Is this BIM?
As a practice Creu Architecture have been using Revit as a design platform on most of our projects for the last 6 1/2 years. With the anticipated requirement for BIM level 2 on all public buildings from 2016 we thought it would be interesting to assess the compliance of one of our recently completed projects started over 3 years ago against the Level 2 criteria as set out in PAS 1192-2:
‘The fundamental principles of Level 2 information modelling are:
a) Originators produce definition information in models which they control, souring information from other models where required by way of reference, federation or direct information exchange;
b) Provision of a clear definition of the employers information requirements (EIR) and key decision points (to form part of the contract possibly through the adoption of the CIC BIM Protocol) – see Clause 5
c) Evaluation of the proposed approach, capability and capacity of each supplier, and their supply chain, to deliver the required information, prior to contract award
d) A BIM execution plan (BEP shall be developed by the supplier containing:
1) assigned roles, responsibilities and authorities,
2) Standards methods and procedures
3) A resource master information delivery index, aligned with the project programme;
e) Application of the processes and procedures outlined in the documents and standards indicated in table 1
f) Information models to be developed using one of the following combinations of enabling tools:
1) Discipline based software, with individual proprietary databases, that have limited interoperability between them or with associated design analysis software
2) Discipline based software with individual proprietary databases, that are fully interoperable, but with limited interoperability with associated design analysis software
3) Discipline based software, with individual proprietary databases, and associated design analysis software that are fully interoperable
4) Single source platform software with a single external relational database, and associated design analysis software that are fully interoperable’
The project consists of the conversion of a redundant farm building into a domestic dwelling and artist studio for the client in North Wales, procured under a traditional tendering route with a Bill of Quants.
WORK STAGE 2 (C)
The first task was to prepare as existing information:
- The building was manually measured with existing drawings produced in Autocad.
- A site topographical survey was commissioned.
Both these items were imported into Revit for the creation of an existing model of the buildings and the creation of concept designs. Because all design work was being generated in 3d we were able to explore internal option configurations with internal views. In addition we presented the model over a projector in live design meetings with the clients where layout and material options were investigated.
WORK STAGE 3 (D)
The scheme was developed through detail design to a Planning submission as reflected on the images below.
WORK STAGE 4 (E,F,G & H )
On receipt of Planning Approval the same Revit model was used to develop the scheme for construction and tender with the following information derived from the single source:
- 2d plans, sections, elevations and construction details
- Door and window schedules
- Site layout, site levels and drainage, all modelled in 3d with levels derived directly from the model
- NBS clauses embedded into model objects and families for ease of reference
- Material take-offs were used as a checking mechanism for the Quantity Surveyor in the preparation of their BOQ
All information was shared with the design team and client via a common shared online data environment.
See below a video navigating the project Revit model.
WORK STAGE 5 ( J,K )
The same Revit model continued to be used through the construction phase of the project for the following purposes:
- The insertion of the fabricators steelwork model as a .ifc file format derived from tekla for coordination:
- Detailed development for the feature stair design which was contained in the contract documents as a provisional sum. The stair was modelled directly into the Revit model to ensure co-ordination and the generation of the 2d fabrication drawings:
- Interior design and finish options were examined in live design meetings with the clients using panoramas for the:
Main living space
Does this project meet compliance with BIM level 2 in PAS 1192-2? The short answer is no but what are the compliant and non-compliant aspects of this project. The information for the project was produced in models controlled by the originators for the co-ordination of fabricators steelwork, sanitary-ware and services in sufficient detail for the scale of the project. Given the scale of the project, the fact that it was started over 3 years ago and the fact that the implementation of BIM was not a client requirement, there was no Employers Information Requirement ( EIR) document or a need for a BIM protocol. The project followed a structured plan based on the RIBA Plan of Works 2007.
The scale of the project did not warrant an evaluation of the capacity of each supplier and their supply chain, all sub-contractors were taken domestically by the main contractor and the project was not notifiable under the CDM regulations 2007.
- The project was not conceived with the BIM protocols in place and the scale and complexity did not warrant the requirement for a BIM Execution Plan.
- The project was delivered using a co- ordinated project information model from which graphical and non- graphical information was distributed via a common shared online data environment controlled by Creu as the lead designer. All information was shared electronically with the design team, contractor and client using the .pdf file format as well as exporting the Revit model as a .dwf allowing it to be viewed with Autodesk’s free Design Review software package.
- We conclude that this project has adopted some positive aspects of the BIM level 2 protocol. Significant benefits where achieved in the ability to convey the design intent with the clients and in the co-ordination of all the project information. This eliminated any late design changes by the client and any reworking on site which would have resulted in delays and additional cost.
- Agreed BIM methodologies and protocols where not implemented during the project but maybe the type, scale and complexity of the project did not warrant this.
- Moving forward Creu are implementing BIM protocols in line with PAS 1192-2 on projects of sufficient size and complexity which will add structure to collaborative project teams adding to the benefits that the BIM methodologies achieved on this project.