BIM Clash Detection: A Quick Guide

BIM Clash Detection: A Quick Guide

Clash detection is one of the most critical steps teams can take to identify and mitigate potential design conflicts before breaking ground, thus preempting construction issues and rework.

Clash detection has been around for some time. And while you can technically carry out the process manually—i.e., by reviewing details in design drawings or using a light box overlay —the advent of BIM tools has made the process easier and more accurate.

That’s why BIM clash detection has now become the standard in commercial construction, and it’s implemented in a project’s earliest design and preconstruction stages.

In this guide, we’ll explore the ins and outs of BIM clash detection. We’ll shed light on the best practices and top tools you can use to avoid construction clashes and elevate overall project quality.

What is BIM clash detection? 

BIM clash detection is a process that identifies and addresses conflicts among at least two construction models in a virtual environment. These conflicts, or “clashes,” arise when different design components, such as structural elements, HVAC systems, or electrical conduits, intersect or interfere with the buffer zone of another object.

Architects, MEP engineers, and structural engineers often independently create models during the design process. As such, when these separate models are aggregated into a single project model, there’s a risk that the individual components would inadvertently overlap or interfere with each other.

BIM clash detection highlights these clashes early in the preconstruction or design process, which helps prevent costly adjustments and delays during the construction phase.

BIM clash detection determines where design aspects may overlap and creates constructability issues so teams can resolve them before moving to the next stage.


What is automatic clash detection?  

Automatic clash detection can be implemented in one of two ways. First, a more manual version of automatic clash detection is when a BIM expert sets up a series of tests using several conditions, and the process is repeated for every new version.

Another way of approaching automatic clash detection removes the initial setup process and the need for specialized expertise. This second method works by simply adding relevant models into a cloud-based file where they’ll be aggregated and clashed automatically. Since this method clashes everything together at once, BIM experts and non-BIM experts alike can then use filters and groupings to narrow in on items they’re interested in. The resulting benefit is an immediate clash result and accessibility to all team members, regardless of their level of expertise or role. This immediacy makes it possible to pick up clash information directly in the authoring tools. So once a design decision is made, architects and engineers can see the impact of the change in real-time.


What are the benefits of BIM clash detection? 

Harnessing the power of BIM clash detection comes with several advantages that can revolutionize how your construction projects are managed. Consider the following.

Save time and money 

Since clashes can be identified and resolved before work onsite gets started, project teams save time and money by staving off the costly impacts of wasted materials, labor, and reworking physical properties. Teams can confidently move forward into the construction phase instead of worrying about what a new setback tomorrow might bring.

Beyond this, BIM clash detection reduces the stress and logistical complications of last-minute changes, allowing the project team to focus on delivering positive project outcomes for their clients and their partners.

Outcomes like jobsite safety. By reducing the risk of unexpected issues, on-site incidents are mitigated, and project leaders can manage their teams with safety at the forefront.

Minimize risk and waste 

In addition to mitigating budget and schedule overruns, clash detection can improve productivity through smarter scheduling, material waste reduction, and installation efficiency.

As project stakeholders eliminate potential issues early on, project managers have the insights they need to drive toward timely delivery and exceed client expectations.

BIM clash detection can also minimize material waste. It allows teams to be more precise with their project planning, so they can order and utilize materials more efficiently and eliminate waste.

Enhanced collaboration 

Projects undoubtedly see better outcomes when teams work together seamlessly. BIM clash detection paves the way for enhanced collaboration between different disciplines (architecture, structural engineering, MEP, etc.).

When clashes are identified, all relevant parties must work together to resolve them, ultimately promoting better coordination across stakeholders.


Types of clashes 

Optimizing BIM clash detection involves familiarizing yourself with the various clashes that can occur in a construction project. Let’s break them down below.

Hard clash 

A hard clash occurs when two systems and components take up the same place or intersect.

For example, a structural beam might be positioned where an HVAC duct is intended to go, or a plumbing pipe might be designed to run through an electrical conduit. These are physical conflicts in the design that, if not corrected before construction, could lead to significant rework.

That said, hard clashes are the easiest to identify—though they’re incredibly costly if you miss them.

Soft clash 

A soft clash (sometimes called a clearance clash) occurs when a building element or component has not been given enough space or buffer to operate effectively and safely. This might involve maintenance access, safety clearances, or operational spaces.

One example could be if the AC unit doesn’t have enough buffer space to be serviced by a professional. This could hinder routine maintenance and lead to extended downtimes, affecting the building’s comfort and efficiency.

Similarly, safety issues like a high-voltage wire being too close to a plumbing line could constitute a soft clash. Any leakage from the pipe could lead to an electrical short circuit or, worse, pose an electrocution risk to maintenance personnel.

While soft clashes don’t involve physical overlaps, they still pose significant challenges that could compromise the building’s safety, functionality, and maintainability. Fortunately, these issues are flagged early on with the right BIM clash detection tools, so you can resolve them before hitting the jobsite.

Workflow clash 

A workflow clash, known as a 4D clash, involves a scheduling conflict or project management misalignment. For instance, if the installation of electrical conduits is scheduled at the same time as pouring a concrete slab in the same area, it could result in work stoppage, rework, and delays.

Or, if large equipment is delivered to the site before the area is ready for installation, it could lead to space constraints or damage to the equipment.

Workflow clashes can hinder jobsite productivity when they’re not caught on time. As such, identifying and addressing them through BIM paves the way for optimal scheduling and sequencing.


How BIM clash detection is evolving 

While BIM clash detection has undoubtedly been a game changer for construction pros, there’s still room for improvement, particularly regarding clash management.

Today, BIM managers do a lot of pre-coordination meeting work, getting the whole project team to discuss and resolve issues. However, many of these meetings often focus on low-impact matters—e.g., fixing simple clashes and double-checking that previous issues were resolved.

And while this level of granularity is necessary, teams need to develop a hybrid approach to clash management—one that involves continuous model coordination between engineers, architects, and trades.

Accomplishing this requires a shift in mindset and practices. It means getting the entire team involved in clash detection and ensuring they collaborate throughout the week to find, prevent and fix design conflicts and misalignment.

When issues are resolved on an ongoing basis, meetings can focus on high-priority issues, freeing BIM managers to devote their expertise to resolving more significant challenges. This optimizes everyone’s time and encourages a more proactive, collaborative, and efficient approach to BIM clash management.

All to say that a streamlined approach to clash management allows you to uncover the full potential of BIM technology, so you and your teams can further drive project success.


Top clash detection software 

Speaking of streamlining BIM clash management, the best way to unlock efficiencies in your processes is to leverage clash detection software—ideally, one that’s cloud-based.

The right tools automate repetitive tasks, reduce the set-up time to near zero, and work with the tools people use daily. That way, teams can spend less time manually searching for conflicts and devote more energy to resolving clashes.

To that end, here’s a look at the top clash detection software for your construction projects.


Navisworks is one of the most powerful tools in the market for coordinating construction projects. With its advanced clash detection capabilities and quantification tools, Navisworks helps users ensure that models are ready for construction.

On the scheduling and budgeting side, Navisworks’ 4D and 5D simulation lets you animate and interact with objects and create schedules directly from models. You can also import schedules and cost items from third-party project management applications to ensure the smooth coordination of all project components.

Beyond just detecting clashes, it also allows teams to validate and collaborate on proposed resolutions in a shared environment.

Autodesk BIM Collaborate 

Coordinate teams and models from one place using Autodesk BIM Collaborate. The software enables project members to upload models, detect clashes, and resolve issues in real time. Enjoy unlimited projects and file storage, and rest easy knowing that all your info is secure and accessible.

And with mobile-friendly tools, stakeholders can view models from anywhere, so decisions can be made sooner rather than later.

Navisworks + Autodesk BIM Collaborate = a match made in construction heaven 

Navisworks and Autodesk BIM Collaborate are powerful tools that work even better when used together.

Combined, these solutions massively benefit multiple teams and stakeholders throughout the project lifecycle.

Let’s start with BIM Managers. BIM Managers can use the Navisworks Coordination Issue Add-In to monitor the status, responsibility, and resolution of every issue across multiple projects. And since files are saved in the cloud, users in Navisworks can work on those files simultaneously, fostering real-time collaboration and promoting a seamless workflow from clash detection to resolution.

On the VDC side, teams can decide where to carry out clash detection for a specific project or phase.

Autodesk BIM Collaborate also lets users deactivate clash detection in certain coordination spaces. This feature offers rapid access to complex files in Navisworks while ensuring stakeholders can use essential workflows like Issue Management and Model Aggregation online.

Moreover, BIM Managers can create custom views in Autodesk BIM Collaborate, which means they can develop views for individual objects, disciplines, categories, or types from multiple models. This gives VDC teams more control over project information, so they can deliver only the most critical construction data to stakeholders in the field and across other companies.

In Autodesk BIM Collaborate and Navisworks, clashes can be organized into groups, enabling users to quickly review and generate batch issues from these grouped clashes. These groups serve as templates for clashes that share similar attributes, empowering users to address multiple errors simultaneously.

And the best part? All of these things take place on the Autodesk platform. In addition to offering a single source of truth, project stakeholders can work collaboratively in a shared environment, facilitating seamless communication, improved coordination, and streamlined decision-making throughout the project lifecycle.



Experience the future of BIM clash detection 

BIM clash detection is vital in modern construction, enabling project teams to identify and resolve design conflicts before construction begins.

And by leveraging BIM clash detection tools like Navisworks and Autodesk BIM Collaborate, construction professionals can streamline the clash detection process, saving time, reducing costs, and increasing the project’s overall quality.

Robotech CAD Solutions can help you find the best software to fit your needs. For over 30 years, we have been an Autodesk Reseller, implementing Autodesk Solutions. Contact us to learn more.

Issue Resolution and Clash Avoidance with Autodesk BIM Collaborate

Issue Resolution and Clash Avoidance with Autodesk BIM Collaborate

ACC Blog - Round Trip Issues BIM Collaborate

Construction management is a highly complex and multi-dimensional collaborative effort. To execute on projects effectively, several people and moving parts all need to click and stay in sync. Issues need to be resolved quickly, questions must be answered in a timely manner, and there should be trust and accountability across the entire team.

Accomplishing all that, however, is easier said than done.

Design and construction teams struggle to find a seamless way to identify issues and circulate them to the appropriate stakeholders. Often, teams rely on spreadsheets, static reports, or third-party management solutions to gather information and make decisions.

Unfortunately, these tools and sources are unreliable and inaccessible to the wider team. They cause confusion and are ultimately ineffective for detecting clashes and resolving issues. Not to mention, the manual tasks involved with static documents and spreadsheets are tedious, time consuming, and can cause issues to slip through the cracks.

The result? Issues that could’ve been avoided bubble up to the surface later on in the form of rework — and unnecessary costs. Clashes alone account for 5% of construction spend and 52% of the $280 billion of annual rework costs are caused by poor project data and communication globally.

To address this, many companies turn to third-party point solutions to address specific problems. However, these programs usually require further training and implementation, as well as additional costs.

To make matters more complicated, the different parties involved (e.g., design firms, GCs, and subcontractors) all use different systems and platforms. The JBKnowledge 2020 ConTech report found that 63% of construction pros are using three to six more apps  — which makes integration and communication harder and limits project data usage.

All this to say that managing project issues in construction can be a headache.

What if you could address issues at the same time and at the same place, to streamline resolution?

The combination of Autodesk BIM Collaborate (part of the Autodesk Construction Cloud platform), Navisworks, and Revit makes all that possible.

Thanks to the tight integration between these solutions, issues can be created, managed, or resolved directly in the tools you work in daily, and are connected using a common data environment (CDE).

By surfacing and resolving issues in a CDE, you create a lasting history of decisions made for downstream stakeholders for future reference. It also allows multidisciplinary teams with different tools to manage and communicate about issues using a common solution.

All in all, this paves the way for a roundtrip workflow, which helps teams close the loop with any clashes or issues that arise.

Issues created in either Autodesk BIM Collaborate or Navisworks can be assigned and contextualized in either of those tools and resolved in Revit. That resolution then makes its way back to Autodesk BIM Collaborate for reporting and future project forecasting.

Let’s take a look at just one of the ways all these solutions work together.



Autodesk BIM Collaborate

Autodesk BIM Collaborate’s browser-based model coordination and design collaboration tool comes with automatic clash detection and grouping tools that help identify issues early on. The software’s UI is intuitive and easy on the eyes, so all discipline types (designers, GCs, and specialty contractors) can use the solution.

Team members can self-check their work as they go, and if issues come up, they can flag it with a location pin and add details such as the root cause, description, important dates, and clash screenshot. From there, they can assign the issue to the appropriate stakeholder.

Because multiple stakeholders can take part in identifying and assigning issue tasks, the coordination process is faster and much more streamlined. Issues and their associated models are stored in a common data environment for multi-team, product, and construction phase access to action on.



Navisworks Coordination Issues Add-In (Navisworks 2021-2022)

This Navisworks add-in connects models, views, and issues through a CDE, so BIM/VDC managers can easily create, track, assign, and resolve issues directly in their desktop application.

If a Navisworks user is unsure about an issue, they can simply comment directly within the platform. Similar to Autodesk BIM Collaborate, users can add issues and include details like type, location, assignee, description, and due date. They can then pair that issue with an image snapshot of the clash identified. Thanks to this add-in, stakeholders using the software can better contextualize the issue, resolve it, or assign it to someone else.

Navisworks also has an updated Coordination Space and Append capabilities. With the upgraded issues add-in, users now have the ability to append additional models from a Model Coordination space to their already opened set of models. This increases the efficiency of coordination meetings by allowing users to immediately update your .nwf files as new model files arrive from project design teams.

Plus, this free add-in seamlessly connects with Autodesk BIM Collaborate and Revit, so there’s no need for third-party integrations. You’ll reduce manual work and miscommunication, and resolve issues more quickly.

See for yourself by downloading and installing this add-in from the Autodesk App Store. Once installed, start Navisworks and navigate to the Coordination tab.

Revit Issues Add-in (Revit 2020 or later)

Using the very same common data environment and issues layer, architects and engineers working in Revit can scan through all the details we covered above and any additional information from the comments/history, to resolve the issue directly in the model.

This type of connectivity displays the same information to the entire project team, thus enabling stakeholders to literally stay on the same (digital) page. Stakeholders benefit from having more transparency and greater levels of accountability which result in less rework from issues slipping through the cracks.

Instead of waiting until the next coordination meeting to resolve an issue, users can continuously collaborate on models, speeding up time-to-site and reducing the expensive design iterations that occur from poor and sporadic communication.

You access this add-in from the Autodesk Desktop App or your Autodesk account. Get more info on how to use it from the Autodesk Knowledge Network.



Bringing It All Together

Autodesk BIM Collaborate, along with the Navisworks and Revit add-ins, take issue management to a whole new level.

These tightly integrated tools don’t just let you track or manage issues, they create an environment to collaborate and resolve them.

Issue resolution is tracked in Autodesk BIM Collaborate with a dashboard of outstanding issues and resolution overtime, paving the way for better management and prediction for future projects.

Plus, the entire project team can work together to resolve issues and collaborate with a “clash avoidance” mindset (as opposed to a “clash detection” mindset). This speeds up the time-to-site and reduces costly rework.

With a roundtrip workflow, issues are created in either Autodesk Construction Cloud or Navisworks, and actionable in Autodesk BIM Collaborate, Revit, or Navisworks, bringing the best of each environment to your next project.

Interested in experiencing Autodesk BIM Collaborate for yourself? Request a trial today.

5 Ways Digitalization Fosters a Collaborative Culture in Architecture

5 Ways Digitalization Fosters a Collaborative Culture in Architecture

collaborative architecture cannondesign team

The CannonDesign team collaborates using VR and other visualization tools. Courtesy of CannonDesign.

In 2017, CannonDesign broke ground by hiring Hilda Espinal as its first chief technology officer—a surprisingly uncommon position for large architecture and engineering firms.

With her background in architecture, information technology, and project management, Espinal helps the firm use technology to develop better design and stronger partnerships. This approach, she believes, leads to higher productivity, competitiveness, and profits for everyone involved in a project, from the designers to the builders to the building occupants. Firms might once have kept information close in the name of differentiation, but Espinal is seeing more of a collaborative spirit in the industry: an open-sharing environment that helps everyone start the race from farther down the track.

Though Building Information Modeling (BIM) is at the core of this shift, Espinal says a culture of sharing has spurred other practices, such as bringing subject-matter experts in-house for planning and design. Here, Espinal offers five lessons that illustrate ways digitalization is transforming the culture of collaboration for architects, engineers, contractors, and occupants and owners.

collaborative architecture kaiser permanente radiation oncology center in anaheim, california

CannonDesign’s in-house medical experts collaborated with the firm’s designers on the Kaiser Permanente Radiation Oncology Center project in Anaheim, CA. Courtesy of CannonDesign.

1. Sharing Information Facilitates Progress

Project delivery is not a linear process, but it’s often presented that way, Espinal says. In reality, many aspects of it are often cyclical, and therefore, the opportunities to share information are rich. “I’m a licensed architect, and while our expertise is crucial to a project, it is limited,” she explains. “Imagine how much better it would be if we had the additional insight of a contractor—early on—to help further educate us on constructability realities and help each other avoid design-to-build pitfalls. Because when we operate in silos, we are simply not equipped to foresee.”

When computer modeling first became part of design, it required such a massive investment of technology, time, education, and content building that firms were reluctant to share information, Espinal says. Now, the technology has evolved to a point where nearly everybody in developed economies can access it. Espinal hopes that best practices for using modeling and visualization software will be established for each industry sector; adopting a common approach could get people at all stages of a project on the same page much quicker.

“Information is power—when it’s shared, not when it’s kept to yourself,” she says. “That’s when we start to evolve and improve upon each other’s knowledge. Being able to free resources up, it’s ultimately going to benefit the actual product, whether it’s a building or a city.”

3. Collaboration Must Begin Within

In the next five years, Espinal says she’d like to see more digital collaboration happening within design, engineering, and construction firms, which will lead to better information sharing with other collaborators. On a strategic level, firms can start by having conversations about what they’re comfortable sharing and what they aren’t, so it’s all very intentional.


UC San Diego Health’s Jacobs Medical Center. Courtesy of CannonDesign.

“Knowledge sharing and knowledge capture really need to grow at the micro level and within our own firms, where we should make a more concerted effort toward digitizing our knowledge,” she says. “You need to not just have it all in your head; you need to record it somewhere and make it accessible and shareable. That’s the very first step.”

Because CannonDesign’s portfolio includes major health-care projects—such as UC San Diego Health’s Jacobs Medical Center and the Kaiser Permanente Radiation Oncology Center in Anaheim, CA—the firm has taken the uncommon step of hiring staff medical professionals that are integrated in project design from the get-go. Its practice, therefore, includes early advisory services all the way through post-occupancy engagement and facility-optimization solutions.

4. Visualization Software Is Here to Stay

There are many ways to approach client collaboration. When CannonDesign created the new student center for Toronto’s York University, for example, it engaged 11,000 students in every aspect of the process, working to ensure that inclusivity and wellness were at the forefront of the design. Designers are trained in a vocabulary of drawings. They can present building sections and elevations and convey what they represent to project stakeholders. But immersive visualization platforms—virtual reality, augmented reality, and the like—improve dialogue with clients and project partners, Espinal says.

“With the advent of technologies like virtual reality and augmented reality, we can say, ‘Here, please try on these goggles,’ and you can walk in this space and ask, ‘Does that ceiling feel too low? Does the width of this hallway feel right?’” she explains. “Now, clients can really experience design. It gives them a much louder voice to say, ‘Hey, this works; this doesn’t’—they become a further part of the design process.”

collaborative architecture York University student center Toronto cannondesign

York University’s new student center in Toronto. Courtesy of CannonDesign.

5. Information Sharing Is an Ecological Responsibility

Climate change puts increasing pressure on designers to create sustainable, resilient spaces—reusing materials, reducing waste, and orienting buildings to maximize daylight or other conditions. Because climate change poses threats to the built environment, it may not be ecologically responsible for individual firms to spend time and resources developing their own sustainability solutions when the greater community could benefit from those ideas.

“If you’re committed to being sustainably sensitive, you start to think about glazing versus opaque surfaces or about the orientation of a building, modeling it and testing options,” Espinal says. “After a few times of trying it, it becomes part of the intel.” She says designers have a responsibility to share this insight: “Ultimately, being responsible to the environment is just something we need to do and certainly not an area to be competing about. We have one earth to share and need not keep knowledge gained and best practices to ourselves.”

A Little Island is growing across the river

A Little Island is growing across the river

There has been a flurry of new construction across our office in Hoboken. It seems that every month there are new features to discover across the Hudson river in NYC. One of these new features was spotted by our resident IT guy Alberto;

“Walking to the office you can see a collection of piles and
concrete pots that form a sort of honeycomb 3D island”.

It turns out this is the work of Thomas Heatherwick Check the out the short video and if you really want to amazed visit Thomas Heatherwick’s Pier 55 site


Visit the project’s site