Model Progression System (MPS) can improve the building information modeling process

MPS is a suitable language for owners, designers and builders to identify each component and task in the building construction procedure. The MPS establishes the communication between the architect, the design team, the estimators and programmers and directs the procedure of progression of the design. It brings all the information about the building: which components must be modeled and with what level of detail the components are modeled, estimated and programmed. Presents the efficient schematic to the project stakeholders. It can be referred to as a written checklist that grew from a very representative level of detail to a high level of detail based on 3D geometry, cost, and time. Predictable cost and schedule become increasingly precise as the level of detail increases throughout the design procedure.

It arises from the need to define the representations of building elements in a BIM (it is possible to use a BIM for many purposes: costing, programming, performance simulation, code verification and visualization, etc.) and a framework for the accuracy and suitability of BIM. for specific uses. MPS methodically classifies project data for each control point in BIM practice.

Webcor Builders partnered with Vico to develop the concept and present it to the technology subcommittee of the AIA California Council’s Integrated Project Delivery (IPD) Work Group. In order to extend the usefulness of the MPS, all the opinions of architects, contractors, engineers, subcontractors, owners and software developers were taken into consideration. The AIA National Documents Committee approved the approach, provided further development, and included it in the new E202, an exhibition, in the fall of 2008.

In addition to its three-dimensional demonstration, a large amount of information can be associated with an element in a BIM. Information can be obtained from a variety of people. For example, while the architect generates a three-dimensional illustration of a wall, the GC may offer a cost, the HVAC engineer a U-value and thermal mass, an acoustical consultant an STC rating, etc. To deal with this variety of input, the AIA Documents Committee devised the concept of a “Model Component Author” (MCA), responsible for the formation of the three-dimensional representation of the component.

Level of Detail (LOD).
At the core of MPS are the LOD definitions. They are representations of the steps, in the course of which a BIM element can rationally progress from the lowest level of conceptual estimation to the highest level of representation accuracy. Five levels were enough to define the progression from conceptual to built. However, to assign future intermediate levels, the levels are named 100 through 500. In a real sense, the levels are as follows:

100. Concepts

200. Approximate geometry

300. Precise geometry

400. Manufacturing

500. As built

At LOD 100, the cost of a foundation structure is a standard $30 per square foot and the building requires a foundation structure. Neither dimensions nor production processes are recognized at this level of detail. In LOD 200 the approximate location and indicative dimensions of the foundation elements. In LOD 300, the results of the structural analysis indicating that the actual dimensions of the foundation elements are verified are acknowledged and a decision is prepared on the production system to be used (cast-in-place or precast?).
As the design scales, various model elements will advance from one LOD to the next at different rates. For example, in conventional phases, most elements should be at LOD 300 by the end of the CD phase, and many will move to LOD 400 in the shop drawing procedure during the construction phase. Some items, such as paint, will never be used beyond LOD 100, meaning the paint layer is not actually modeled, but its cost and other properties are tied to proper wall assembly.

With MPS, moving from one project stage to the next is transformed by increasing the level of detail in one or more sections of your model specification. The concept of ‘Owner’ allows for the successful management of the work necessary to complete the required work. Identical and repeatable, the MPS is re-implemented across multiple projects (since each component is unmatched, the progression of specificity remains largely the same).

Summary of MPS functionality:

o Define a “purpose-based model” to include items for estimating and scheduling
o Create a resource-loaded schedule by location that contains all methods and resources
o Design a flowline schedule based on a model with the estimated data extracted from the model
o With the schedule loaded with costs, you can create cash flow diagrams for the owner
o With location-based schedule and control chart connected to cost data, checking schedule status becomes an easy task
o Plot planned versus actual progress on the EVA curve, highlighting schedule performance indicators

With the BIM MPS application exceptionally useful for any project, the depth of collaboration at IPD makes some sort of organized approach like this essential. With this in mind, the MPS is developed to address two principles of IPD:

1. The requirement “that the phase results – milestones and deliverables – be succinctly defined” so that team members “can identify with the level of detail with which they should be operating and what decisions have (and have not) finalized”.

2. The idea of ​​assigning tasks “on a best person basis, even when that differs from traditional role assignments” (Integrated Project Delivery: A Guide, p. 13)

In an IPD project, with tasks assigned on a “best person basis,” handovers are likely to occur at various points in the design process. For example, the mechanical subcontractor may take over as MCA for the ductwork during the detailed design phase.

References:
http://www.aecbytes.com/feature/2008/MPSforBIM.html