DXF Import issues - Auto defining rooms

 Product(s):Hevacomp Mechanical Design
 Version(s):V8i (N/A)


Design Database hosts a useful and powerful feature to help you define your rooms automatically. To use this feature productively you need to ensure that your DXF file is setup correctly.


When creating your DXF it can help if you leave out any layers that are not required. Hatching to indicate wall construction are not required, for example, nor are external objects such as car park layouts or trees. Once you have a DXF you are happy with, it should be imported into the Design Database floor you are considering.

When the floor opens, go to the Layers menu option and define the layers for your drawing by selecting the radio button for your layer type and choosing appropriate layers from the list provided. You can even use this utility to remove layers from the floor. 

Push the tick button when you are happy with your selection. You will note that your DXF drawing now has colours indicating the different layer types. Rooms can now be defined.

 An incorrectly defined space can cause the Auto define feature to fail. In any instance where a room space is not fully enclosed, the program can either trace into other spaces which may combine more than one area into a single room, or if an area opens into the world space, the program would not be able to resolve the space, leading to a warning and an undefined room.

If we examine our test DXF, the highlighted rooms will all Auto define correctly. The spaces are completely self contained - Walls and partitions will be created and windows will be added accordingly:

The rooms highlighted in the image below will all cause problems.

Room 1 (green) is open to other room spaces (Room 3 and 4) - this alone would cause these rooms to be included in Room 1's definition, however there are further problems with the area opening out into the world space.

Room 2 (cyan) is open to other room spaces (Room 1) - if this was the only opening, this would cause Room 2 and Room 1 to be defined as one room space. However as Room 1 is open to Room 4 and also the world space, this will cause the definition to fail.

Rooms 3 and 4 (pink and blue) both open onto room 1, and this continues into world space.

Room 5 is a special case and one that should be considered carefully. If you examine this in close up:

You can see the partition indicated abuts the external surface, but does not intercept it. During the Auto define routine this would be considered a gap, allowing the routine to trace into other spaces.

If the Auto define function fails for a particular space then it is likely to be because of one of the items above. Under those circumstance you can either adjust your DXF drawing to consider these issue, and then re-import it, or use the "Trace Room" option to manually define the room.