I could go on for hours about this. We've been using Revit for more than 5 years on at least 5 major preservation projects. In the fewest words possible - here's my appraisal:
1. The old practice of having the "draftsman" prepare base drawings does not work for Revit. We have found many times that the younger staff just do not have enough knowledge of building systems and materials to correctly identify them in the field and then to enter the data in the "model." We had full construction drawings from 1918 and we discovered too late that the the younger staff were not correctly interpreting these drawings.
2. Even after 5 years of use, we still do not have a sound method for when and how to take field measurements, and how and when to enter the data into the "model." We've tried early and middle of the drawings preparation sequence and each has draw backs.
3. We have also tried very detailed conflict analysis - conflicts between the trades. This has some benefits, but it is still no substitute for actual system coordination.
4. So far, I don't believe any client has utilized these Revit models in any way after the construction project is completed. Two of these projects ere for Federal clients.
5. Our younger staff still swear by Revit and claim the "Parametric referencing" outweighs the difficulties. For example, Revit has the ability to create a window schedule based on the data entered for each window in the "model."
6. Although we learn from each successive project, in the preservation world, one never has the same building type twice. Hence, there's very little production drawing carryover between projects. I'm very envious of our colleagues designing new buildings because I think they have the ability to refine designs based on previous similar buildings.
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Baird Smith FAIA
Quinn Evans Architects- DC
Washington DC
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