Maximizing VDC in Prefab and Modular Strategies on a Renovation Project

DAVID STONE: Hi. Thanks for joining us today for Maximizing VDC in Prefab and Modular Strategies on a Renovation Project. My name is David Stone. I'm the VDC leader for our Northeast team.

I've been in the industry for 23 years now. Started on a design side, and been most of my career on the construction side. And love working on this side. So with that, I'm going to turn it over to Finn to introduce himself.

FINN WANG: Hi, everyone. My name is Finn Wang. I'm a VDC engineer with DPR Construction supporting the DC and Baltimore office I've been in the construction industry for seven years. And I love what I'm doing and keep building great things with DPR.

DAVID STONE: Awesome. So basically, we'd like to share with you the DPR core values because I think it makes a big difference for us. And it's what attracts a lot of our team members to get excited about what we do, integrity, enjoyment, uniqueness, and ever forward.

A little bit about DPR footprint. We're an international company. Our headquarters is in Redwood City in California. But we basically have a family of companies that support the DPR mission, including prefab and design. And we are made of approximately 10,000 team members currently. It's about one to one ratio between our hourly and our salary staff.

And a little bit about rankings. At DPR, we really care more about being the best at what we do. But it has been informative for our audience to understand where we sit at different markets. And probably the one that's most familiar to people is the ENR top 400 rankings, which currently, we sit at number six.

And a little bit deeper dive into our core markets so you get to know a little bit about what we do as a company. These are our five core markets. Advanced technology, typically, those are data centers. Health care, hospitals. Higher education, typically, colleges, universities. Life science, typically comprise of pharmaceuticals and research facilities.

And then on the commercial, that captures a lot of different types of projects, obviously, office spaces. And in our case, the project that we're going to present to you is multi-use type project that includes hotel, office, and restaurant and retail space.

So jumping into our project. So we call the project RMR 20 Mass Ave. RMR is our client developer. 20 Mass Ave is the location.

So what you can see on the map here is that wedge-shape in red represents our project. It's about one block East of Union Station. And it's about-- three blocks South of us is actually the United States Capitol that you can see below. And then 1.5 miles West of us, which you can see on the map as well, is the White House. So it's a very busy area.

And in the next image here, you're going to see the building as it was designed post-renovation. And it started out as an eight-story building. We've actually added three stories on top, which you can see in green here.

And we also added an entire strip on the edge of the building that's highlighted in purplish-blue to the footprint of the building. And the red area represents the new atrium that we carved into the building. In addition to that, our focus area is going to be on the prefabrication and modular construction, specifically, the 206 SurePods modular bathrooms that we've constructed for this project.

So, the next slide is now for Finn to go through our agenda. Take it away, Finn.

FINN WANG: Thanks, David, for giving the introduction. So this is how we're going to present this case study to everyone is through these four steps. First is to explain what challenges has been identified and what's the constraints and what are the goals to achieve. And then to achieve the goals, what data and tools we need to have to enable our VDC workflows.

And then we're going to dive into the workflows to take a look how we leverage to tackle all these challenges. And in the last section, we're going to showcase some of the outcomes of our VDC exercises and how they lead us to the successful implementation of the project and how work has been put in place in the field.

All right, let's start with identifying the challenges. So one of the biggest challenges on this project is the existing site conditions because of the nature of this project, right? So this is, in general, a renovation project presents great complexity due to the need to work with the existing conditions. In this case, we are reusing all the structure of the building.

And because this building is being repositioned from a office building to a mixed use, including restaurant, hotels, retail, so the amount of the new HVAC and plumbing scope is much greater than an office building, as you can imagine. But it has a limited floor to floor height, right? So the coordination of the space is going to be very challenging.

And in addition to that, with the location of this building being in the busy area in downtown Washington, DC, it also makes the logistic and scheduling, safety planning very intricate. So how to get the materials into the building become a focus point of the project team.

Also, on the West side of the building-- you can see on this image right here-- it shows how close that adjacent building to our project is. See that narrow alley site? So making sure the alley has the access to our project as well as to the adjacent buildings parking entrance is very challenging. And of course, there's other unforeseen conditions here.

And then after the team dug into the details of the project, we saw an opportunity to engage SurePods. David mentioned SurePods is the prefabrication vendor who fabricates the factory-built modular bathroom pods. And as you can see, this is the floor plan from the architectural design floor plan. There's a lot of identical bathrooms.

So we ended up having 206 bathrooms that we use SurePods. Some of the bathrooms, due to other constraints, that they cannot be SurePods. It's better to be stick-built. So we have over 200 parts fabricated by SurePods.

That saves us 10% in schedule, as well as they were completed with a predictable result by fabricating in a controlled environment. And the fabrication is going on simultaneously with the other construction activities. So that saves a lot of time and let the team be able to focus on other construction activities within the building.

So this is why we're doing this case study is to see how VDC can support these modular building components to be successfully implemented in the renovation building. With that being said, SurePods surely brings great value. But it also brings higher requirement for better planning, coordination, and most importantly, scheduling, which leads to the next slide, the schedule challenges.

So in order to take full advantage of the schedule reduction brought by using the SurePods, it has become critical to optimize the construction schedule, as any mistake may occur on one pod and be multiplied by 260 units, which can be a significant cost impact. Also, there's an extremely small delivery and placement window, only three days. So everything needs to be planned ahead of time when not creating bottlenecks for other disciplines to work, reducing on-site workers for safety reasons.

And there's also some other schedule challenges like DFOW, Distinguishing Features of Work, which because the project has a complex canopy detail and exterior, as well as the alley, we are using the panel system, which we're going to cover that in the later part of the conversation, as well as the detail of the SurePods, that's very complicated. And if we're not figuring out those features of work, not being clear and not be able to communicate with other trade partners, responsible parties, it's going to cost in delaying schedule.

And of course, there is other unknowns that may impact the schedule. But what we wanted to highlight here is we know that the schedule is the biggest challenge on this project. And it won't be a better time to maximize VDC to support this.

So with all the challenges that we are facing, the site conditions, existing conditions, modular bathrooms, schedules, DPR has established early in the [INAUDIBLE] phase that VDC would support. What are you seeing on the slides gives an idea of in DPR what we are doing with to assist different project phases and needs, from modeling to coordination, estimating, all the way to the [INAUDIBLE] documentation.

So what's highlighted here are the ones that we have been using on this project. But this presentation isn't going to cover all of them. But we'll focus on the ones that make this project unique.

So now we've identified the challenges and aligned on the strategy to leverage VDC. Let's talk about the data and tools that needs to be ready for any of the VDC implementations. So when it comes to renovation projects, one of the key to the success of VDC is to have an accurate comprehensive model of the existing conditions to rely on, because we all know that the [INAUDIBLE] model is not always accurate, especially considering how old this building is.

So the reality capture model is really the foundation of all the model-based workflows like the design constructability reviews, beam coordination, and other VDC implementations. So as soon as the interior demolition was finished, we went there and laser scanned the entire interior of the building. So in order to align the scan data to the model, we positioned the target stickers. As you can see on the image here, we put it on the columns, and then having both the surveyors and the latest scan team capture those targets.

So the server can provide the coordinates of these targets. And then we were able to convert those coordinates to the model coordination system coordinates and then eventually align the skin in our beam model. So one significant finding is that we found out that the actual building column lines has a discrepancy from the design grid lines, as you can see from the bottom left image here, which the gray is from the design. And the blue is from, actually, the center line of the scanned building columns.

So since the building is more like a triangle shape, and the North part of the building has a slightly different angle, we think which is causing the discrepancy. But being able to realize this before installation or even coordination started brought huge value. We avoid a re-coordination, reinstallation, and other field issues down the road. And also, we've been able to create heat maps out of the scan data so that we can visualize the high and low point of the floor.

Another important part of the data is the authored models. Just like most of the projects we've worked on that leverages VDC, a good design and contractors model, it makes it much easier for coordination process and delivers a better result. In addition to that, we've created some other miscellaneous model to assist our workflows like using the Autodesk Revit and Dynamo to create fireproofing models on structured steels, create clearance zones, 3D grid lines, 3D room tags, and so forth.

So those models helps a lot during the model-based coordination meetings. Being able to quickly tell the locations of where we are looking at makes the meeting much more efficient. With regards to the file sharing, all of our models were uploaded and shared with using Autodesk BIM 360 Docs.

Now we've transitioned to [INAUDIBLE], which is a more upgraded integrated tool. But back then, we were using BIM 360 Docs. And it was great having the ability to manage user permissions, uploading and sharing files makes the whole process very smooth.

So that pretty much covers all the data that related to the VDC workflows. The next is the tool that we use. So at DPR, we use a variety of tools to enable our VDC workflows throughout the project life cycle. So on this slide here, we've highlighted the softwares that we use on this project from model authoring that we use Revit, Dynamo, to coordination, then we use Navisworks to view the models, Glue to host the coordination models, BIM Track to manage the issues.

During the [INAUDIBLE] phase, we use Assemble, also Takeoff, WinEst. And then in planning, which we're going to cover in a little bit, visual planning we use the Synchro Pro and PowerBI, P6 in our general construction scheduling, and then SmartSheet in all the VDC related scheduling works. We also use ACC Build, CMIC for our project management platform, and then Seam for viewing the scan data.

Now that we have the data and tools, let's dive into the workflows. So we've done a lot of things with VDC on this project to tackle the challenges. First, we've engaged very early in the pursuit phase. We figured out the site logistics using the 3D models, and then create sequencing and logistic animations to help the team to get to work.

And then knowing that we're going to use the SurePods, we got involved very early in the design stage to assist that process. So we did a virtual mockup by getting a rendered 3D view looking at the guest rooms, the pods, inside the SurePods, focusing on the look and the feel of the design intent. And that allows us to quickly adopt design changes and sharing it with the stakeholders to get their input.

We also help the design to include the modular bathrooms in the layout of the typical floor to make sure everything looks good to avoid redesign. We were able to identify the SurePods framing misalignment, plumbing fixture conflicts, access panel outlets, you name it, during the design phase so that we will have fewer RFIs during construction, and ultimately, help the construction stay on schedule.

And in addition to that, due to the complexity of the detail of the exterior envelope of the building, we did a virtual mockup of the detail of the canopies and other focusing areas. So what we did is we created a virtual mockup model with LOD 400 or more detail and adding all the available information from the design, trade partners, like, shop drawings, information to put together into the model. And if you can see on the image on the top right, that's a section view of the mockup of the canopy.

So with that, we were able to achieve a lot of things like identifying scope gaps, generating RFIs after we did the constructability review with the team of it. And then we were able to use that, generally, to-- it's great to start conversation about the details, the installation sequencing and everything.

All right, so we just quickly ran through the first three of them on top due to the time constraints. But I'm going to dive more into the virtual visual planning and model-based coordination workflows.

So immediately upon realizing the importance of sequencing and the planning of the SurePods installation, the team starting to look into leveraging visual planning, also known as 4D. So we used the two different approaches, the macro approach and the micro approach to see things on different levels. What we wanted to achieve from the macro approach is that we wanted to visualize the sequencing on a higher level, on the floor level, which includes activities like demo activities, new skin, new structure construction, wall framing, the path of the SurePods, most importantly, and everything else, the MEP, everything that may affect SurePods delivery and its movement to inside the building. This allows everyone to visually see what needs to be cleared and coordinated to the path of the SurePods and addressing any logistics and facing issues.

Here's a couple of the key outcomes from this macro approach. One is that we were able to find the best access point for the pods to enter the building. First, we identified a few locations that, potentially, the pods can use to enter the building. Again, we run clash between the SurePods model and the scan data to see if the pods can fit or if there are any clashes, like the one we're showing on the top right.

So that's the access point from the atrium. The floor-to-floor height from the scan data turns out to be fine. The SurePods can fit. However, the new steel support from the design model that we added in is making the window a bit too tight for the past two years. That's just one example.

And what else we'll be able to achieve is that the route that needs to-- for the SurePods, after it enters the access point, and move it to the final location. So that route, we made sure all the MEPs that's already installed at the time will not being in its way.

And lastly, our self-performance team was able to use this exercise to optimize the drywall installation schedule. Like you see on the screen bottom right, the path is in conflict with the wall, which means that section of the wall needs to be left out before the SurePods is installed. So that's the overview of the macro approach of the visual planning for the SurePods.

And then for the micro approach, we were trying to understand on a micro level, what's the typical SurePods installation looks like? And trying to get all the trade partners buy-in and feedbacks on the proper location, connections, and access point on these parts. So , first, we focused on making sure that all trade models of MEP, all the MEP components has a clear understanding that they need to stay higher than the SurePods motion clearance. And then we focused on coordinating the MEPs, making sure there's no conflict, both in the overhead of the SurePods, as well as other locations like the corridors, et cetera.

The last step is then to create the SurePods movement visual to make sure there's no conflict. We've added all activities like the floor leveling, drywall framing, finishes, overhead MEP sequencing to this macro approach, visual planning study. And finally, we were able to make sure there's enough room for the final operations and the final connection to those SurePods connections.

So this process, there are some significant findings as well. One example is that we found a clash between the vertical vent riser and the SurePods pathway. Being able to identify this issue very early allowed the team to strategically adjust the sequencing of the plumbing installation, and ultimately, avoiding rework. So to sum up, both of the macro and the micro approach of the SurePods visual planning was very successful. And it won't be successful without the reliable laser scan data and the model-based coordination, which is another key workflow in this project on the model-based coordination.

So model-based coordination, also known as MEPF coordination, has become a low-hanging fruit thanks to the wealth of the data that's readily available after the model, the latest scan data. But Autodesk software really facilitates all the workflows like clash detection, coordination, visualization, everything. We wanted to highlight here is what you are seeing on the screen is a model-based coordination dashboard the DPR team creates to visualize the status of the BIM coordination process, like the trend of how many issues have been created and closed on the timeline gives a warning when you are seeing issues-- are not getting close as fast as they're being created and which discipline is falling behind on resolving its issues.

So having this allows the VDC managers, and essentially, all stakeholders to make sure the schedule is on track. And then the image on the right is a screenshot of the model in [INAUDIBLE]. You can see each bubble represents an issue that we've resolved during coordination. Gives an idea of the amount of issues that we have to resolve in order to get this building coordinated.

This one, we wanted to highlight the workflows. The last section is the implementations. We wanted to showcase what we were able to accomplish in the field maximizing VDC on this project. Starting with the floor leveling, like we mentioned, the team used the latest game data to create a heat map of the floor. And then we did a cut and fill analysis to quantify the amount of the leveling needed to prepare the floor level for the SurePods.

Also, the use of scan and modeling proactively addresses the floor levelness issue. Led to a very good result, and making it possible for one-time installation. And we were able to significantly reduce the quality issues.

The other implementation here is the exterior framing. As we face the challenging of the exterior framing of the West facade that has a very limited and shared access, the team determined to use a prefabricated approach for the facade framing. It helped us alleviate the congestion and also reduce the safety risks of the scaffolding. You can imagine would need to be installed on that tight alley side.

The team leveraged the latest gain in the model to determine the exact dimension and deviation to create an accurate panel plan. The DPR [INAUDIBLE] performing team also came up with a pattern to determine the most efficient modules for constructability. As you can see on the left image, the color represents different types of panel. And in the middle image, it's showing one of the shop drawings created from the model for a specific type of the prefab panel. And then the image on the right is showing what's going on in the field that we use one of the open floor plates to create an assembly line for producing the exterior panel, including framing, sheeting, and fluid applied error barriers.

With that being prefabbed, the only remaining part is the metal panel system to complete all the facade on the West side. The success was very much due to the latest scanning and modeling by the project team. And that, I will let David to show how the SurePods ended up being delivered and installed.

DAVID STONE: Thank you, Finn, for walking us through the challenges, the data and tools, and workflows. And really, this slide here talks about our planning for the SurePods. And we walked you through a little bit of it earlier.

But if you look at the images on the left, you can see the iteration starting with the atrium access point, which didn't work because of the access with the new steel. The second image in the middle shows an alternative going through the alley, which was very congested. And, really, the final outcome was this option, which was in a narrow end of the building, bringing it up on the side where you see the H on F street, or the crane location lifting it and bringing it into the edge of the building. This was partially also dictated by the timing of the curtain wall being installed.

And as mentioned earlier, there were only three days that we had to load 206 pods onto the four floors that are occupied by the hotel rooms. So with that, this next video that we're going to play for you is a really good walkthrough of the SurePods and the value proposition, as well as our clients point of view.

[VIDEO PLAYBACK]

[MUSIC PLAYING]

- Being able to install the SurePods within the guest rooms really helps to provide accuracy for the construction and really ease that process.

[MUSIC PLAYING]

- The great thing about these pods is that they're all built exactly the same in a shop. So it's predictable outcome every time they come here.

- I think one of the big benefits with SurePods, too, is we were able to do a first article review back in December, a few months before the rest of the production went into it. So we're to go out on site with the [INAUDIBLE] group and [INAUDIBLE], DPR, SurePods, everybody, and look at the pod, confirm the choices that we made. But then there are also some things that when we saw the pod, we realized, oh, this should be a little bit different here or there. We were able to make that change early in the process and be able to carry that through the rest of production too.

- I think from our perspective, it's a huge schedule standpoint, and then also, a cost standpoint too, the fact that you're able to fabricate these somewhere else, from a schedule standpoint, means that you can run this concurrently with all the rest of your work but avoid having all the trades in here. You're able to source the exact same tiles, materials, all over the place. And again, once it's on-site, it's done.

You're able to do a lot of the QC up front. You still do your punch list in the field. But since it's done in a factory, your quality is generally better anyway than doing it in the field. There should be a lot less of those items anyway. I mean, as you're dealing with construction or different contracts or different trades, you have tile from Italy here. If an electrician is coming in there and accidentally damages or chips it, this avoids those questions and challenges of damaging a product during construction.

- Can you talk us through the steps to get the pod set and everything that goes into being ready for that?

- We rough in all the overhead MEP, everything that's from nine feet and up. And then we get it ready in a position where the connection points are all in one location that we can reach from an access panel. We'll come in, unwrap the pod, pick it up, and set it in place. This move alone, which takes about 10 minutes, will automatically get us 50% through the schedule of the room.

So now that we have the constant, which is the SurePod from every room, we can predict how much material we need and save on the waste that would generate from one project to another. So all we have to do is make sure that we set them all in the designated location, and then we can lay out the rest of the room knowing that each one will be exactly the same. One point is the finishes are exactly the same in every pod inside, but also, the surrounding finishes, now we can predict where they go.

So just today, we installed the tile and the entryway here. And you can see, we snapped the line of where the tiles would stop. And we can guarantee now in every room, the line is going to be the same with respect to the pod. This takes out the tolerances and the inconsistencies in the field.

- I think those are all great points. And it really goes to show how we're doing that for the betterment of the job as a whole because it not only helps our trade partners be able to forecast the amounts and eliminate the waste and improve their quality. It also works really well for our client to ensure that we're thinking ahead and we're planning ahead and making sure that we figure out these issues early on and forecast that for the betterment of the schedule and the job.

- Bathrooms are really the hardest and most time-consuming things to build in a hotel room anyway. To be able to have that done, again, offsite and dropped in, it's a huge benefit.

[END PLAYBACK]

DAVID STONE: Great. So, hopefully, this video really did a great job of illustrating the benefits of the SurePods or the modular construction in general. And what you're seeing in these images here are some of the same images you may have seen in the video, the one on the left showing one of our SurePods installed with an unfinished space.

And then the image on the right, which Finn spoke about the exterior panels on the alley side, in this image, it's showing in progress. It's showing the metal panels applied on top of it. And you can get somewhat of an idea of this alley space being fairly tight. And this alley space was access to both our project's parking garage as well as the adjacent building. So it was a very active alleyway.

And then with that, this last picture here is just a way for us to show you what the project looked like post-construction and prior to construction. So this is the summary of our project. One of the interesting things to add to our conversation here today is that one of the drivers to renovate the building and use the existing structure is the analytics that was done to be able to offset the CO2 emissions by capturing the existing structure and not having to demo and rebuild the entire structure.

It also helped us that we did the prefabrication and modular by offsetting lots of the intensive labor that would happen on-site. It improved our quality for those scopes of work, and also, helped us with the safety aspect because you didn't have as many people walking on your job site. So again, kudos to everybody in our team.

Thank you, Finn, for helping us with presenting our workflows. And with that, we're going to wrap it up and say, thank you.