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Satisfaction of Clash Detection

Yes, clash detection is a low hanging fruit. Anyone with all trades modeled and a license to NavisWorks can do it. But here’s the thing about it – it’s really really satisfying.
We just finished “clashing” design-intent systems for the Crate&Barrel project. The process is straightforward (although a bit tedious): Clash, Review, Discuss, Report, Resolve, Recheck Clashing is the easy part. Select the disciplines and click go.
Reviewing is one of the most time consuming steps; the VC modeler found hundreds of clashes in each batch, so had to review each, clean-up the view to actually see the clash, locate the clash in comprehensible terms (Level 2; Grids Y & 8A versus Navis’ x/y/z: 345.7, 10.2, 627.4), and then determine is the issue is legitimate (i.e. is it a supply pipe running through the cavity of a wall or a sanitary pipe running through a piece of duct work?). Many clashes are also reported several times, so those are grouped (by renaming them). We also like to group clashes based on location). This generally whittles clashes down from 200 to 20.
The team (including PM & super) discuss the actual clashes, so they can recommend the solution they would like to see. Since this is design-intent coordination, we don’t actually have subcontractors on board – if we did, they would definitely be part of the discussion.
The other time consuming part of this is reporting. The VC modeler put together DCRs, and then sent those to the design team for review. Since the design team is still hosting the model, they will take care of the ‘resolve’ part.
After they’ve resolved the issues, they send us an updated model, so that the VC modeler can do a quick ‘reclash’ and make sure that all issues were resolved, and that no new issues have come up.
Sometimes is nice to work on something linear, with a well-established process and a clear deliverable.

We just finished “clashing” design-intent systems for the Crate&Barrel project. The process is straightforward (although a bit tedious): Clash, Review, Discuss, Report, Resolve, Recheck

Clashing is the easy part. Select the disciplines and click go.
Reviewing is one of the most time consuming steps; the VC modeler found hundreds of clashes in each batch, so had to review each, clean-up the view to actually see the clash, locate the clash in comprehendible terms (Level 2; Grids Y & 8A versus Navis’ x/y/z: 345.7, 10.2, 627.4), and then determine is the issue is legitimate (i.e. is it a supply pipe running through the cavity of a wall or a sanitary pipe running through a piece of duct work?). Many clashes are also reported several times, so those are grouped (by renaming them). We also like to group clashes based on location). This generally whittles clashes down from 200 to 20.
The team (including PM & super) discuss the actual clashes, so they can recommend the solution they would like to see. Since this is design-intent coordination, we don’t actually have subcontractors on board – if we did, they would definitely be part of the discussion.
The other time consuming part of this is reporting. The VC modeler put together DCRs, and then sent those to the design team for review. Since the design team is still hosting the model, they will take care of the ‘resolve’ part.


















After they’ve resolved the issues, they send us an updated model, so that the VC modeler can do a quick ‘reclash’ and make sure that all issues were resolved, and that no new issues have come up.


Sometimes is nice to work on something linear, with a well-established process and a clear deliverable.

2 comments:

Steve said...

In the case where subcontractors are submitting coordination models, if the GC is providing a documented direction to resolve various clashes (DCR's), is the GC potentially taking on unnecessary liability should the direction cause 'unforeseen' problems with a system's operation? (ie. duct/acoustics, mechanical pipe/efficiency)

Campbell said...

Coordination with the trades does not add additional liability to the GC. It would be much worse to let the sub work on his own in a vacuum. All trade contractors owe coordination documents and must participate in the coordination process, which is normally run by the GC or CM.

Secondly most owners buy a designed system from their designers which is supposed to work. Coordination rarely if ever interferes with design intent, only routing.