Measuring the Impact of BIM in Design-Bid-Build

Transcription

1 Measuring the Impact of BIM in Design-Bid-Build A Case Study Dace A. Campbell, AIA, LEED AP // BNBuilders // 2 November 2011

2 The Associated General Contractors of America (AGC) is a Registered Provider with The American Institute of Architects Continuing Education Systems. Credit earned on completion of this program will be reported to CES Records for AIA members. Certificates of Completion are available on request. This program is registered with the AIA/CES for continuing professional education. As such it does not include content that may be deemed or construed to be an approval or endorsement by the AIA of any material of construction or any method or manner of handling, using, distributing, or dealing in any material or product. Questions related to specific materials, methods, and services will be addressed at the conclusion of this presentation.

3 Founded in 2000 Headquartered in Seattle San Francisco, San Diego, Portland, Montana $300+ million in annual volume 250+ employees $10K-$70M projects National Recognition ENR Top 400 Contractor 2009, 2008, AGC of America Construction Safety Excellence Award Winner of AGC s Grand Award for Safety Excellence for Mid-Size Companies 2008 ENR Best of the Best Award for Project Management 2008 AIA BIM Award Significant work in collaborative, integrated delivery Integrated Project Delivery Design-Build GC/CM Negotiated work Key markets Life Science and Research Healthcare / Medical Facilities Public / Civic Spaces Offices and Corporate Headquarters Education (K-12 and Higher Education) Mixed-Use Facilities Hospitality Commercial / Retail BIM In use since 2006 Applied to $500M and 2M s.f. in new construction Focus on PE s and Supts as BIM users Recognized as national and local leader

4 A Word About BIM BIM as simulation Unlike manufacturing, there is only one chance to get it right in construction Mockups are expensive and time-consuming BIM is a virtual prototype Build it virtually to perfect the product and process Simulate the building to: Increase Confidence Understanding Communication Reduce Delivery time Project cost Waste Injuries Conflicts & RFIs

5 Why BIM? Don t do rework. Do prework.

6 Position BIM for 3-D MEP coordination Widely accepted as the low-hanging fruit entry into BIM Clash detection is no longer enough Before exploring ROI of other applications of BIM, have we truly measured its impact on 3D coordination? Some valuable studies into the impact of 3D coordination across the industry, generally and anecdotally There are few studies which objectively measure its true impact on a specific project Every facility is unique Program, site, project team, etc. BIM goes hand-in-hand with collaboration and integrated delivery BIM is rarely applied to hard-bid projects where collaboration is often de-emphasized in favor of other factors.

7 BIM in Design-Bid-Build Case Study Project This case-study presentation will discuss and analyze the impact of BIM as applied in design-bid-build of a rural, public, higher education facility Spokane Falls CC Science Building Spokane, WA Construction: $16.5M 75,000 s.f. Science lab building at rural community college

8 BIM Considerations BNB had no prior experience applying BIM to a public, low-bid project Forward-thinking architect 3D coordination required in the spec But only required for specific lab rooms with intense MEP systems Handed over the Revit source model Hard bid delivery method doesn t encourage collaboration Subcontractors largely inexperienced, disinterested in BIM Little incentive to go beyond requirements in the spec Desire by BNB to do more than the minimum with BIM But stronger desire to NOT lose money on the project!

9 BIM Uses 0 Design Visualization 1. Surveying 2. Design Assistance & Constructability Review 3. Site Planning & Site Utilization 4. 4D Scheduling and Sequencing 5. 5D Model-Based Estimating 6. Subcontractor/Supplier Communications 7. Systems Coordination 8. Fabrication and Installation 9. Prefabrication 10.Operations and Maintenance

10 BIM Uses 0 Design Visualization 1. Surveying 2. Design Assistance & Constructability Review 3. Site Planning & Site Utilization 4. 4D Scheduling and Sequencing 5. 5D Model-Based Estimating 6. Subcontractor/Supplier Communications 7. Systems Coordination 8. Fabrication and Installation 9. Prefabrication 10.Operations and Maintenance

11 Design Visualization Mech Elec FF&E Arch Struc Lscape

12 Scope of 3D Coordination 8.7% of total floor area required by spec Including Roof, we coordinated 37% of total area ~75% of the total MEP systems ~Density of MEP in these areas was 5 times that of the rest of the building Plus (2) rooms on first floor

13 Systems Coordination Good coordination requires: Strong start -- Kickoff meeting to establish expectations and protocols Strong documents Scope checklists Model standards Schedules Designer participation clarify/defend design intent

14 More Kickoff/Coordination Documents

15 Annotated Superplot to Track Conflicts

16 Underground Systems Coordination Challenges: sub participation maintaining the schedule existing conditions under slab P v. S waste pipe through top of interior footing P v. E waste pipe through electrical conduit

17 Coordinating A/V Equipment

18 Coordination on Roof BEFORE AFTER

19 MEP Coordination Results: Conflicts Trades: HVAC, mechanical piping, electrical, plumbing, fire protection, AV FIRST PASS CLASH DETECTION FINAL SIGN-OFF UG L1 < L2 100 s RF 100 s Conflict Resolution: ~10,000 clashes discovered with NavisWorks ~1000 significant conflicts identified and resolved 76 outstanding conflicts left at time of sign-off (resolved in the field)

20 MEP Coordination Results: RFI s Method Percent of total building area Percent of MEP systems Density of MEP systems Field-generated MEP-related RFI s MEP Coordination Method Comparison 2-D superplot /informal 3-D Clash Detection 63% 37% ~25% ~75% 1 : Percent of RFI s 71% 29% % RFI s / % of MEP : 1 % RFI s / Density MEP : 1

21 MEP Coordination Results: Change Orders Scope Entire Building Change Orders Non-MEP Systems MEP Systems Original Bid $13.6M $7.94M $5.66M Change Orders ~$3M ~2.99M* ~$10K Percent CO s 22% 38% 0.17% CO Ratio (Entire Bldg vs. MEP) CO Ratio (Non-MEP vs. MEP) * Approximately 50% due to owner upgrades, 33% due to unforeseen underground conditions, 17% due to errors in design documentation

22 Subcontractor Communications

23 Deck Coordination: PT vs. Penetrations

24 Deck Coordination: PT vs. Penetrations

25 Coordination: Slab Edge vs. Embeds

26 Constructability Review

27 Layout Drawings for Slab Depressions Started with finish floor plan view from architect s model (terrazzo in concrete slab) Several iterations and markups by field staff based on construction conditions P.E. dimensioned and noted slab depressions for terrazzo in PT deck Result: clearly legible, field-specific view of the model for accurate formwork layout

28 Prefabrication Exposed stainless steel ducts through joists Clean seams and high level of finish required shop prefabrication Joists not in A/E model

29 Joist Modeling: Custom Revit Families Standard RVT 24 LH-series joist BNB-modeled 24 LH-series joist

30 Prefab: More Coordination Required! Prefabricated duct in the shop Flawless installation of prefab d stainless ducts

31 Conclusions Only some portions of the project were coordinated with BIM Due to the unique circumstances of this project related to the specifications and subcontractors capabilities We have been able to: Study the dramatic impact of BIM-based coordination of building systems on the project Objectively compare its effect on RFI s and change orders to areas of the building that were not coordinated with BIM Demonstrated enough value of BIM for coordination to earn the trust of the team to pursue other avenues and uses of BIM for continued benefit of the project

32 What s Next All BIM, all the time LEGAL Model-sharing more prevalent in AEC CULTURAL Old school designers and builders changing habits, changing careers REGULATORY Agency review PHYSICAL Paperless construction at project sites trending towards Augmented Reality OPERATIONAL 6D use of BIM to support facilities operations and maintenance

33 Questions?

34 Thank you