Have you ever heard this? The design team is ready to hand over the 98% draft of the pre-draft, and the guy managing the spatial coordination process tells us he has great news for the team. “The design team has already coordinated the Revit models, so we should be able to compress our spatial coordination schedule!” That sounds great, but design team coordinated is not usually up to installation team coordinated standards.
This is in no way intended to be a slam on design engineers and architects. The fact is they have entirely different things to consider. Design teams are professionally liable for an operational system that satisfies all the demands of comfort, health and safety. They create a layout of the system with sizes of duct, pipe and cable that will get the air, water and electricity where it needs to go. The plans and spec book go into great detail on the equipment sizes, horse power and insulation that will keep it all working like they want. So what’s the disconnect? There are some basic considerations for means and methods that don’t always make it into the model, and that is where you run into issues in the field.[tweet_box design=”default”]Here are some things to check as you take a walk through the Navisworks model.[/tweet_box]
So, as the lead for spatial coordination, here are some things to check as you take a walk through the Navisworks model before telling the team the design is “coordinated.”
A 1″ pipe is fairly easy to coordinate. It becomes a bear when you put the 2″ of hard insulation on it. The majority of engineer design models I have received are not insulated, and adding hundreds of 5″ pipes to a layout changes everything. Always coordinate with insulation. Please. Your field guys installing the system will thank you.
[tweet_box design=”default”]A slope pipe can wreck a whole floor of coordination.[/tweet_box]
Sanitation lines can run laterally across ceiling spaces for hundreds of feet. During the course of the run, the pipe elevation can change from bottom of slab to top of ceiling (hopefully not below the ceiling) just due to the slope. What’s the problem? The design model has it nicely tucked in the pocket between steel beams. A slope pipe can wreck a whole floor of coordination.
Spatial coordination in Navisworks and Revit creates a magical environment where everything just “floats” where it is told to be. Real life? You need to hang it from something other than sky hooks. Check the hanger specs, and see if they are in the model. Some of those hangers can be a beast.
Systems below ceiling
Designs may be able to get around elevation issues by tagging the desired elevations, but your field superintendent is not going to let you hang pipe below the door jam (or through the door; definitely seen that). A visual walk through of the model will spot this issue.
Ceilings above bottom of steel
Architects don’t generally clash their systems. I have seen more than one case where the architect wanted an elevation that was higher than the bottom of the steel. Since steel kind of holds up the building, you can guess who wins on that one. Even if the elevation is below steel, it may not be by much. I have worked projects where the structural engineer had to design holes in the steel so we could get the system installed. [tweet_box design=”default”]Check your elevations.[/tweet_box]
Room size vs Actual equipment size
Maybe I’ve worked on anomaly jobs, but I have definitely seen a mechanical room that was not big enough for the mechanical equipment. Engineers can do their homework on equipment dimensions but double check.
So there you go. This list may not cover all possible problems, but if you review the design for these issues, there is a good chance you will get a head start on some critical RFIs and save some serious time in spatial coordination. What do you think? Any to add to my list?