Clash Preventor

Clash Preventor

BIRD Tools

Digitally signed app




The future of coordination lies in Clash Prevention.

Clash Preventor is an add-in for Autodesk® Revit® that allows the user to prevent clashes by running clash prevention tests while he/she works.

The tool automatically tests modified elements for clashes. A manual mode also exists allowing the user to check selected elements, visible in view elements, or all elements for clashes as well.

The user can filter elements by category, knowing that Revit Links and IFC links are supported by this tool as well.

When clashing elements are detected, the user is allowed to navigate and visualize clashes in 3D by automatically creating a section box around the elements, and has the ability to tile all open views when he proceeds to solve the clashes for better visualization. The built-in Clash Browser automatically generates a Clash Report that simplifies the clash resolution process, and that can be exported to an Excel spreadsheet, which can also be imported later on.


The tool also includes a Navisworks Report Import mode where users can import HTML clash detection reports generated by Navisworks straight into Revit for easier visualization and clash resolution process.

This tool is a huge time saver as it prevents clashes without wasting the user's time, and because it helps reduce clashes it then reduces the time usually wasted on detecting and solving clashes through conventional clash detection tests.

Revit 2018-2019-2020-2021 editions are all supported.


1. To subscribe to this app please visit our website: or contact us at

2. Company multi-seat licenses are available for a discounted price. Visit our website for more information:

Trial Description

30 Day Free Trial

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About This Version

Version 2.0, 2/18/2021
- Added support for Revit 2021. - Added support for Point Clouds. - A new mode has been added that selects, zooms to, and temporarily colors clashes in all opened views as soon as you select them in the list. - Added a clash colorize mode that permanently colors clashes in the opened and active view. - Added feature to customize the required colors. - Added a new mode that imports Navisworks HTML reports into Clash Preventor's Clash Browser. - Multi-threading: the tool uses all available cores to check for clashes, which makes the clash detection process 8 times (number of cores dependent) faster than before. - Before running any clash detection study, and if it needs more than 30 seconds, the time required would be estimated, using an advanced technology that uses machine learning to determine and improve time estimation over time based on each user's hardware specs. - Users can now select categories for each link, and leave links blank in case they should be excluded from the clash detection studies. - Users can now specify the 3D view name and its section box offset. - Added a whitelist mode. - The tool now remembers the clash report and "whitelist" for each project and throughout Revit sessions. - The total number of clashes is now shown in the Clash Browser - Added a tolerance mode that whitelists elements based on a geometric tolerance. - Added support for clash filtering based on phase. - The export now supports XLSX file format. - Added a new smart clash sorting and grouping feature, by element Id or by element category name. - Fixed several minor bugs.

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Customer Reviews

(2 reviews)


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  • Promising Add-in
    David Miller | January 02, 2020 Verified Download (What's this?)


    This app is a well-developed tool for realtime collision detection in Revit. The price of the add-in is very competitive, considering that options for realtime collision detection natively in Revit are limited, and other options cost hundreds more. Very well done Bird Tools.  I know that this add-in will only become better as updates and improvements added to the app.


  • very useful tool
    Stefan Pandaciuc | November 14, 2019 Verified Download (What's this?)

    Very useful tool, even if you should only use the real time clash detection functionality.



    •Everyone remarked the increased projects quality result (clashes with other technics, not enough space in shafts, ceilings, technical rooms etc.) and time saved using it;

    The tool is really simple and powerful, and it can help us step-up to the next level of the clash detection process;

    •It saves time when modeling in 2D views as you don`t have to keep a 3D view opened for checking;

    •It eliminates the need of Navisworks software and time loss for exporting models;

    •It would be a good practice way of working in Revit right from the early stages of the project;

    •It helps newcomers to develop an aware mode of working.

    All the reasons stated above helps us improve our current clash detection workflow which will result in better coordinated projects in less time and with less money spent.

    Requests for improvement:

    •It would be great if the user can select in more detail, the categories of elements from the linked model (Walls from linked model - structural model – and not all walls);

    •Was tested in a large project, and to check the clashes in a view it took more than 10 minutes (over 1.000 elements);

    •There are clashes which are accepted, for example a pipe thru some walls. A great feature would be to mark these kinds of clashes as reviewed;


    •Overwrite the elements graphics with red and green for example, when viewing the selected clash in 3D. It would help a lot the user

    Bird Tools (Publisher) | November 22, 2019

    Thank you for your positive feedback. We will make sure all the features are added to the App as soon as possible, and we'll make sure the next version will have an even more optimized performance.

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