Wednesday, November 2, 2011
When is a discrepancy not really a discrepancy?
They both are confident to be following well established building-documenting practices.
The structural engineer sizes the concrete column; the architect places it in the space. There is a code on the structural drawing that can be tracked to the schedule and the dimensions are noted. The architectural plan neatly sets out the column’s centre point from two nearby, perpendicular grids.
Then comes the eager BIM modeller and screams with joy as she overlays the see-through plans on her digital light-table: A discrepancy! The columns are not aligned on the two images, out by a bit.
She writes an RFI! (or a query with a proprietary, fancy name).
Hate to take the wind out from under her wings, but this technically IS not a discrepancy, let alone clash. Obviously we are dealing with the results of a non-model based documentation and a slightly stroppy CAD work, but viewing the outputs from the creation of the virtual model representation of the building, neither the architect nor the structural engineer have blundered.
You don’t often hear me straightforward release the above mentioned consultants of their responsibilities for less then adequate work, the reason I’m doing it today is to highlight a silly practice that is spreading amongst those that are supposedly are DOING BIM.
The practice of lead-balloon RFI’s.
Sorry, they are waste of time, do not fly.