BIM-based Multi-Trade Prefabrication

A Project Management

Case
Study

Since the introduction of BIM, the construction industry has looked at many ways to use the software to increase efficiency and decrease time needed for a project.

Given the current lack of skilled labour, one area of interest has been in using the software to help modularize construction.

Several studies have looked into the possible benefits of using BIM to aid in modularizing the construction site.

This case study looks at several of these projects that used BIM to modularize construction and compares their results with other studies attempting to do the same thing.

Virtual Design and Construction

Using BIM to turn the job site into a production factory

Conventional prefabrication technologies focus on single-trade prefabrication, such as precast concrete products, facade panels, and window frames

Conventional design management can lead to inefficiency because of worker overcrowding and shared material stocking.

Coordination

In the first coordination step, the elements of each trade are relocated, and the interference between trades is eliminated.

Re-Coordination

In the recoordination step, fine modifications are made in addition to eliminating the interference with the trades (ie: structural framing) to connect each element to the specific trades

Conventional Management

Various trade activities in the conventional method may overlap because the relationship between the activities was usually start-to-finish

MTP Management

In MTP, MEP trade tasks can be executed either in parallel with or before other trades such as concrete pouring and curing

Why?

Prefabrication was initially applied in the construction industry to reduce cycle time and costs.   As time went on, it became very useful improving construction quality, reducing waste and carbon emissions.

This project pictured above involves various components and multiple MEP trades  using general corridor MEP (see below) racks that can be used in various types of buildings.

 

Conventional Wisdom

  • MTP may reduce time, but increases costs
  • MTP increases transportation costs of moving materials to site
  • MTP may require specialized equipment for installation
  • While single-trade prefabrication can be effective, MTP adds to much complexity

In Actuality

  • Minimized worker movement (i.e. moved meeting area closer to work floor)
  • Design of manufacturing area eliminated the need for ladders or lifting equipment
  • Reduced the need for support workers
  • Reduced worksite interference among trades

What Did We Learn?

  • MTP with BIM allows for materials savings through bulk purchases
  • Productivity predictable increased using MTP, mitigating initial lower productivity
  • MTP yields improved quality and reduces accidents
  • The process reduces time needed reducing managerial and administrative costs
  • Although MTP increases design time, it reduces the skill level of workers required often lowering wages by 80%
  • As trades/workers become familiar with 3D scanning and BIM-based site logistics, initial productivity will increase.

Bud Clark Commons

The Apartments at Bud Clark Commons offer 130 studio homes that serve residents who have been experiencing homelessness. Nine of the apartments have physical accommodations for accessibility. Part of an innovative center that serves persons who are homeless

Influences on Survey Response Rate

The following factors have been studied as potentially affecting survey response rates.
As to each factor there haye been various research findings as to whether there is a
demonstrated effect between that factor and a higher response rate.

The Living Roof

Pioneered in Germany in the 1960s, a modern “living” or “green” roofing system is more than dumping soil on a roof and planting vegetation. These systems are one of the best examples of a green product on the market today.

Can Technology Save the Construction Industry?

The shortage of skilled labor will be a continual concern of the construction industry especially for the next 3-5 years. Technology will play a key role in developing a new workforce and increasing efficiency in product delivery.