BIM_BM3806(3)_Edumnd Leong_22062012

Diploma in Building

Information Modeling (BIM)

BIM for Construction

Planning & Coordination

(BM3806)

Lecture 02

Edmund Leong

20120518a

BIM for Construction Planning & Coordination (BM3806) – Lecture02 Version 20120518a

BCAA, Specialist Diploma in Building Information Modelling (BIM) 2

Contents

1 Lectures Roadmap ........................................................................................................... 3

2 The Shifting Boundary – Where does Design End and Construction Starts ...................... 4

3 Preparation for BIM Modeling ........................................................................................... 5

4 Typical Information Relationship ....................................................................................... 8

5 Project Information Modeling – Part 1 ............................................................................. 11



1 Lectures Roadmap

In the previous Lecture, you have been introduced to “Challenges and Opportunities” with BIM

for Construction Industry, and an overview to how different types of information can at different

stages in the Construction Phase be utilized. You should understand by now, that BIM

applications can also be used beyond the Design Phase in any building project lifecycle, but

the results from these applications will have different needs’ perspective.

In the lectures to follow, you will be guided on some typical processes to BIM execution for the

Construction Phase. The followings are outline to what will be delivered in the coming

lectures.

- Developing a Construction Model using Design Phase information, to support

construction requirements

- Engaging in BIM-4D to support project construction planning

- Performing Model-based quantities and estimation, and how it can incorporated into

workflow to support cost feedback to project team during construction.

- Expanding on BIM-Model to support Prefabrication processes

All “LABs” in class will be using the following tools

a. Autodesk Revit 2012 (Architecture, Structure and MEP)

b. Autodesk Naviswork Manage 2012

Students are reminded to be familiar with these software at an “Elementary Level” in order to

be effective in the “LABs” workshop.



2 The Shifting Boundary – Where does Design End and

Construction Starts

Traditionally, design and construction have been thought of as two distinct and very separate

phases of a building project. The process was design-bid-build, and the walls between the

phases were viewed as important to maintain impartially as well as providing checks and

balances. But as project becomes more complex, the problem inherent in this approach grew.

So, new project delivery strategies that lower or remove these walls, for example, design-build

and integrated project delivery, are being used today with many successes and advantages

reported.

The key to these new delivery strategies is to get all the stakeholders involved in project

aligned with appropriate processes, as well as risk-and-reward-sharing strategies in place to

enable them to share information and decision-making in a way that improves the overall

project outcomes. Using these delivery approaches, the project team works together from

project inception through delivery and the boundary between design and construction is

greatly blurred.

As the applications of BIM evolve and transform the building process, “designers” are adopting

new roles, expanding their focus to include digital fabrication of curtain walls and custom

building elements, and even directing the work of the subcontractors. Some firm are even

offering a Design-Build-Operate-Manage approach that completely removes the

design/construction boundary and extends their influence and control into building operations.

Their expanded focus on the total building lifecycle includes designing, fabricating, installing

and then operating systems for entire building portfolios.

“Abstracted from Autodesk BIM Curriculum 2012: Unit-7”

Given this change in strategies, early involvement of the builders in the design process will

mean higher chances of constructability and potentially lowering cost as decision making can

be carried out earlier; one can expect saving in time and material, and higher predictability to

project execution.



3 Preparation for BIM Modeling

At the Preliminaries Stage

Most projects have a “Preliminaries” stage, whereby you will form the project team and initiate

mobilization activities; for instance manpower and resources requirements (such as

organization chart, Outsource resources, Equipment and infrastructure). Goals and Targets

are also established in the team including Deliverables schedules, Budgets and Scope of

works. Project Management Methodology will now play a vital role in ensuring successful

completion of project. During this stage, BIM will have a significant role to support successful

implementation. We will briefly discuss three aspects that one should review when you

commence with BIM implementation.

a. Standards and Methodology

- Similar to the old days of implementing CAD-Standards, BIM implementation is

similarly dependable on this. Having an establish standards such as file-naming and

project directory organization is important to start off your project without delays The

method of modeling with your BIM tools must be in place to guide your modeling team

else the information compile in the project model may return inconsistent result. For

most organization, a basic start-off in the BIM tools would be a template.

b. BIM Applications

- The biggest difference in BIM applications’ results between Design Phase and

Construction Phase relies on the Goals and Objective. Both phases may use the same

BIM applications but the expectations on the results serve different needs. For

instance, using BIM-4D in the Design Phase may be used to determine viability of a

Construction Approach to the Site Constraint, but the Construction Phase will need to

know the actual sequence of the parts construction.

c. File Exchange protocol

- We cannot eliminate the possibility of working across different BIM tools. For that, you

need to be aware of how BIM information can be transport across these platforms.

Adopting an Open-Standard may be the next best option but you must also be aware

of information loss possible out of such transformation.



BIM Model Views Representation

Before we go further, it is important to understanding some concepts in BIM-Model.

Traditionally, CAD software manages information by individual drawings which may or may

not be link to one another. For that, it was difficult to ensure consistent among the information

presented in these CAD files. The focus of work with BIM-Modeling is Model-centric. Meaning

the operator focuses in ensuring the 3D model is created as accurately as possible with its

respective information, and any drawings (such as Plan, Section or Isometric) are

automatically generated. This way any of the changes made to the drawings or model, it will

automatically ensure consistency among related drawings. For this, most BIM tools termed

these “drawings” as “Views”.



Level-of-Development / Details (LOD)

In “AIA Document E202-2008”, LOD is define as follows

Level of Development. The Level(s) of Development (LOD) describes the level of

completeness to which a Model Element is developed.

As project progresses over different phases in a project, the level of information also

progresses. Naturally as a particular set of information in the Model moves from Design Phase

into Construction Phase, we would expect it to contain more elaborate content, for instance

the materials on a wall. Contractors implementing BIM into their project must be aware of

extended information that needs to be incorporated into the Model and some BIM applications

may not be effective without the relevant data. The diagram here shows how the information in

an element, prepared in the Design Phase can progressed into Construction Phase, and

subsequently into the Fabrication Phase.



4 Typical Information Relationship

An ideal BIM environment has a centralized repository where all relevant parties in a project

communicates and collaborates. Unfortunately, constraints in our current situation limit this

ideal setup, such as Technology, Culture and Cost. Therefore, you need to manage your work

process around such limitations. You must also be prepared to manage overheads in your

processes to achieve the desirable results against your objectives with BIM. Remember our

primary objective at this point is to achieve coordinated construction drawings.

The diagram schematically presented the types of information you can expect from

construction environment.

- Architectural drawings

These drawings contain the architectural intent of the design works. In most cases, you

may not see a very clear distinction between architectural objects and structural objects.

And many times, we would assume this association of discipline. Therefore one must be

prepared to make changes along the process of modeling this information. The types of

information you need to be aware of are the intent of the architectural design which usually

represents the theme of the design. As contractors, we will need to evaluate possibilities of

achieving the construction for the design. And where constraints and limitations arise,

counter proposal must be endorsed by the designer (consultants) before the actual works.

Architects

Structural Engineer Building

Services Engineer

Landscape Architect Quantities

Surveyors

Others

BIM Model

HVAC

Elect

Piping

Sanitary



- Structural drawings

These drawings contain the structural definition of the project; conceptually it is the

“skeleton” of project. They do not contain architectural objects such as Railings, Doors and

Windows but may on circumstances; these may be presented to demonstrate a design

purpose. Typically, they contain only elements such as Columns, Beams, Slabs and Load-

bearing walls. You can expect to see different in dimensions between Architectural

drawings and Structural drawings. This is because finishes information are usually not

represented in Structural drawings. Do note the information here are always associated to

a set of “analytical framework” which is used for structural analysis and design. But for

contractors, this information more often than not, do not serve much purpose. We would

ignore this rather managing it. One of the most challenging information to manage here is

the differences between Architectural design and the Structural Element.

- Building Services drawings

These drawings are usually based on Architectural drawings during sub-contractors award

stage. One biggest challenge here is to visualizing and understanding the design in 2D

line-work diagrams. These 2D line-work diagrams are mostly schematic and do not always

represent the final layout of the design. This could be due to on-ground discovery of

structural elements, or more than one sub-trade contractors are involved in the project. For

instance, the award of sub-contractor for sanitary works may not be same sub-contractor

for piping. As such, depending on whose works are done first, more often than not, the

subsequent sub-contractors will change his layout in-situ on site. Thus these are some

discrepancies between the design layouts against the constructed layout you must be

aware. The sort of information you need to manage would be the knowledge of structural

elements so that design do not make changes on site. Similarly, the existence of other

sub-trade information allows for early planning, design and costing for the project.

- Landscape drawings

This is becoming more a demand these days as a separate item in the system. Landscape

on a smaller scale tends to be managed by the Architects. With the growing demand for a

“garden city”, landscape works are now becoming more a major trade to the construction

project. Landscape information mostly take baseline from Architectural drawings but the

knowledge structural elements is important especially if you have earth-fill in which can be

quite significant to the loading. Most landscape designers would be concern with issues

such as water proofing layers and pest control mechanism. For this you need to be aware

of these requirements has they have bigger impact over longer term to the project and

downstream operations.



- Quantities Surveyors

The overall management of project estimates and costing accountability to the project

owner usually lies with the Quantity Surveyors. Progress claim for work done are normally

checked here and any variations estimates are managed by this team. But these do not

imply contractors do not carry out their own estimation. Contractors needs to be able to

manage estimates differences between own and those from the quantities surveyors.

Using BIM to manage this can eliminate lots of discrepancies if the approval BIM model is

used between both parties.

- Others

These can includes Land Surveyors, Lighting Designers and Interior Designers depending

on the scale, complexity and nature of the construction project.



5 Project Information Modeling – Part 1

The current situation in our local Construction Phase is still delivered very much with 2D

drawings. Our Consultants by and large, has not reached a platform to release a BIM-Model

for Contractors to work on their deliverables. As such, many Builders are taking into their own

effort and resources to develop “early BIM-Models” so that they arrive at a “Construction

Model” where all their deliverables are dependable upon. This cycle has unwittingly created

significant overheads into Construction companies. The following suggest how you can

prepare the “early BIM-Models” so that a “Construction-Model” can subsequently be prepared.

Control Information

Typically the Architectural drawings remain the foundation to all information in a project. As

such, “control-information” are retrieved from Architectural drawings and reproduced into the

BIM-Model. The most basic Control-information is Project Elevations, Project Grids and

Project Boundaries. Control-information can include other parameters such as Setbacks and

Datum. Control-Information must not be copied from the source file to ensure they are correct

and accurate for downstream purposes. Given the nature of most 2D CAD files today, the

integrity of the content presented can sometime be wrong. For that to ensure accuracy and

consistency in the model, it is should be a practise to avoid copying. You will have to read the

information presented in the source drawing files and re-create them in your project modelling.

Once you have completed this, the source file can be compared with what you have modelled

and any discrepancies can be raised as RFI. Whatever you are modelling at this time is still

considered LOD-200. If the “Control-Information” has no discrepancies, they can now be used

for subsequent discipline modelling (such as Structural and MEP). Here, you will no longer

need to reproduce the information manually but use it as reference (or copy).

Project Modelling at LOD-200

We will typically model the Architectural information first. The sequence of modelling with your

BIM software has implication to downstream results. For instance the different methods of

modelling your floor slab can result in different volume information. You are thus advised to

experiment with your own BIM software to better understand the required information out of

the model.

At this stage, our modelling activities are still considered LOD-200. The reason behind this is

because we are not receiving BIM-Models from consultants. Mainstream information coming

from Consultants today is still 2D drawings. Using this source of information, builders will have

first re-create these BIM-Models and coordinate the information among different engineering

discipline before they are consolidated into a Construction-Model. And any subsequent



information development will be done on the Construction-Model. Here’s an illustration on how

the process comes together.

We will discuss a little more on the process in the “Consultant Model” development. Once the

Architectural BIM model has been developed, we will then develop the Structural BIM model

using the Architectural BIM model as reference. There are two approaches to managing this

task, you either visually inspect for discrepancies or you can perform a CLASH DETECTION

application to compile a report to work on. Only when the BIM model between the

Architectural and Structural discipline has been normalised, you will then commence with the

MEP BIM model. More details on this process will be presented in later lectures.

In the upcoming LAB exercises, you will be using Autodesk Revit to perform the process

illustrate above. The suggested process diagram here is applicable for new adopters of BIM in

the Builders environment.

Documents

BIM_BM3806(3)_Edumnd Leong_22062012