In the last few releases of Revit, Autodesk have been working towards a fully independent analytical model that can be used for preliminary design. This can then be ‘converted’ into physical counterparts with the use of the Analytical Automation using Dynamo Player.
Since Revit 2025, we now have access to analytical nodes that can be hosted onto grids, levels, and grid intersections. This new functionality allows for new levels of intelligence when it comes to the authoring of typical structures such as portal frames.
In this post we will look at how a portal frame can be built that can adapt to bay size changes, height, roof pitch and portal spans.
The most important first step is to create a grid that is controlled with Global parameters. This may be a feature that many of you do not use regularly within projects, but this is very useful for the hosting of analytical members ant the overall control of the model. In the image below you can see a grid that is being controlled with Global parameters.
The rafters are controlled by using a formula with takes the roof pitch and calculates the ridge height.
Framing and bracing positions and connections can be controlled with segment length dimensions or normalised curve parameters. In the example below you can see a plan on a framing bay. The 3 secondary members shown in orange are controlled with normalised curve parameters so the secondary members will move when the primary element changes length.
To understand more about this new control, feel free to watch the YouTube video showcasing a portal frame model.
LawrenceH
Autodesk Revit Structure 