details in bim a process conceptualization

Concepts of Detailing BIM

Projects

1

Detailing BIM

Telling the BIM design story more effectively The combined use of 2D+3D views for Detailing enhances the communication of Design Intent and allows more efficient Coordination & will contribute to an overall better, more efficient Documention & Construction process.

The 2D+3D concepts herein are not only apropos for Details, they are also suitable for most other types of views, such as in creating 2D+3D Plans, Sections & Elevations.

There are several ways to detail for BIM projects & we will focus on the use of Revit, though these concepts are software indifferent. Each method or topology of detailing is best used to reach specific documentation, coordination & construction needs.

Detail Topologies

Details can be intellectualized as having two main Typologies, namely 2D & 3D: combining corresponding 2D and 3D views on a sheet create the desired 2D+3D BIM solution.

There are three main types of Two‐Dimensional (2D) details.

There are two main types of Three‐Dimensional (3D) details.

2D Detail Types DT Drafting View Details DS Detail Sections DH Hybrid Details 3D Detail Types 3M 3D Model Views 3T 3D Details

The two‐letter prefixes above are View Name prefix‐codes, used to differentiate View Types for easy identification in the Revit Project Browser.

Detail Methodology: The Plan

The first key steps for any successful endeavors are planning: and detailing a project is no exception. The quantity & types, status, etc. of details are to be planned for beginning in the early to mid SD phase with more refinement when approaching the transitions to the DD & CD phases, as well as throughout those phases. This management style, used on all views (not only details) will allow a tight integration of the Model with the Documentation Set and the overall Project Delivery Schedule.


Projects

2

Partial “View List” showing the organization of Details using the “View Heading 1 & 2” parameter values, note the all important

Detail Responsibility, Status & Due Date fields.

Planning & managing views in Revit is best accomplished using a “View List” schedule, with custom parameter values. These parameters are used to manage the strategy & help ensure that what has been planned for is being addressed, by whom & what the status is, at all times.

All parameter values MUST BE kept up with or the entire plan & project will break down.

Planning details & other Views could be done by exporting schedules to other database software but that is not recommended for many reasons, including the fact that data outside of the BIM Project file requires re‐working, updating & leads to inconsistencies, errors and omissions.

Detail Use Cases

As discussed detail methodogies can be broken out for several use cases, including: Typical Details, Project Specific Details, Hybrid Details, 3D Views & 3D Details. 3D views & 3D Details will be used in conjunction with the more historically commonplace 2D details, to powerfully augment the AEC process for BIM projects, providing all parties a greater understanding, better coordination & easier visualization & execution of their scope of work.

3D Detail View with corresponding Partition Type (2D) Detail & Partition Schedule


Projects

3

2D Detail Views

“Drafting Views” are used for typical, non model specific details.

Drafting Views These are only used for details where the model itself is not necessary for the detail to exist & be correct, such as Typical Details.

o Typical Details, include standard details such as waterproofing details, where the actual size of the model objects do not affect the detail’s prescriptive directions. Detail Components from within Drafting Views can be copied into Hybrid

Details lending efficiency to the creation or transition from a “Typical” to “Project Specific” detail.

Detail Section Views (Section Details) are used for project specific details & hybrid details. Derived from the live model, these are used for Project Specific Details, as well as Hybrid Details.

o Project Specific Details show a combination of the live view of the live model with 2D Detail Components added over top.

o Hybrid Details are created the same way as a Project Specific Detail, except that each component in the live model view has a 2D Detail Component laid on top of it, then all model categories are turned off (except of course for Detail Components). The uses for these hybrids would be to allow components to be moved out of

the way, to show items such as waterproofing & vapor barriers that traditionally have zero‐thicknesses in the actual model’s assemblies.

These details are technically not to scale (NTS); therefore dimensions should only be used in limited cases and never for the overall size of an assembly.

3D Views & 3D Details

“3D Views” are used for typical 3D visualization & coordination purposes, as well as 3D details.

3D Views

Used ‘as is’ for traditional needs & to augment the detail package o 3D views, in regards to detailing are

best used as accompanyments to corresponding 2D details, to add visualization clarity and coordination enhancements, per image page 1.

3D Details Using a saved 3D View & adding appropriate annotations. See image right & Appendix A.

o It is not suggested to annotate every aspect of a 3D view for detailing purposes, so be judicious & use them as “augmentations” to the more thorough 2D Detail.

3D Detail 3D View


Projects

4

Timing

Now to pull the plan & BIM project all together we must discuss time. One of the important aspects to each project is timing. Planning the correct amount of time for tasks through the overall project is something that must always be given complete adherence to. With the knowledge of “what is to be done, when it will be done & by whom will it be done”, project management is made more effective, providing the BIM team with an environment to do the best possible job: that is the result of good planning & proper scheduling & timing. When setting production schedules, production time for detailing, like creating any view or any sheet’s worth of views, can begin to be thought of in simple mathematical terms.

If a person can create 5 Details a day (This is perhaps an aggressive #, mind you) and there are 100 details identified as ‘needed’ then it will take 20 working days: but that is strictly for producing them... Remember revisions, etc.

o That means PENCILS DOWN is required for the ‘design’ of details (at worst) no less than 25 days prior to submission but a better timeframe may be 30 working days, depending on the team, as there needs to be QA/QC & time for markups & revisions, etc.

Keeping all necessary details consistent with the BIM model is vital; therefore the timing of the detailing’s design process must follow guidelines similar to the ones below.

Tasks, Projects & Production

When Project or “Task based” schedules are created they must be inferred to include every possible factor, beyond simply the individual task itself. These factors include the Project or Task’s deadline, Design time*, QA/QC, Production & Transmission. The subsequent list is an abstracted analysis of what to schedule for & the potential factors involved. Project = (Design + QA/QC) + (Production+ QA/QC) + (Submission + Contingency) Design = (Phase specific Completion Date – Pencils Down) Production = Modeling + QA/QC + Documentation + QA/QC *Pencils Down = Completion Date – (Design QA/QC + Final Production + Final QA/QC + Submission) QA/QC = (Review + Markup) + (Revision + Re‐Review…) Contingencies = Estimated % of Project time for unforseen delays, etc. (judgement call) Submission = Check Print + (Final QA/QC + Final QA/QC Revisions) + Printing + Transmittal

If Design, Detail or Production teams are allowed to meander and not hold to tight & rigerous schedules (or if there is an unrealistic schedule), then the project can expect to run into disasterous results, errors, ommissions and budget overruns.

BIM or no BIM.


Projects

5

Pencils Down

Pencils‐down should be considered one‐of (if not “the”) most honoured factors in a project. If a project is to be delivered as

coordinated & complete, then allowing production, revision & verification time after the design is finished is vital (read as: VITAL). One large & impactful stumbling block to budget is when the project is not properly executed within the schedule.

A recurring impediment to completed, coordinated & on‐budget projects in AEC is when one part of a team does not leave enough time for necessary, future work: such as if a Design team is not completed by the end of DD. Remember: that is what DD is for… Design Development. There are always items that need to change after they are planned for and although this may need to

happen once‐in‐a‐while, if unplanned changes are too numerous & is the status‐quo then success can only be tenuous at best; and definitely not the desired way to run a business. Another example of negative impacts to a project is in the design of Details. This is equally important a part of a project that needs to have a pencils‐down date (or dates). Details are to be ‘designed’ progressively throughout a project; but each phase’s details need a schedule that allows for both creation & production (including all the QA/QC & revisions, etc.). The first‐pass details are best designed early on in a project; beginning about 30‐50% SD and progressively developed through DD and optimally having a detail‐design, final Pencils‐Down before 75% CD. The third example of negative impacts to schedules is “The Meandering Production Team”. If a team is allowed to work without a concise plan of attack, derived from the comprehensive project schedule & broken out into more & more granular, ‘task‐to‐date’ sub‐plans; then the project can expect similarly undesired results.

The ‘Efficiency’ Bottom Line

Create an environment of efficiency to deliver success.

Create good plans & manage them closely for all aspects of the process: Design, Detail & Production; Coordination, & Submission...

Execute the plans & make people accountable & empowered. Do exactly what is planned, no more & no less (unless the plan is changed).

Keep teams on point by eliminating unnecessary meandering & overworking; ensure that the team holds to tight, rigerous & agreed upon managed timelines.

Every submission of a project has known items to be included and with the appropriate planning accurate performance & success can be managed.


Projects

6

Concluding Thoughts

This paper focuses on Detailing BIM projects being broken out into several overarching themes that all work toward the bottom line: Efficiency. The philosophy of ‘planning the work & working the plan’ suggests that as being a fundemental principle to follow for overall project success. Being built on good planning, teamwork and management, communication & follow‐through a BIM project should realize successes for the entire AECO team. The main ideas discussed have been:

Detail Typologies

Detail Methodologies: The Plan

Detail Use Cases o 2D Details o 3D details o 2D+3D Combined

Timing

Task, Project & Production Planning

Pencils Down

The ‘Efficiency’ Bottom Line

Creating and following a rigerous plan will allow each component of the BIM project team to create their best possible work & ultimately better projects toward a more sustainable business model.


Projects

7

Appendix A

3D Annotations in Revit There are powerful uses for annotating 3D views of a BIM model. When used in conjunction with 2 Dimensional Details, the 3D views & 3D details provide greater project coordination & communication. Revit has very good tools to annotate 3D views and they are found on the Annotate Tab of the ribbon.

The active annotation tools in Revit 2012’s 3D views: Dimension Panel Aligned, Angular, Radial & Arc Length

o All dimensions must be placed on a “Reference Plane” (RP), so it’s suggested to place the “Set Workplane” tool on the quick access toolbar (QAT), since the RP will want to be

changed efficiently. Spot Elevation Spot Coordinate Spot Slope

Detail Panel Create Group

Text Panel Text Spelling Find/Replace

Tag* Panel Tag All Tag by Category Multi‐Category Keynote (Element, Material & User)

3D views must be locked to use Tags or Keynotes

Use the Help System & search for “Adding Tags and Keynotes in

a 3D View” to find more on locking & annotating 3D Views.

details in bim a process conceptualization

Documents