BILT Speaker

BILT Speaker
RevitCat - Revit Consultant

Wednesday, 24 November 2021

Revit Mirror Command is So Not BIM

 What is one of the first things that you teach people who are moving from Autocad to Revit?

"When making changes in Revit, DO NOT delete and replace elements - you should always modify the original elements even if it takes longer" 

Why is that?  Because you never know what data or hosted elements are attached to existing elements - so if you "Delete and Replace" you might lose the data or hosted elements.

  • What does the middle initial of BIM stand for?  "Information".
  • Without "Information" you are just working with a 3D Building Model

Revit Mirror Command

Revit is a BIM program, Right?

So you would imagine that it's fundamental command structure would work towards maintaining the BIM concept?

Unfortunately the "Mirror" Command in Revit doesn't follow the BIM rules.

It does not just mirror the selected element(s) - it copies and deletes original, even when Copy is unticked.

  • Select an element
  • Check it's Element ID

  • Mirror the element (with "Copy" unticked)
  • Check the Element ID of the mirrored element
  • Aargh, it is different

So what?  Well, it is just not BIM !

What does this Mean for your model?

Cut elements are no longer cut when mirrored

Joined elements are no longer joined when mirrored


To test this:

  • Create a new family that has "Cut with Voids When Loaded" enabled:

  • Place a solid and void in the family (not intersecting each other)

  • Load the family into a project
  • Place a component where it intersects with another element (in this example, a wall of the same material)
  • Join the component and the other element (wall)
  • Cut the component and the other element (wall)
  • Mirror the component (No copy)
  • Component is no longer joined or cut

Compare to other Revit Commands

  • Undo the mirror command
  • Test the Move and Rotate commands (no copy)
  • Join and Cut are maintained

These commands are BIM compliant - original elements are manipulated

Hosted Elements are Deleted by Mirror Command

  • Add a dimension (or tag) to the component
  • Mirror (no copy) the component
  • If you are lucky you might get a warning about the impending loss of the hosted dimension

What to Do?  Is there a Workaround?

The first thing to do is to contact Autodesk and request that they fix this un-BIM-like behaviour

Despite this problem having existed for over 20 years, it will surely be fixed promptly for you if you ask nicely.

In the meantime . . . . .

There is another way to mirror components in Revit:


Control the Mirror Command

Families can have their own built-in mirror/flip controls.

In the family editor, place a "Control"

  • Reload the family
  • Select the component
  • Check its Element ID

  • Click on the Mirror control
  • The component will flip around its origin point
  • Check the Element ID
  • Woohoo - it is the same! 
  • And the Join and Cut are maintained


Flipping Hosts

Test the flipping control with a hosted element (dimension)

  •  It is not guaranteed to maintain the dimension, but you have a much better chance


Is this going to help you?


  • Obviously it only allows you to flip components one by one.
  • As the flip controls will mirror about the component origin, it may not end up exactly where you need it - but you can then move it

  • It will try to maintain any cutting and joining that you have done
  • It may warn you that joined elements no longer intersect - and you should have the option to unjoin or maintain the join (if the elements will later intersect again)
  • I have not tested the implications for Dynamo - I have no idea if it is possible to access the flip controls within Dynamo.

Revit Ideas Wishlist

There are already a couple of ideas relating to this on the Autodesk Revit Ideas Wishlist

Mirror Not Copy (for mechanical elements but applies to all)

MirrorElement Not Copy API

Wednesday, 13 October 2021

Double-Click Trouble in Revit

In Revit 2019, one of the fantastic new features was the ability to slow double-click to rename views in the Project Browser !  

Fantastic?  Not true - it is an almost universally hated new feature.  If you search on the internet, you will find an endless list of questions and answers on how to disable this feature.

I do know one person (who shall remain nameless) who claims to like this feature - but they are only one amongst thousands (or even millions) who hate it.

Beta Testing

I remember reading about this feature during beta testing of Revit 2019.  Many of the testers pleaded with Autodesk NOT to roll this feature out, as we knew it would cause trouble.  However, it was too late - the code was already in the software.  Autodesk did relent somewhat, and offered us a way to disable it by editing the revit.ini file, to add the line (in the [User Interface] section):


Of all the many online descriptions of how to disable this feature, here is a link to one of them, written by Pieter Schiettecatte on Dan Stine's blog:

BIM Chapters 

Default Setting

Now why did Autodesk make the ridiculous mistake of making the default behaviour different from previous versions?  I would guess that it was to make the change "discoverable" - but it is very annoying that we have to actively disable it.

In contrast to this,  despite much pleading, Autodesk refuses to change one other default behaviour that causes much Revit-misery:

Why, oh why can't they make the "Little Button of Evil" disabled by default?  Yes, that is the "Drag Elements on Selection" setting.

More Double-Click Trouble

Another irritating double-click feature that was added in Revit 2013 was the ability to take you straight into the Family Editor when you try to select a component in Revit.  For various reasons this might register as a double-click - particularly when you try to edit a tag value, for example.  What a huge time-waster that it opens the Family Editor when you clearly do not want to edit the family.

 This was another feature that we asked them not to include after beta testing it - to no avail.

Again, Autodesk relented, but it was not until a couple of releases later (so we had to live with it for a while).

Now you can either edit the Revit.ini file or better still, go to the Revit Options to choose what double-click behaviour you would like.

These settings get saved into your Revit.ini file, so they can be rolled out to an organisation:


I prefer a Double-Click on a component to either do nothing or to 'Edit Type' - but never, ever edit the family.  That should only be done as a very conscious decision of right-clicking or clicking on a command on the Ribbon menu.

Saturday, 25 September 2021

Revit 2022.1 So Good it Trashed the Installer

 Excited by all the hype about Revit 2022.1, I just downloaded and installed it.

All went well apart from a couple of minor glitches:

1 - Parallel Installs

It decided that it could not install more than 33%, and sat there for ages before announcing that it had failed due to some other install going on.  I have no idea what it was - some kind of system update, which required a reboot?

After rebooting the computer the install worked smoothly and quickly

2 - Trash the Installer

After completion, I decided to make a backup of the installer software and remove it from the hard-disk to save space - all 851 Mb of it.

Where the heck was it?  I searched high and low - in the Download folder?  In the Software folder that I had previously moved it to?  No.  

Eventually I found it in the 'Recycle Bin'.  How did it get there?

I may be getting a bit forgetful, but I surely would know if I had somehow deleted the installer?

Could it be that Autodesk have built this "Self-Destruct" capability into the installer?

Or could it be some new trick that Windows 10 performs?


If you want to save time, reboot your computer, and then make a backup of before installing this update.

Now I look forward to testing the new features

Sunday, 15 August 2021

Display Priorities of Solid Fill in Revit Materials

Back in Revit 2012 Autodesk changed the way materials work - so that they had separate graphics and appearance properties.  This was the start of much confusion for many users - and still to this day it catches people out.  You know the drill:  duplicate a material;  change its appearance properties and suddenly a hundred other materials change too . . . .

Well, I am not going to address that issue directly.  Instead I want to look at a more subtle confusion that some users encounter:  Exactly how do the different material properties display in each 'Visual Style' - it will not always be what you might expect or consider to be logical

Material Properties

In order to analyse this issue we start with two very simple material definition examples, applied to two elements in a Revit project:

Material 1 - Demo Generic

  • Light grey shading 
  • Light Blue appearance (different colour to shading)
  • no surface patterns

Material 2 - Demo Green

  • Light green shading and appearance;  
  • no surface patterns

Visual Styles

These materials display as expected in the various 'Visual Styles' in Revit - because we know that the graphic 'Shading' colour property matches the 'Appearance' colour property in material #2 but not in #1 

Material #1 on left,              Material #2 on right

Hidden Line Visual Style

Shaded Visual Style

Consistent Colours Visual Style

The colour displayed for material #1 (left) in Realistic and Ray Trace visual styles is different to shaded and consistent colours because the material properties do not match - this is to be expected.

Realistic Visual Style

Ray trace Visual Style

Material #1 on left,              Material #2 on right


These views are lit with default sun and lighting settings (ie. light source over the right shoulder of the viewer)


Use Render Appearance

One thing that users often forget to address is consistency between the 'Graphics' and 'Appearance' colours.  If the colours are dramatically different, then materials look completely wrong, particularly in 'Shaded' views.

There is a quick and easy way to deal with this - it is the 'Use Render Appearance' checkbox to make sure the shaded colour matches the appearance colour.


This property can be used as a one-off operation - ie, tick the box to change the colour, then untick it.

Or you can just leave it ticked if you want the shading to update when the appearance property might change in the future.

  • NB.  Make sure that the appearance colour is correct first - as there is no 'Undo' so you might lose a shading colour definition.
  • Do not use this method if the shading colour is correct but appearance wrong

Surface Patterns in Materials

When you add surface patterns to materials is where things get more complicated . . .

We will make two more materials, based on the light green shaded material - these will use the same light green 'Appearance' (unchanged).

Material 3 - Demo Green Line Hatching

  • Light green shading 
  • Light green appearance;  
  • Line Cross-Hatching foreground surface pattern

Material 4 - Demo Green Solid Hatching

  • Light green shading 
  • Light green appearance;  
  • Line Solid Fill foreground surface pattern

Visual Styles

Hidden Line

  • Cross-hatch pattern is displayed as you might expect
  • Solid fill displays with solid colour - but without any lighting effects
Material #3 on left,              Material #4 on right

Hidden Line Visual Style


  • Cross-hatch pattern is displayed on top of the shading colour
  • Solid fill displays replaces the shading colour - it is completely obscuredthis can be confusing if the user has not studied the material properties carefully
Shaded Visual Style

Consistent Colours Visual Style

Realistic (and Ray Trace)

  • Cross-hatch pattern are not displayed at all - unless a hatching pattern is defined within the material appearance (not a simple thing to achieve)
  • Appearance Colour replaces the Solid fill colour this is the reverse of what happens in a Shaded visual style - so it can be confusing
Realistic Visual Style

Background Hatching

Just for the record, here is what happens with background hatching - it follows the same rules as Foreground hatching.  [NB. This capability was added in Revit v2019]

Material 5 - Demo Green Line Background Hatching

  • Light green shading 
  • Light green appearance;  
  • No foreground hatching surface pattern
  • Line Cross-Hatching background surface pattern

Material 6 - Demo Green Line Foreground & Solid Background Hatching

  • Light green shading 
  • Light green appearance;  
  • Line Cross-Hatching foreground hatching surface pattern
  • Solid Fill background surface pattern

Visual Styles Materials 5 & 6

Material #5 on left,              Material #6 on right

Hidden Line


Consistent Colours



Solid Fill surface patterns are the one part of this Visual Style issue that cause display inconsistencies.

You may have good reasons for using Solid Fill surface patterns as part of a material definition - in which case go for it.  Otherwise, they are to be used with caution in normal Revit use.

Another approach to avoid the inconsistencies would be to make sure the appearance, shading and solid fill colours all match up.

Don't forget to check how many materials are sharing the Appearance asset before you change it - it is the number above the hand on the Appearance tab.

Wednesday, 14 July 2021

Filtering Filters in Revit

The term "Filter" is much used in Revit - and it means different things in different situations.  Filters also follow varied and confusing rules depending on what you are doing.  Below are some of the rules and exceptions:

Coffee Filters

The 'Filter' icon in Revit probably makes good sense to most Americans, but others around the world might be a bit puzzled - it is a historical image, much like the Floppy Disk for 'Save'.

In the USA, coffee filters are still quite common:

Many American restaurants have a coffee filter machine, with a pot of brown liquid sitting on a hot-plate for hours after it has been dripped through a paper filter.


In Europe you might find various different machines for making coffee - plungers (French Press) used to be quite popular:

In Greece or Turkey, traditional coffee was made in copper pots.  now of course, there are updated electric versions available.

In Australia coffee-plungers are now a rarity, while filters can only be found in antique and junk shops.  Nothing less than a full-on espresso machine will do in even the smallest cafe.  A restaurant with a coffee filter would be laughed out of town:

There ends the 'Filter' icon history lesson.  I have to say that I do like the coffee filter as an icon because it is neat and distinctive - but it might puzzle the younger generation.  I can't see an espresso machine making a good icon.

Jeff has pointed out that the filter icon is probably derived from laboratory funnel filters - probably true, and much more logical than my coffee filter theory!

Selection Filters

When you select a number of elements in Revit, two Selection Filters icons are activated:

Status Bar Filter Icon

The Status Bar icon (lower right of screen) shows the number of selected elements; and the coffee filter icon, which gives you access to the Selection Filter dialog box.


Ribbon Selection Filter Commands

Ribbon Selection Filter commands allow you to:

  • Save, Load or Edit element selections
  • access to the Selection Filter dialog box


This is an invaluable (but underused) tool for filtering down your selection

It is really important to check the selection filter to make sure that you have not accidentally selected partially hidden items (eg. floors, section lines) before you delete, modify or copy them.

View Filters

View filters are created and saved in each project, and can be applied to:

  • individual views
  • multiple views or
  • view templates

View filter rules allow AND and/or OR

  • OR filter capability was added to Revit in v2019, which made our lives so much easier
  • OR filter rules are pure gold (as the French would say)

View filters can be used to:

  • Hide/show elements (Visibility) or 
  • To override their appearance

 Filter Overrides are not part of the View Filter:

  • Overrides are part of the view definition - meaning they are tricky to maintain or duplicate
  • Overrides can be part of a View Template

  • One of the annoying restrictions in View Filters is that Shared Parameters created in loadable Families are not available for use in View filters - unless you also add them as Project Parameters - refer to this blog post

More on View Filters in another blog post . . . .

Schedule Filters

Schedule Filters are quite different to View Filters in many ways:

  • Schedule Filters are an integral part of each schedule - they cannot be separately applied to other similar schedules - this is entirely different and inconsistent to View filters
    • However, Schedule Filters can now be included in View Templates that are then applied to multiple schedules (since v2017).
    • Be warned that if you create a complex filter as part of a schedule, then apply a view template, your filter could be overridden by whatever is in the template - never to be retrieved.
  • There is a huge list of system parameters that are not available for use in Schedule Filters - way too many to list here.  Autodesk are slowly adding new ones with each release, but it is a very slow feed, rather like an old-fashioned coffee filter that is clogged up with coffee grounds.
  • Shared Parameters created in loadable Families are available for use in Schedule filters - this is a good thing (but not consistent with View Filters).
  • Schedule Filters do not allow an 'OR' rule - this is a really bad thing (and not consistent with View Filters);  they only allow 'AND' rules.
  • Schedule Filters have a fixed number of 'AND' rules - currently 7 (this was increased to 7 a few years back).


More on Schedule Filters in another blog post . . . .

Browser Filters

Project Browser has its own filtering system:

  • It is limited to 3 'AND' rules, which includes some System Parameters and Shared Parameters

  • A few years back Autodesk added "Family" and "Type" as separate parameters for filtering, which is much better
  • Unfortunately the default filter "all" is by the combined "Family and Type" parameter, which cannot be edited - I would prefer the "all" filter to be by "Family" and "Type" as two separate rules.

Parameter Search Filters

A few years back (v2017) Autodesk added a new filtering function to a couple of dialog boxes.  They referred to them as "Search" capabilities but really they are just filters - which adds to the confusion.

Global Parameters Dialog Box

There is a 'Search parameters' box at the top of the dialog.

If you type in a word or part of a word, it does not search for parameters containing that (part)word.  What it does is to filter the parameters in the dialog so that it only displays those containing the (part)word in any of the columns (parameter, value or formula);

  • Any parameters not matching the filter are hidden

I seldom use this capability - partly because the way it was implemented is quite confusing.  No doubt there are people out there who love it!

It can catch the unsuspecting user out - if you don't realise that the focus is in that Search box, and you type something in (say a value that you are trying to input in a parameter), then all your parameters may disappear.  This could be very disconcerting.

I think it would have been easier to understand if the Parameter grouping titles did not get hidden.

Family Types Dialog Box

The same capability is also available in the Family Types dialog in the Family editor (since v2017).

The same gotcha/confusion is also available in the Family Types dialog in the Family editor.