This guide describes features and functionality of Revit families of hangers and supports, which were created specifically for MEP Hangers software.
Families of hangers and supports can be found in sample projects on the MEP Hangers e-help page.
Library of Hangers and Supports
The library of Revit families for MEP Hangers consists of generic products that are common for supporting and hanging ducts, pipes, cable trays, and conduits. Note: this library can be supplemented with additional content if there are a significant number of user requests for specific products.
Revit families of hangers and supports are created using hanger components (as shared nested families) – that enables easy customization and accurate bills of materials through Revit schedules. That also means that these components are uploaded to the project alongside the main hanger family. Complete Revit families of hangers and supports have names that begin with “Hanger_”. Deleting hanger components from the Project Browser might affect the appearance and features of main families.
We have metric and imperial versions of Revit hanger families available.
Visibility of hangers can be controlled via Visibility/Graphic Overrides. All complete hanger families and most of the components are elements in the Structural Connections category; only unistrut channel and cantilever arm families are Structural Framing.
Small components (such as bolt, hex nuts, washers, anchors, etc.) are assigned to the “Bolts” subcategory. This means that their visibility can be disabled without turning off the entire category. The same thing can be achieved by setting the Detail Level of the view to Coarse.
Extensions and Offsets
Most of the two-rod (unistrut hangers) or two-leg (rooftop supports, rigid unistrut frames) families have the functionality to be extended to either side. Families with such functionality have the “Extension Left” and “Extension Right” instance parameters under the Dimensions group. Negative values can be entered here as well. Unistrut and rod lengths are updated accordingly.
The length of the cantilever arms can be extended as well. This is controlled by the “Cantilever Extension” parameter. Cantilever families have a small default value (10mm for metric and 3/8” for imperial) for the extensions. Cantilever extension can be useful for when another MEP service needs be supported by the same cantilever or to allow another hanger to attach to it from either above or below.
Our Revit families of rooftop supports, rigid unistrut frames, and unistrut hangers come in two versions: “Above MEP” and “Under MEP”. This simply means that these hangers and supports can be inserted below MEP services (so that MEP elements rest on it) or above, allowing another hanger to attach to it from below. For “Above MEP” families, an offset from the MEP service to the hanger bottom is needed to have enough space to place another hanger. This offset is provided by the “Unistrut Offset from MEP” parameter. Default offset values for “Above MEP” families are 100mm for metric and 4” for imperial versions.
“Under MEP” families also have the “Unistrut Offset from MEP” parameter. This parameter can come in handy when the hanger or support is placed for other hangers to attach to it from above.
“Unistrut Offset from MEP” for individual hangers or supports can be changed any time after insertion, and all the supporting elements (vertical rods or unistruts) adapt accordingly. Default values of offsets can be changed by modifying the family.
Although cantilever supports also have an offset parameter, they don’t come in “Above MEP” or “Below MEP” variants. Cantilever positioning is controlled by other means – more on that below.
Our Revit families of hangers and supports are created to cover as many situations as possible while designing MEP systems. For that reason, families have Yes/No parameters that control their appearance, size, and positioning in the project. Here, we will cover what other parameters are available for users to design and customize hangers and supports in Revit.
Some parameters are created as instance parameters (enables users to modify parameters separately for every instance) or type parameter (applies to all instances of the same type). Users are free to change type parameters to instance if there is a need to control a certain aspect individually.
“Over Insulation” (type parameter) defines if the hanger should be dimensioned according to the outer layer of insulation of a pipe or a duct. Every hanger family has this option, and the value is “true” by default. Setting it to “false” means that the insulation will be ignored.
Note: adding insulation after a hanger has already been inserted won’t change the size of the hanger, even if “Over Insulation” is on. That’s because the “Insulation Thickness” value is only transferred to the family when specific MEP Hangers commands (Insert, Update, Modify) are used.
“Use Unistrut Increments” (type) is only available for unistrut hangers. When “true”, the unistrut part of the hanger is being sized by the increment specified in the “Unistrut Increment” parameter.
“Ignore MEP Slope” (type) – controls how rods or unistruts (if it’s a unistrut frame hanger) behave. By default, this parameter is “false”, which means that rods of the hanger (or unistruts of a frame support) will always be vertical, even if on a sloped MEP service. If set to “true”, rods will be placed perpendicular to the MEP service.
“Flip Cantilever Side” and “Rotate Cantilever 90deg” (both instance) can be found only in cantilever families. “Flip Cantilever Side” moves cantilever to the opposite side of the MEP service. “Rotate Cantilever 90deg” places it in a way that the base is in a horizontal position.
“Cantilever Profile Facing Down” changes the appearance of the cantilever by flipping the profile. “Open Side Up” does the same but for unistrut hanger families.
“Reverse Slope”, “Cross Slope”, “Reverse Cross Slope” – all these parameters are created to help with sloped surfaces (such as roofs or floors). MEP Hangers software can read the slope value of the structure (if it has one) and push it to the families where it is used to calculate additional changes in rod length. However, the software cannot determine the direction of the slope (yet). For now, this can be fixed by user input.
“Reverse Slope” (instance) uses the opposite value of what the software initially thought the direction of the slope is. It is only needed when both the MEP service and the structure are sloped and their slope directions are opposite.
“Cross Slope” (instance) parameter is needed when an MEP element is under a sloped surface and the slope direction is perperdicular to the direction of the MEP element, causing the rod lengths to be different according to the slope value. “Reverse Cross Slope” (instance) changes rod lengths – it is needed when the surface slope is going in the opposite direction.
Vertically modelled rectangular Revit MEP elements (rectangular ducts and cable trays) can sometimes have opposite width and height values but look identical. That’s because Revit assigns width and height values based on the view that the element was modelled in (plan view, section view). If hangers appear incorrectly when placing them on a vertically modelled rectangular duct or a cable tray, that might be because of this issue. To fix it without remodelling the MEP services, simply use the “Reverse Width and Height” (instance) parameter.
“Drilling Points Visible” (type) controls visibility of marks that represent drilling points. Drilling points are created as nested families inside hanger families and turning off this parameter will remove their presence inside of the main family. This can slightly improve the speed of hanger insertion.
Click here to read more about drilling points and how to use them.