfaces when placed next to walls. By default Standard component blocks do not do this and they can be placed close to (or touching) walls without windows etc being lost. However it is possible to cause Standard component blocks to behave like other component blocks in this respect by checking this option.