Often Autodesk® Revit® tools lead to processes that seem like a great idea, and then suddenly turn to a dead end or a bad outcome. Having ascertained a good chunk of the program’s shortcomings through experience and implemented workarounds, this article will identify common Revit fail points for MEP and explain why things aren’t as they seem by showing how to do it better. By breaking down workflows and exploring alternatives, one can expose opportunities to use Revit tools and families to gain better results.
So why does Revit fail? Users often ask Revit to do something it wasn’t made to do. This commonly happens when firms are new to Revit and want to apply old processes to the new tool, make it conform to classic symbology, or are just reluctant to fully commit. It’s probably not the most politically correct analogy, but switching to Revit is very much like starting to a new relationship. The last thing someone should do in a new relationship is bring up what was great about the last person they were in a relationship with. Yet, it is quite common to hear how great AutoCAD is from new Revit users. The lesson is, when trying something new, give it a real chance. Don’t stop a trip through the woods because a tree is in the way.
Above all, try and keep expectations in line with reality. Know that “BIM-Perfect” is a goal and “BIM Good Enough” might be where everyone starts.
When it comes to Revit fails, without question the number one complaint is speed. There seems to be a millions things that will affect the speed of Revit. In the absence of unlimited funds for the world’s greatest computers and network, I offer the following 16 tidbits to help move the needle from turtle to rabbit.
- Work in wireframe, not hidden mode. Use a view template to set all views back to hidden before plotting, or simply have working views and plotting views already in the template.
- Open only the required worksets you need on open. There is a tiny down arrow next to the open button in Revit that allows users to choose which worksets to open. Unopened worksets don’t load into memory, saving computing power for model navigation.
- Reload latest before you sync. This reduces the sync time by loading the changes to the central before pushing the user’s change up to the central model.
- Purge the stuffing out of any linked Revit files. A linked architectural model can potentially have hundreds of views, schedules, and sheets that are not required for the MEP model. Purging them won’t diminish the usefulness of the architectural model, but it will make it a ton smaller, and the MEP model faster.
- Compact your Revit files once a week or more. Revit files puff up with all kinds of information. Compacting does just what one might think, having the effect one would expect.
- If there are a lot of users accessing the central model at the same time, use the Worksharing tool or scheduled times for syncing and printing to prevent database collisions.
- The slowest machine accessing the central brings the whole lot down. All other users must wait while a slow machine takes the time it must to sync to the central model.
- Keep open views to a minimum. Just click Close Hidden every five minutes or so. Every view that is opened must be updated as the model is changed. Close the views to stop the madness.
- Don't make or use over-modeled families. Adding detail that doesn’t add value only adds weight to the model.
- Have only a generic drafting view open during saves and syncs, for the same reason as number 8 above. There is not much to access and update in a generic start-up view.
- Check and clear warnings. Revit likes it when it doesn’t have to process warnings, and so will the user.
- Keep complex sketch-based items to a minimum. When in sketch mode, keep the arcs and angles to a minimum.
- Break your model into smaller models and link. If the model is too big, consider breaking it up into smaller models such as east and west wings, or level one and level two.
- Restart Revit every four hours. Like all of us, Revit likes a lunch break. Completely shut down Revit to clear it from memory in the middle of the day. It will make the end of the day much nicer.
- Work in dependent views instead of the overall view. Dependant views are usually smaller, ergo, faster.
- Detach from central before printing. If only printing is required, detaching from central first will allow the user to print quicker by avoiding the traffic in the central model. It also allows users of the central model to work faster without the constant printing traffic.
Coming in a close second to speed fails are visibility fails. For new users, having something show up wrong, not be there, or be there when it shouldn’t be there is common. Visibility in Revit can get so complex, it spurred a game amongst Revit users called “Where’s my chair?”. A chair is hidden in a model and users compete to find the chair first. When an element refuses to show itself, use the Reveal Hidden Elements tool in a 3D view, select everything, then use the filter tool to isolate just the category of item you are looking for. Chances are, it will reveal itself.
Pipe Breaks Plumbing Fixture
When the plumbing fixtures are coming from a linked background, they can be broken by pipes or other MEP elements passing over. To correct the problem, set the linked background to underlay.
MEP Annotation Symbols versus 3D Architectural Families
Linked models can also wreak havoc with annotation symbols in the MEP model. In this case a wall mounted junction box symbol is losing the battle with a sink underneath. To fix this issue, set the object’s transparency to 100.
Pipe Fittings Are Ginormous
When drawing pipe in single line, fittings can sometimes be completely out of scale. To bring things back in line, go to mechanical settings and check the “Use Annot. Scale for Single Line Fittings” checkbox, verify a respectable “Pipe Fitting Annotation Size,” then set the “Pipe Rise / Drop Annotation Size” to something more appropriate.
Gaps Between Pipes and Pipe Fittings
Fittings can also have some weird affects on their connected pipes such as strange gaps in the pipe.
Unchecking the Use Annotation Scale box in the fittings instance properties usually fixes this issue. A quick way to get all similar fittings is to right-click and select all instances to change them all at once.
Sloped Ceilings and Annotation Symbols
Ceiling hosted families don’t work on a sloped ceiling. If there is an annotation, it will not show up because it is not parallel with the view plane. The 3D component will not look shortened on a sloped ceiling. There are ways of dealing with Revit’s limitations.
- Fixtures can be inserted on a work plane that is parallel to the floor. The plan symbol will be correct, but the 3D representations will be wrong.
- A family can be created with the symbology in a generic annotation family inserted into a face-based family then nested into a new face-based family with the 3D representation. A reference plane with a slope parameter can be used to control the slope of the annotation family within the host family.
Variations of this technique can be used for fixtures that use symbols that are not drawn to scale. Examples are occupancy sensors, fixtures that use symbols that are drawn to scale and are symmetrical such as can lights, and fixtures that use symbols that are drawn to scale and are asymmetrical such as 2x4 light fixtures.
Hierarchy of Revit Graphics
There are so many ways to change the way things look or if they are even displayed in Revit. This little code cracker tells what trumps what. It’s a great way to systematically check through what might be causing the issue. The higher numbers trump the lower numbers.
- Object Styles
- View Range
- Visibility Graphics Overrides
- Phasing Graphics Overrides
- View Depth (Beyond)
- View Filters (Filters nearer the top of the list override filters nearer the bottom)
- Override Graphics in View by Element
- View Detail Level
- View Discipline
- Line Work Tool
- Hide in View
“Element is too small on screen” is one of the most frustrating errors ever. Sooner or later users will want to draw something that Revit just won’t recognize. This stems from the fact that Revit has a setting for the smallest unit of measure and it will not create something smaller than that. That being said, some things might get a user beyond that error.
- Zoom in and try again
- Change unit precision to 1/256”
- Draw bigger, then scale down
If none of that works, it’s time to draw something different.
Linked architectural title blocks can be dependent on their shared parameters, not yours. If the architect doesn’t want to share parameters, users can create a set of “dummy” parameters that can substitute for any architect’s title block parameter.
- Create a set of generic shared parameters to replace any architect’s parameters.
- Make sure the new shared parameter is a project parameter associated with sheets in the template or starter project.
- Replace the label in the architectural title block family to use one of the generic parameters.
Far Out! Revit Section Fail
Most every time a section is drawn, Revit attempts to help out by setting the depth of the section to include the farthest reaches of the model. This leaves users with constantly reigning in every new section drawn. A quick way to deal with far out sections is to simply input a respectable Far Clip Offset in the properties dialog with the section is created.
These tips should help users overcome some of the most common “failures” of using Revit for MEP.
There is no doubt that many more failures await Revit users. That’s life, and is not confined to users of Revit. The secret to conquering failures is simple determination. Don’t give up when Revit challenges you. Revit has been around for a good long time now. Any problem encountered has probably been lived by someone else and solved. It shouldn’t take too much research to find a solution to get back on track. AUGI has brought you these answers, and there are many more stored online. I encourage everyone to search AUGI first and to consider upgrading to a Premier or Professional level membership.