Lark leads the way in virtual construction using, fully integrated 3D, 4D and 5D BIM technologies and workflow to control the project from design through to completion.
A fundamental reason why Lark has taken the initiative to be at the forefront of BIM technology is to maximize the value that BIM brings to Owners. We call this True BIM. It starts with our in-house capability to produce accurate Construction models, building the model in detail floor by floor and adding construction means and methods. We use schedules within Revit to monitor the design development and Trimble Vico software and processes to control 4D (scheduling) and 5D (costs). Vico is the most integrated BIM software and any changes to the model automatically update the impact on cost and schedule.
The “As-Built” BIM model at a Level of Development 500, is populated with relevant building component information such as product data, O&M manuals, cut sheet specifications and warranty data.
During Design Development the Architectural Revit model will be used for program validation and will be developed from LOD 200 to LOD 300. A Model Progression Specification (MPS) will outline the modelling protocols in detail. Included in the MPS will be Revit Family naming conventions for seamless downstream use in 4D and 5D processes using Trimble Vico software. The LOD follows the guidelines set out in AIA Document G202 – 2013
The Architect’s model will be handed on to the Structural Engineer, to verify the structural elements. The Structural model will then also be developed to LOD 300. By that stage the MEP design should be complete and those models also produced to LOD 300. These are data rich BIM models, not just visual 3D representations of the building. The common programs used are Autodesk Revit. In addition to the design models created by the design consultants additional software may be used for Energy modelling and Structural analysis.
From Design Development to the completion of Construction Documents the models are continually compared for clash detection to assist with coordination. This clash detection process is initially run in Revit, and subsequently using Trimble Vico software. In combination with hard and soft clash detection, Lark also has an established best practice for Constructability Analysis. By building the project “virtually” in Revit using 2D drawings for reference, we are able to conduct constructability analysis, identify missing information and add means and methods. This is our Construction model. On a number of projects, we have shown to significantly reduce the number of RFI’s and changes during construction.
We log and track every clash and constructability issue until each is resolved. During construction we use the 3D models to enhance communication, and as a reference for dimensions and elevations. In congested ceiling spaces we often produce colour coded construction drawings for Mechanical and Plumbing layout, using accurate information from the fully coordinated Mechanical model.
LARK uses Vico software to produce a “Flowline” schedule for production planning and control. A flowline is a graphical representation that shows the movement of crews through locations. This is a Location Based Management System (LBMS) that uses Line of Balance theory to optimize work flow and productivity. The schedule is driven from the 3D model quantities and our proprietary database of production rates, and so any changes in the 3D model will be automatically reflected in the 4D schedule.
To achieve increased productivity, LBMS plans for continuous work for resources; the completion of work at a location before leaving that area; and the elimination of interference of trades in the samephysical location. In LBMS it often makes more sense to delay the start of a task to allow for continuous work, than to start in unproductive conditions and work slower. Starting early and working slow because of interference will result in more inefficiency than starting later and working fast. The focus of LBMS is managing the completion of locations instead of the commencement of locations. This methodology has shown to increase productivity significantly.
Vico is not only a superior planning tool, but is also highly effective in controlling the schedule during construction. Actual production data is captured every few days and the schedule calculates a forecast based on the actual production trend. This allows the team on site to be proactive and to take corrective actions very quickly if needed.
5D QUANTITIES AND COST MANAGEMENT
We use Vico software to generate accurate quantities from the models by location to support estimating and scheduling.The quantities are extracted directly from the 3D model and so any changes in the model (changes in design) are automatically reflected in the quantities and cost plan. This helps with cost management during design, and having accurate quantities also helps reduce waste during construction.