Creating the 3D constructible model for a six-story, wood-framed building
Can you build a six-story, wood-framed building in SketchUp? Yes, you can. Just ask John Brock, custom home builder, and designer. He’s been in the industry for over 30 years and uses SketchUp as his go-to software tool. He builds highly detailed models - down to the stud, which has inspired him to create different SketchUp extensions to help with his construction workflow. He dives deep into his workflow and how he implements it on a new multi-family residential project in Canada.
A lot of the SketchUp community knows you and your work from the many presentations you’ve given, and the work you have done. Could you give us a rundown of your business?
With my construction consulting company, Constructability3D we support builders around the US and Canada by modeling their structures in detail based on their 2D architectural, structural, civil, and MEP drawings in order to avoid issues or clashes. We issue a Constructability Review, detailing our findings. Invariably, this ends up saving my clients thousands of dollars on each project. Essentially, we are building their structure before they do, so if we have questions, they will have questions. For example, we work with their truss vendors and import the actual truss models for their projects into the 3D model. More often than not, we find significant issues before they order them and become expensive mistakes and delays. We have become a “Pre-Construction Project Manager” for most of our clients, hosting pre-con meetings via screen share. The architect, structural engineer, truss vendor, and lumber salesman will all join the meeting and I fly them around the model in SketchUp. This includes Scenes for all phases of construction, from the footings, foundations, and rebar, to the floor systems, wall framing, and roof framing. At the beginning of 2019, my book “SketchUp for Builders” was published with Wiley Publishing and I detail my workflow in the book.
John showing off his book, “SketchUp for Builders”.
You recently took on a major multi-family building in Canada. Can you tell us a little bit about this project and how you got started with it?
Duane Addy who is a colleague and fellow SketchUp enthusiast works for a builder in Calgary, Alberta, Canada who was developing a $320 million project. He contacted me to see if I would create a constructability model for a six-story, timber-framed building within this development. Addy had been trying to transition this company into a full virtual design and construction workflow, and the constructability model would play a major role in bringing that vision to life. Three high-profile penthouse units that Addy had designed all required interior design drawings as well as a full rendering package and blackline floor plans for touchscreens.
The new six-story, timber-framed structure in Calgary.
Constructing a six-story, the timber-framed structure is challenging! What are some challenges or obstacles that someone might face constructing a building like this?
The units within this building do not “stack” as is typical of multi-level residential blocks. This led to a lot of complex engineering and framing to make the design work. The detailed model pointed out numerous clashes, hedging off some potentially major problems.
Other big challenges included ensuring appropriate fire-ratings, building in allowances for shrinkage in the timber, and managing considerable changes in wall thickness and stud configurations as the floors went up.
Tell us a little more about the project goals, your role, and the timeline?
This building design and construction started in January 2019 and will take approximately 9 - 12 months to complete. Of the many project goals in this project, the main one was efficiently constructing the six-story, timber-framed structure within the estimated timeline. Our role and goal in this project included creating marketing materials, providing interior design drawings for the penthouse units, and building the full Constructability 3D model.
Some of the marketing materials consisted of blackline drawings using SketchUp and LayOut and high-end renderings using SketchUp and Enscape.
Using SketchUp and LayOut for blackline, 2D drawings.
High-end renderings with the help of Enscape and SketchUp.
Were you able to save them time and increase efficiency using SketchUp?
We saved both time and money on this project by building the exact digital representation of the building prior to construction. When I built the representation, it instantly identified clashes and issues unseen in 2D drawings. The results were significant enough that we have just been hired to build a SketchUp Constructability3D model for an even larger six-story building in the same development—over 130,000 square feet!
We use this process routinely to help save our clients thousands of dollars and lots of lost time fixing mistakes!
Since you are remote, how do you use SketchUp to work with the team in Canada?
During the review process, I host several screen share conferences, where I fly around the model pointing out issues. These meetings typically include senior project managers, field staff, engineers, architects, MEP consultants, and many others involved in the project. The builder has multiple licenses of SketchUp, as well as trained staff, so I provided them with the final revised models upon completion.
Did they find the screen shares of the model useful? And would you recommend this type of presentation for others in construction?
Absolutely! Clients get great value from the screen shares in the comfort of their offices. It also cuts out travel time and cost. Using Scenes in SketchUp that are set up by construction phases enables a quick walkthrough of each phase: from the foundation, framing, and floor systems, through to roofing. I navigate through the model so they can just view it. I fly around pointing out all of the issues and they can follow along on my Constructability Review PDF I send them. Using my Issue Tracker extension to tag items means that I can easily print out a branded, graphical report showing the issues along with a description of the issue.
What was your workflow in SketchUp for this project?
My workflow is pretty consistent with all of my constructability jobs; this one tested the bounds of my SketchUp file size, so I had to work at keeping the model as lean as I could. “Lean” is not my strong suit, as I even model joist hangers!
My typical process is to import all of the floor plans for the project, using my PDF Importer extension. I import the PDF and scale it, referring to known plan dimensions. The cool thing about PDF Importer, versus importing a CAD file, is that you can see all of the text. So, when you are adding windows and doors, you can see the sizes versus constantly referring to the drawings, which I keep on a large monitor. Starting with the Main Level Floor Plan and centering it at 0,0,0, I then choose a common alignment point like a corner of the building consistent with each level and then create Guide Points going up and down. For example, I go from the main floor subfloor or slab up the wall height, like 9’ 1-⅛”, then from there I go up the depth of floor system, like 14” TJI’s (Trus Joist I-Joist), from there I go up ¾” for subfloor and so on. This creates a “storey pole,” as my builder peers would understand. I then group these guide points and lock the group so “deleting guides” will not wipe them out. Once I have my storey pole, I bring in each floor plan and snap them into position. A quick top view, or parallel projection, allows me to see if any of the floors do not align properly. You would be amazed at how often drawings do not match from floor to floor and are not caught until too late in the construction phase. Once I have all of the floor plans imported, I put them each on their own layer to control visibility. Then I start from the footings and foundations up to the slabs. The floor plans are sitting directly on top of slabs and subfloor, just like chalked wall lines, so I simply model the walls on top of the floor plans using my Framer for SketchUp plugin. I refer to the plans to make sure all plate heights are correct. When I get to a floor system, I either model the joists or import floor trusses, or a combination of both. This is the same process for the roof. If the structure is stick-framed, I model the rafters, and/or import roof trusses. Afterward, I sheath the roof. All of my models include scenes, so you can easily scroll through the construction phases. As I encounter issues, I simply place an Issue Tracker, on the item, which captures a snapshot of the image and allows you to enter details of the issue. At any time, you can view the report and send it to stakeholders. You can also edit the report to include more colors and graphics to be sent as a branded PDF to clients. And this can all be done inside of SketchUp!!
Catching those issues before they become costly mistakes with Issue Tracker.
In addition to SketchUp and your self-developed extensions, what other software tools support your workflow?
I used Trimble Connect to share models with clients and they used the free SketchUp Viewer app to view models in the field on their mobile devices. I recently got a demo of the Trimble Total Station, where we staked out a new house and got topos. Very cool! I want one badly, but have to save up for that ;)
Side note: Trimble Total Stations include land surveying equipment and total station solutions to meet optical and conventional surveying needs. Check out more information about these stations.
Video of the Trimble Total Station
Do the building contractors work off your models in the field? If so, how?
Yes, routinely, although it’s important to clarify that my models absolutely do not replace working drawings. Working drawings rule as my models are simply a visual guide throughout the process.
Do you use LayOut? If so, what does that look like in your workflow?
For this specific project, we used LayOut to generate the interior design drawings for the penthouse units. In addition to using LayOut for generating construction documents from our SketchUp models, we also use it to generate presentations.
Using LayOut to communicate the penthouse plan details.
For this project, in particular, it was two-fold in that we had the full constructability model for the entire building, and then we had the individual penthouse models that would be used to generate the interior design drawings and renderings. Our process utilized LayOut to manage the construction process. Here is a little insight into that process:
Addy roughly designed each penthouse.
My team developed the initial model for each penthouse design.
Addy took those models and worked internally to build up the final material selections and bespoke items that were being designed on the fly at the Calgary office.
Addy handled the constant model changes and finalized it from a design perspective.
I reintegrated the file back into our LayOut files and republished them for a final review.
Once finalized, the client received the files and managed them for rough-ins and finish details on site.
Addy and I have a long history of working together so we were able to come up with a process that worked for these multi-million-dollar penthouses - one was valued over $3 million dollars!
What are some of the benefits of using SketchUp in a project like this?
I have found that the big players in the CAD software world can generate great drawings and models, but I do not believe most designers utilize or have time to create much detail (models), which is why it is usually left up to the builder to “figure it out”. With only 2D visualizations, SO much gets missed. As a builder myself, I am solely focused on constructability and working out issues ahead of time. The benefits are numerous. For example, when I combine architectural, structural and MEP elements in SketchUp, it enables me to see that there is a plumbing stack coming up a wall with a big beam directly over it - how is that going to work? With the model, it jumps out at you instantly!
Catching issues before they become costly.
Were you able to catch any issues with the constructible model before the team started building it in the field?
Absolutely! There were numerous issues discovered in advance. Unfortunately, on this project, I was not hired until construction had already begun, so a lot of it was “last minute” or in some cases, materials that were already ordered were affected. This building had several structural steel portions and moment frames that I was able to model in full detail. This allowed me to point out lots of pesky items, like bearing plates sticking out past walls and affecting floor coverings. With my models, they were able to get the engineer to re-design numerous plates before ordering.
Using the structural steel model to pinpoint issues before the build.
We hear that SketchUp has a hard time keeping up with in-depth projects like this. Was that your experience?
Indeed my models can get sluggish, because of all of the details that I include. Even the 2D floor plans can considerably bloat the files. Paste-in-Place and Component Reload are handy tools native to SketchUp that can help speed models up. Other tricks that helped included making each unit in the building its own component and SketchUp file. When I need to edit a unit, I can edit the individual file and then reload it in the big model. I also routinely copy items I am working on and paste-in-place into a clean file, make the edits in a clean, faster file, and then copy and paste-in-place back into the big model.
Diving into John’s workflow: editing within an individual unit.
What are some of the extensions you used on this project?
Aside from my four plugins (Estimator, Framer, Issue Tracker, and PDF Importer), my main plugins are Profile Builder, ThomThom’s Solid Inspector and Selection Toys, and TIG’s Mirror.
Any tips for others in the construction industry trying to use SketchUp?
Wow, good question. I HOPE that the industry will progress and use tools like SketchUp.
I always say, SketchUp is a great design tool, but it is also an awesome BUILDING tool.
Even if the builder is trying to figure out a single building detail or how something goes together, they can easily model it in SketchUp. Experienced builders know exactly how to build things and SketchUp gives you the freedom to create any geometry and apply textures to look like the actual product and move, and rotate as needed. I say, start with a simple building project or portion of a job, and practice. Also, watch a lot of YouTube videos - that is how I learned! There are some great teachers out there giving their time to show tips and tricks.
Also, I have a great resource website for professionals in the construction industry. This site has an “ask the expert” section where people can ask me and the rest of the team any questions they might have.