Groups can be one of the most misunderstood and misued features in Revit. When to use a group, a family or even parts and assemblies? Groupies know that while there is always more than one way to skin a cat, groups can offer a great solution to projects containg "typical" groups of elements (that's why they are called groups!) or to control parts of projects. Even Revit's developers seem to have caught onto this with the functionality of groups having improved in recent releases. This class will look at best practice workflows for using groups. * When to use a group versus a family * Nested groups * Naming and organising your groups * What to do about "fix groups" and other group busting errors * Tagging and scheduling groups * Creating different group instances (yes it is possible!)

1. Get your Groupon!
Ceilidh Higgins
Senior Interior Designer – Daryl Jackson Robin Dyke
Blogger – The Midnight Lunch
Twitter
@ceilidhhiggins
@BIMinions

2. why groups?

3. replication

4. groups are for repeating
• high rise facades and cores
• typical apartments
• typical rooms
• objects that have a fixed
relationship to one another

5. speed

6. groups are fast
• quick to create
• copying and amending
• annotating using detail groups

8. Groups have
become
more stable
• you can mirror *
• you can rotate *
• they don’t increase
file size
*See Aaron Maller’s talk from RTC2014 for
more on mirroring and rotating groups –
particularly for face based families

9. but…
groups
are
dirty

10. fix groups!

11. break easily

12. can’t vary

13. can’t schedule

14. alternatives

15. families

16. why use nested families
• ability to flex
• more stable than groups
• suited to single category of objects

17. problems
• more time consuming to set up
• less experienced users struggle
• cross category issues
• slower to annotate

18. nested family example
Casework – 5 different
families, all with finishes
and dimension parameters
to link through
Specialty equipment
– 2 different families Long parameter list, complex family

19. benefits
Ability to vary
dimensions
Ability to turn
elements on and
off and create
various types

20. problems
Hatch pattern
shows where bins
are present even
when category is
switched off
Different categories within the
nested families can have
unexpected results
Remove Bins and Copier
from the family and create a
group with the casework
family and equipment

21. linked files

22. why use linked files
• more stable than groups
• groups can be used
inside of linked files
• suited to whole repeating
floor plates

23. problems
• require loading families, wall types etc into
multiple files
• walls joins from the linked file won’t clean up at
intersections with elements in the main model
• time swapping between files

24. assemblies

25. why use assemblies
ability to quickly set up views

26. problems
• if you change one assembly
it makes a new one rather
than updating them all – this
includes instance based
parameters
• you can’t nest assemblies
• you can’t include groups,
links, rooms or some MEP
objects

27. creating

28. plan your groups
• is a group the best solution?
• which elements belong to which groups?
• how do your groups and worksets work together?
• which elements are best left out of groups?
• make sure there are no pre-existing
errors/warnings in elements you are grouping

29. naming
Organise and rename
your groups in the project
browser – just below
families
Detail and model groups

30. origin point
Automatically assigned
origin point
Select origin and drag it to
move it
Select dots at ends
of axis to rotate

31. families inside groups
Errors inside groups are frequently due
to just one family:
• Overall construction & quality of
families can impact on group
• Could be due to items not visible in
family type
• Check the family level and host
• Line based and face based families
can cause errors in groups – each
object needs to be hosted to its own
reference plane
To avoid breaking up the group -
remove the family from the group

32. level and host
Check the level and host for each
object before you create the group

33. Be careful – when you
copy and paste
or create similar objects,
the level and host do not
always transfer

34. You cannot rehost the
object when in the group
editing mode. You have
to remove the object from
the group, rehost it and
then add it back to the
group
Creating your family outside
the floors and moving it into
place can help solve this

35. hosted objects
The door is part of the
same group as the wall it
is hosted on
Best practice is to group objects along
with their hosts and any objects they
are constrained to

36. adding and removing
Use the plus and minus
symbols to add and
remove objects form the
group

38. detail groups
Most people discover
attached detail groups
accidentally

40. nesting

41. nested groups
Nested into kitchen
group - typical island
bench group
Nested kitchen type
3 group
Group of joinery, fixtures
and fittings for each
apartment type
Limitation of nested groups:
They won’t align!

42. export
import

43. exporting

44. inserting

45. and yes you can update them

46. linking
You can also turn your
group straight into a linked
file
But be careful if you are
using nested groups –
the nested groups may
be lost

47. worksets,
phases, options

48. worksets
The group belongs to a workset –
this is the workset that you are
working on now
When you create a new
group, the individual
objects inherit the group
workset
But when you set up the group
the worksets can differ!

49. Different instances of the
group can belong to
different worksets

50. match groups to worksets
The basin, toilet, vanity and floor
waste are a nested group – their
relationship is always consistent

51. The group is on the FFE
workset
The floor wastes
were setout on the
concrete outline
plans

52. and workflows
The floor wastes were setout
on the concrete outline plans
Different users could not
check out worksets to
work on casework and
concrete outlines!

53. phases
The group does not have a
phase

54. The phase belongs
to each object
inside the group
Phases are allowed
to vary across group
instances

55. Different objects in
one group may
have different
phases

56. Changing the phase of grouped objects is very time consuming

57. design options
The group can
belong inside a
design option

58. scheduling

59. scheduling groups
The kitchen
group appears
to have a type
tag which is
then scheduled
– but how?

61. tagging
The tag is just a
generic tag
which picks up
the type mark
parameter from
the 2D family

62. varying

63. Exclude objects
Once objects are
excluded from a group it
is as if they don’t exist in
the model – they won’t
show up in your
schedules.

64. Restore excluded
Restore excluded
objects by selecting the
group and right clicking
Tab through to select
and restore individual
objects

65. vary parameters by instance
Instance based parameters within
the group can vary across group
instances – but only for
parameters which are not
geometric

67. parameter types
Even though this yes/no
parameter does not drive
geometry, you cannot
make it vary by group
instance
Parameter types that can vary:
Text
URL
Materials
Area, volume and density
Currency

68. repair

69. understand the errors
Review the error warnings instead of just
hitting fix groups. Frequently the errors all
relate to just one family.
Is the family a line based family?
What is it hosted to?
Remove the family from the group
if necessary.

70. fix groups

71. find and replace

72. no error message
• objects appear
to be missing
from some
group instances
• error “multiple
instances in
one place”
Group is missing casework objects

73. i know they are there?
Group has casework items visible
Level 3 where the group was
created

74. The objects can be found
in 3d by isolating the group
– while they were correctly
hosted to the original level
– they have replicated all
over the place
The culprit – these
families were line based
families

75. bugs

76. design options
This project has 2 design options, when I
accept primary this is the error –
oddly the affected group only exists in
the primary option

77. Instead of breaking up the group I will
delete just the copiers. That excludes
them though, rather than removes them
from the group which doesn't sort out the
problem - Revit still wants to break up
the group.
Remove the family from the group
prior to accepting the primary
option

78. floor levels
The levels in this model were initially set
up based upon a zero RL. Later the
levels were moved to the real RLs.
However the group origin points appear
to remain at the original levels.
The building is 19 storeys tall with
groups on every floor!

79. The model was in chaos
with groups everywhere
Even if the origin points are fixed the
groups are not hosting in the right places
– this group is still on the roof even
though the group origin is Level 17

80. When I edited the group I discovered
that the objects themselves had a
different Offset – and you can’t change
the host inside the group
In this case I did break up
all the groups, but I later
found the error…

81. what’s wrong?
There are a number of nested groups of
tables and chairs inside another group.
One nested group has a strange level
issue – although it is appearing correctly in
all views

82. Exporting the group to a project is one way
to check – turns out there are 5 levels with
different parts of the group hosted to
different levels!
Rehost and delete excess
levels and replace group

83. Group Tips
• Don’t use line based families
• Do match groups to worksets
and workflows
• Don’t group elements without
elements that they are
constrained or hosted to
• Do manage your groups as
you would manage families

84. Questions?
check out my blog at
themidnightlunch.com
@ceilidhhiggins
@BIMinions
Ceilidh Higgins

85. Groups
highlight
problems
in your
model

86. Screen shots and video by Ceilidh Higgins from DJRD projects for this presentation
Question mark - http://www.flickr.com/photos/21496790@N06/5065834411/sizes/l/
Chairs - http://www.flickr.com/photos/masochismtango/283536089/sizes/o/
Runner - http://www.flickr.com/photos/thehappyrower/5821364319/sizes/l/
Stables - https://www.flickr.com/photos/charlesfred/598978125/
Hanging on (Muddy hand) - https://www.flickr.com/photos/white_ribbons/6878331747/
The weakest link - http://www.flickr.com/photos/darwinbell/465459020/sizes/l/
They are Coming - http://www.flickr.com/photos/donsolo/2886355241/sizes/l/
flip_board (Schedule board) - https://www.flickr.com/photos/apothecary/1453906842/
Options -http://www.flickr.com/photos/wespeck/3912468102/
Monkey in the Middle - http://www.flickr.com/photos/wcdumonts/8265151843/sizes/l/
Elephant walk (lineup of planes) - https://www.flickr.com/photos/29233640@N07/9729735310/
Create. (scrabble) - https://www.flickr.com/photos/doremigirl/8415177424/
Nesting (Nested bowls) - https://www.flickr.com/photos/sizima/564751829/
Exported bottle - https://www.flickr.com/photos/16210667@N02/9443836273/
La libertad tiene un precio (options) - https://www.flickr.com/photos/maduixaaaa/2567638237/
Cars in bucarest - https://www.flickr.com/photos/joyoflife/1570126182/
Preying mantis Lawn Mower - https://www.flickr.com/photos/terykats/5960340452/
Pointing hand - http://www.flickr.com/photos/spotsgot/3288913/sizes/l/
Lonely number 1 - https://www.flickr.com/photos/lioil/89153726/
Image credits