There is clear evidence that both design professionals and clients usually do not engage with the quantity surveyor as part of the building information modeling (BIM) process, instead preferring to leave the QS to prepare their cost plans based on the traditional 2D process.
In fairness to the design professionals and the clients, quantity surveyors traditionally have not embraced the whole BIM process. Yet BIM is here to stay, and now is the time for all quantity surveyors to start using BIM as the standard tool for delivering quantity surveying services.
After 10-plus years of BIM software being available, quantity surveyors and quantity surveying firms have been reluctant to embrace this technology for a few reasons:
- Advancement of technology
- Availability of 3D models
- New terminology
- Lifting the perception of the value of the QS
Advancement of technology
In the past 20 years, there have been far more advancements in the tools available to the quantity surveyor to assist them in delivering their services than ever before. For over 100 years, the quantity surveyor has relied on 2D drawings and the ‘faithful’ scale rule to prepare cost plans. However, the skill in preparing an accurate cost plan is understanding the ‘gaps’ in the 2D drawings and specifications provided and also allocating costs to the various risks associated with each stage of the design.
In recent years, the quantity surveyor has gone from preparing cost plans using the ‘paper’ system to initial simple Excel spreadsheets, estimating software inputting quantities from hand measuring of 2D drawings to software that enables measurement of 2D drawings direct from the computer. Each of these advancements were seen as a natural progression in using technology to assist in preparing cost plans. The quantity surveying skill of identifying the ‘gaps’ and ‘risks’ for each cost plan was consistent throughout these advancements.
Approximately 10 years ago, 3D drawings (models) were being made available to quantity surveyors for measurement. This was, and still is, a fundamental challenge for quantity surveyors to accept after a century of measurement from 2D drawings, whether that be from hard or soft copies.
So why has the quantity surveyor been reluctant to accept this next step of advancement in technology?
Reluctance of designers to allow 3D models to be used
As mentioned, 3D models have been made available to quantity surveyors for over a decade. However, when issuing 3D drawings, designers commonly issue this data with disclaimers such as ‘not to be used for measurement of quantities.’
3D models, like 2D drawings are delivered at various stages of the design process. The level of documentation (LOD) for 3D models can be compared to 2D drawings as follows:
- LOD 100 – feasibility/concept stage
- LOD 200 – schematic stage
- LOD 300 – design development and tender
- LOD 400 – contract administration
For whatever reason, designers have been reluctant to issue 3D models that are not substantially complete to quantity surveyors, but will issue drawings in 2D that are at a similar level of completion for measurement.
In Andrew Brady’s presentation at the BILT conference, he advised that for quantity surveyors to utilise this new technology, they need to make the QS profession ‘model-savvy’ and/or ‘data-savvy’ by:
- attending relevant CPD events
- encouraging QSs to meet with design consultants to share how to actually use the model
- communicate regarding how and why design consultants author their digital models the way they do (create feedback/engage)
Quantity surveyors need to become more engaged with the whole BIM process. Involvement from project inception will mean that digital models are prepared in a way that quantity surveyors can maximize the data contained in the models for their various cost plan.
BIM has developed its own language which most Quantity Surveyors are unfamiliar with such as:
- 5D Quantities
- BIM Execution Plans
- BIM Management Plans
- Model Content Plans
- Federated Model
- Object Data
- Modeling Methodology
Quantity surveyors need to understand and become familiar with the implications of each of these terms and how this new terminology can assist them in delivering their traditional services.
Fundamentally, quantity surveyors are still doing what we have traditionally done, but just utlisiling latest technology.
Lifting the perception of the value of the quantity surveyor
Once the quantity surveyor starts to collaborate with the client and design team from the start of the BIM process, the value of the QS may start to be fully appreciated.
During his presentation at BILT, Brady noted that if the QS was fully engaged in the BIM process from the inception of the project. it would:
- Lift the perception of value provided by the QS
- Provide better cost certainty
- Allow for quicker/more frequent cost estimation
- Enable time for better market coverage and accuracy
- Enable better design team direction
- Provide opportunity to leverage for WOL/Life cycle costing
- Encourage QSs to be collaborators, not co-operators
- Create environment where the cost consultants are truly valued