All posts by Mike LaRue

Prefabricating 75,000 lb. Tanks

Prefabrication is a schedule saver that reduces congestion and promotes safer work at jobsites. On a current jobsite, prefabrication was used on a grand scale. The specifications for this prefabrication job included four tanks and five alcove walkways for our food client.

With limited space and large items, the JP Cullen team prefabricated these tanks and alcove walkways adjacent to the active jobsite to avoid unnecessary congestion. To comprehend the size of the tanks, one tank weighed in at 75,000 lbs. and had a holding capacity of 105,670 gallons. In addition to these massive tanks, the five alcoves were prefabricated with structural steel, MEPF systems, and insulated metal panels.

A prefabricated alcove is resting on top of the Goldhofer remote controlled trailer.

Putting together both the tanks and alcove walkways on the ground greatly reduced the amount of work that could have been done 65’ in the air where these items would have gradually been installed piece by piece. After these items were prefabricated, the team used a Goldhofer remote controlled trailer to transport these items to the install location. Within six days, the JP Cullen team put together and installed these items safely and efficiently. 

Tough jobs call for smarter and safer solutions. Learn more about JP Cullen’s prefabrication and how it can benefit your next project here.


Prefabrication wall at the Milwaukee Bucks Training Center

6 Ways Prefabrication Can Benefit Your Construction Project

Prefabrication is not a new concept to the construction industry; it has been around for centuries.  However, it has reinvented itself with the growth of Building Information Modeling (BIM).  BIM enables the increased use of prefabrication, making it more feasible to implement on projects.

Read on below to find out what prefabrication is and the six ways it can benefit your next construction project.


Prefabrication is the assembly of building components away from the face of the work.  This includes items such as:

  • structural steel decking
  • towers
  • chimneys
  • structural wall panels
  • weatherproofing
  • brick ties
  • brick arches
  • bond beam lintels
  • dentiles
  • roof decking
  • tilt-up
  • MEPF systems
  • electrical rooms
  • server rooms
  • interior wall panels

According to a study published by FMI/BIMForum in February 2017, the construction industry is still struggling to adopt prefabrication at a broad level.  It is not used by many in the industry, mainly due to resistance to change and the initial investment to develop the process. Most companies are prefabricating less than 1% of their work – at JP Cullen 35% of our work includes prefabrication.


We have seen an average of 10% savings in cost, 25% savings in schedule, a 5% reduction in re-work, increased safety, and an average of 16% decrease in hazard reduction cases.  Coordination is improved as is site cleanliness and organization.  Owners are getting a better, higher quality building in terms of how it is built.


Improved Safety
We have seen an increase and improvement in safety. The most obvious is the reduction in fall hazard exposure since we can do more of the work close to the ground. On average we realize:

  • 16% reduction in structural steel fall hazard exposure
  • 17% reduction in MEPF racks fall hazard exposure
  • 50% reduction in wall panel fall hazard exposure
  • 50% reduction in roof decking fall hazard exposure
  • 16% reduction in masonry arch fall hazard exposure

Increased Quality
Prefabrication allows us to work in a controlled environment, utilizing standardized processes. It also allows us to set up standardized checks all the way through assembly allowing us to build better, higher quality buildings.

Schedule Savings
We have found that prefabrication typically has 25% schedule savings. Having knowledge of how long each component takes to design, fabricate, and deliver is a key element in these savings. This allows us to turn the building over to the owner sooner, enhancing the revenue stream to the owner; since the quicker they have use of their building, the quicker they can start generating revenue.

Organized Workplace
There is a reduction of labor on-site and indirect labor working on building has reduced congestion and eliminated labor shortages.

Cost Savings
Fewer errors and greater efficiencies translate to an average of 10% cost savings for our clients. When combined with BIM, change orders are significantly reduced with the use of prefabrication.

Less Waste
Our project teams are always looking for ways to streamline a project, standardize our work, and define repeatable tasks. Prefabrication allows us to do that. It provides a controlled environment in which to work, where the weather does not affect us and we can work at an ergonomic height. It also allows us to design efficient assembly processes and material flows specifically suited to the project. Prefabrication provides precise measurements, preventing material waste allowing unused materials to be recycled.

Virtually any project can benefit from prefabrication no matter the market and can range from small repeated units like door trim assemblies, up to complete modular rooms with furnishings in place prior to installation.


To learn how prefabrication can be used on your construction project, contact Mike LaRue, JP Cullen’s Prefabrication Manager, at or 608.777.0100.  You can also check out our video and website for more information.

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Ingraining Prefabrication Into Everyday Work

As part of JP Cullen’s Lean Process Improvement culture, we are constantly looking for ways to do things faster, easier, and more efficiently. The internal steel stud walls were identified as an area where we could make significant gains using prefabrication. The two 115K SQFT office buildings in the Madison area that we are leading were prime candidates to implement panelized metal stud walls as a way to improve building schedule and quality by internalizing a process.2

Trialed on an earlier project, the steel stud wall panels provided a host of benefits, including improved efficiency and ergonomics for JP Cullen’s carpenters.  A restructuring of the traditional build sequence allowed us to build the walls without the congestion of other tasks being performed in the same area. This was a good starting point, and there was a great amount of potential in the process.3

Planning is the most critical part of any of JP Cullen’s prefabrication efforts. Each panel was modeled in our BIM software to minimize errors before drawings were provided to the crew. By focusing all efforts on one floor at a time, the crew was able to get a typical 120′ office floor ready for drywall in just 6 days.

Over 20,000 linear feet of walls were panelized between both of the buildings in just 10 weeks, an impressive 35% reduction in schedule. Crew composition was a hidden factor on this project. The steel stud panel crew’s relative lack of experience (nearly half were apprentices) may seem like a disadvantage. However, the crew first competed with, and then exceeded, the pace of work of the experienced stick frame crew. By training apprentices across the company on the wall panel process before moving them to the stick frame crew, JP Cullen will be blurring the line between traditional building and prefabrication. This will ingrain prefabrication not as something new, but as the way we do business.4

JP Cullen has found that prefabrication is a good fit with our “Living Lean” philosophy; it emphasizes quality, safety, decreased building time, and cost reduction though lean methods.

If you have any questions relating to prefabrication or to see if this approach may be incorporated into any upcoming projects for your company, please feel free to reach out to Mike LaRue, Prefabrication Manager at JP Cullen.


 Two of the projects that JP Cullen has recently had the opportunity to lead were a pair of multi-level office buildings in the Madison area.  The challenge to the team was to deliver the two 120K SQFT buildings on a shortened time table in order to meet the needs of the client.  The JP Cullen prefabrication team determined prefabricated MEPF systems were a likely candidate to accelerate a critical part of the building schedule and meet the project deadlines.

An ambitious project from the beginning, the modularized MEPF system was proposed early on in the projects as a way to decrease the amount of time spent constructing the buildings.  MEPF modules are a combination of all of the various systems, blocked out at regular intervals.  The hallway MEPF modules built for the projects contained all Ductwork, Electrical, Fire Protection, Hydronic Piping, and Plumbing systems that run down the corridors of the building.  The MEPF modules were built ahead of time on the ground in an offsite manufacturing center, strategically laid out for optimal efficiency with each trade contractor doing their part. The MEPF modules were then delivered complete to the build site where they were installed and connected in a matter of minutes.  JP Cullen and the projects’ MEPF contractors developed a model that not only decreased time spent in the building, but decreased costs as well.


Each MEPF module was fabricated at the offsite manufacturing center in an assembly line environment to increase productivity.  The systems were tested and insulated before they were installed into the MEPF module.  This process improved quality while making field operations much more efficient.  This also allowed the shop to detect and address any quality issues before the MEPF modules were shipped to the field, reducing time spent in the field by ensuring proper fit and function.  Producing the MEPF modules in a manufacturing environment allowed a test fitting of the systems before field install.

Safety is a priority at JP Cullen.  Building the MEPF modules in a controlled environment allowed the MEPF contractors to perform 60% of their install work at ergonomic heights on the ground.  This reduced exposure to fall hazard by 60%.  The ergonomic heights also reduce wear and tear on the body by minimizing bending and overhead work.


With the majority of the work completed in a controlled environment, there was a substantial reduction of work to be done in the field.  The first building was installed in just under 6 days.  The second was installed in less than 5 days.  197 MEPF modules were installed in both buildings, which added up to almost 32,000 feet of materials, and comprised roughly 60% of the hallway mains.  This was a massive amount of material to be installed by a small crew in slightly more than two weeks between both buildings.  Listed below is the total amount of modularized materials for both buildings:MEPFBlogGraphicimage4
The speed and completeness of the MEPF modules greatly decreased the time required for the remainder of the MEPF systems to be installed.  With about 60% of the congested hallways installed in such a short time, the crews could concentrate on the branch lines, which were standardized by the MEPF contractors.  Standardized systems reduce material handling problems, leading to more time spent at the face of work, and less time spent combing the building for parts or tools.  The MEPF modules also decreased the amount of material on the floor that needed to be worked around, further increasing the efficiency of the remaining crews by reducing congestion.  The result of these improvements brought by the modularized MEPF system included a 50% cut in task duration.


A critical tenant of the culture at JP Cullen is the Lean Approach, which was the cornerstone of the modularized MEPF system.  At its core, the MEPF modules took many parts of many different systems and made them one complete component to be installed.  The MEPF modules were then delivered “Just in Time” to the building, where they were immediately installed.  This streamlined efficiency reduced wasted activities, like sorting materials or constantly rearranging them to accommodate other trades, while improving quality by minimizing the potential of installing the wrong part.

JP Cullen has found that prefabrication is a good fit with our “Living Lean” philosophy, it emphasizes safety, quality, improved building delivery time, and cost reduction though lean methods. If you have any questions relating to prefabrication or to see if this approach may be incorporated into any upcoming projects for your company please feel free to reach out to Mike LaRue, Prefabrication Manager at JP Cullen.


A few of the latest projects the JP Cullen team has been leading are structural steel erection projects in the Madison area, which involved the use of prefabrication on the jobsite. Due to some unavoidable challenges early on in the foundation portion of the project, the team knew they had to make a comeback to keep the project on schedule.

The use of steel prefabrication was the answer as the 228K SQFT project was brought back on track, allowing the team to not only get back to the intended schedule, but actually gain on the timeline. Prefabrication is not commonly utilized in the construction industry, mainly due to resistance to change in combination with an initial upfront investment by the company to develop the process. After the process is developed, as JP Cullen has successfully accomplished, a client can expect to see the project schedule bound ahead along with an increase in quality of the craftsmanship due to a majority of the work being done in a controlled environment versus at the face of the work.

A major portion of the prefabrication process for these projects involved the iron workers, who had the opportunity to sequence out the delivery of their structural steel to the jobsite. This sequencing allows the team to make sure pieces arrive in the order being built to the project, which in turn avoids the crew being inefficient and searching for their needed pieces by the industry standard truckload delivery. When a project requires over 255 tons of steel, it’s crucial to plan ahead and sequence the work to stay on schedule.

Below shows an example of how many steel components went into each building:

• Building 1:
o 210 pieces structural steel
o 616 bolts (detailing)
o 5,298 shear studs
o 27,000 SF metal decking

• Building 2:
o 201 pieces structural steel
o 644 bolts (detailing)
o 4,511 shear studs
o 24,000 SF metal decking


The team purchased column tops and set up a test fixture. After a couple of trials they developed a plan and process to prefabricate the structural steel panels on the ground. A special concrete fixture was built for each building to fit the specs of the 85 total panels that could be built at ground level. The ground level fixture squared the panels as they were built, naturally forcing the columns to be plumb.  This ensured a quality building without the need to plumb each column separately.  The time needed to plumb each column was effectively taken away from the building, freeing up more time to set panels.


Prefabricating the structural steel panels allowed the team to fly several pieces of steel into the building all at once, leading to huge schedule savings, 4 weeks per building, in a time critical portion of the building process. Due to this process, the panels were more complete when they were installed compared to a traditional build. The metal decking, shear studs and even the receivers for perimeter fall protection posts were attached while the panels were on the fixture. Not only did it save time on these activities later in the process, but it was safer to detail the panels on the ground.


Safety is a major factor during every building project – especially during the steel erection phase. The team reduced their exposure to fall hazard by 16% by working off of the custom ground fixture, which was less than 6 feet off of the ground versus what would have been 44 feet above ground. Workspace congestion was decreased and efficiency increased as fall protection gear was not required at this height, which reduced fatigue and increased productivity. With all tradespeople working on the ground versus above, only a few lifts were needed on site which further reduced congestion. An additional benefit to working from ground level is the ability to double check the quality of work. It makes quality control a lot more measurable when you’re on the ground versus over 40 feet in the air.

An additional challenge facing the project team during this time frame was the shortage of ironworkers available for the site. Due to the prefabrication of the steel on the ground, the team was able to meet and pull ahead of the intended schedule with fewer workers than a typical project of this magnitude. Normally the process would have been to set the columns, then set one or two pieces of the beams at a time. This new process allowed a simultaneous build of the building with fewer people – in a more proficient manner. By prefabricating structural steel panels, the iron workers onsite reduced the work done at the building itself, increased safety and productivity, and balanced manpower more efficiently.

JP Cullen has continued to incorporate prefabrication into many other phases and areas of work onsite due to the success of these projects. If you have any questions relating to prefabrication or to see if this approach may be incorporated into any upcoming projects for your company please feel free to reach out to Mike LaRue, Prefabrication Manager at JP Cullen.