A couple of tips from the trenches...
1. The difficulty lies not in the EXTERIOR walls, but in the common walls between placement of rooms. I would suggest including exterior walls in your unit plans.
Demising walls can be placed in your unit plans, but on a SEPARATE STORY. Then, when creating your building plan, you can only link the main story; leaving out the demising walls. Issues arise when Unit A sits next to Unit B, then sits next to Unit C etc. Then Unit A may also be an exterior unit with a whole different wall type at the exterior.
Note that there are VISIBILITY options that will allow you to see the walls from a different story on the main story.
2. I would suggest inlcuding the ZONES as part of the UNIT plan file. Then when changes are made to this unit type, all the appropriate zones in your building plan will update.
It will also allow you to do SINGLE calculations per unit type. So if you just want to know how many lights are in Unit A, you can do that from the unit plan, using its own zone.
In fact, you can start all your UNIT plans as only zones; place into your building plan; then as you develop the REAL unit plan (walls, etc.) your building will grow.
3. As mentioned previously, any MODULE may have its link broken at any time.
Hope this is useful...
Duane
Visual Frontiers
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