There can be little doubt, in 2018, that the principles underpinning BIM (Building Information Modelling) have become the established starting point for all construction projects across the UK.
The UK government has also played an important part in kick-starting the popularity of BIM through its Digital Built Britain initiative and Level 2 Mandate.
Implicit in this uptake of BIM is the key role played by BIM-ready surveys. They provide the base data and reference points for all subsequent activities on building projects of all types and sizes.
Enabling building professionals to ‘sing from the same hymn-sheet’ is probably the single most significant step the highly conservative construction industry has ever taken.
For architects and other building professionals to derive maximum competitive advantage from BIM, they should make BIM-ready surveys their first port of call when sourcing and co-ordinating resources for every project.
What Is A BIM-ready Survey?
An equally important question is why are BIM-ready surveys so critical to the success of building and development schemes?
It’s clearly vital to set out the parameters of how physical built assets will be created. Important too is understanding the essential chain reaction and collaboration between the various design and building disciplines. And how it all puts meat on the bones of an as yet unrealised conceptual vision.
BIM surveys deal in the art of the possible. They add 21st century accuracy through the application of innovative technologies. This is part of an exciting strategic exercise that turns ideas into reality by feeding crucial data into the BIM process.
In practical terms, a BIM-ready survey is the first stage in the ‘cradle to grave’ lifespan of a refurbishment or redevelopment project. Simply put, its purpose is to provide architects and designers with the crucial data they need to develop a credible and creative design solution.
Revit and other BIM software enables users to interpret highly accurate and reliable data captured from a digital site survey using a terrestrial 3D scanner (in conjunction with conventional survey techniques).
Laser scan surveys deliver hitherto unmatched speed, accuracy and awesome levels of detail – as well as all the benefits provided by Point Cloud data (covered later in this article).
The key deliverables of a BIM survey include:
- Providing a Point Cloud data file almost immediately to the desktops of everyone involved with the project – architects, interior designers, project managers and structural engineers. BIM-ready data gives the design teams a powerful, quick-to-use visual and measurement resource, without the need for repeated visits to the site.
- Providing a 3D Parametric Model of an existing building, constructed using the point cloud data to create an ‘intelligent’ model which can be used as a base model for the design. In compliance with PAS 1192, the model will be constructed to the agreed ‘Level of Development’ (LOD).
- Other information can include 2D plans, sections and elevations delivered with the design team’s Revit template.
Key Takeaways of A BIM-ready Survey
- Working closely with professional surveyors is an essential part of developing the project specification at the outset. This helps to define what information is needed. It applies to the Level of Detail (LOD) relating to the graphical representation of the building; and the Level of Development (LOD) as it relates to both the graphical representation of the building and the properties of objects within the building.
- Fast delivery of the Point Cloud data files to the architect’s desk-top means they can start the design process at the earliest opportunity.
- The data files provide a permanent historical record of the building. This is particularly valuable if it is ‘listed’.
- The laser scan survey can be used as a reliable source of accurate data at all stages of a building’s life.
By providing a visual and dimensionally-accurate record of ‘as existing’ conditions in 3D HD, team members can access, navigate and carry out basic interrogation remotely. Armed with accurate site data, designers of architectural and interior design projects can work with reduced overall commercial risk, and with greater confidence and certainty.
The True Benefits of BIM Surveys
These fall into three core areas – Laser Scanning, Point Cloud Data and Digital Construction – the main features of which can be summarised as follows:
The value of Laser Scanning
- It provides a more comprehensive data set than traditional surveys
- It is quicker and captures more data than traditional surveys
- The quality of the site data is pre-qualified and is therefore less likely to involve human error and making inaccurate assumptions
- It allows for the preparation of a more precise canonical (authoritative) 3D model
The value of Point Cloud Data
- It allows for a more meticulous, ratified modelling process
- It provides the design team with a visual and measurable reference source of the site. This also removes (or reduces) the need for – and cost of – returning to the site
- It provides a historic record of a site
- It meets the needs of clients who may prefer to take delivery of the Point Cloud data and construct the model themselves
The value of Digital Construction
- 3D modelling provides a more complete picture
- Digital information is quick and easy to distribute, share and access on a regular basis
- Working digitally allows for more efficient collaborative working practices and the implementation of rigorous processes
- It is trustworthy data that provides the assurance of working with reduced commercial risk
Collaboration is the key to enhancing efficiency and productivity
BIM methodology is all about collaboration and the benefits that derive from design team members sharing identical data. This leads to easier collaboration and more harmonious working as well as enhancing output efficiency and productivity.
Effective collaboration and improved information management reduces the risks of misunderstandings between team members. Data-rich 3D digital surveys – containing a high degree of dimensional accuracy – give designers the confidence that their designs are based on accurate information.
Project instigation and progression is greatly facilitated, whilst the scope for more effective problem-solving is further enhanced through closer working relationships between team members and clients.
This occurs when everyone is involved in defining what information is required, deciding on what format should be used, and how the data should be handled in order to avoid shocks and costly mistakes later in the process.
Clarity of Specification is part of the value added appeal of using a BIM-ready survey
Other, more strategic, factors play a key role in the value-added appeal of using BIM-ready surveys. Achieving ‘clarity of specification’, for instance, ensures that a project has clear deliverables, dimensional accuracy and appropriate levels of detail.
This is a key strength of CA Design Services, the UK data survey consultants, who are enthusiastic standard bearers for BIM-enabled working. National Accounts Manager, Mark Johnson, explains their collaborative approach:
“When it comes to developing the specification of the 3D model,” says Mark, “we always make sure there’s close collaboration between the design team and an experienced BIM survey specialist who can provide appropriate technical advice on the best method for capturing the required site data.
“Of course, the digital survey in Point Cloud file format generally captures more site data than is needed, but this provides the design team with a rich source of visual and measured site data to help with their understanding of ‘as existing’ site conditions. In many cases, it can also rule out the need for costly surveys in the future.”
A good example of how CA Design Services turn their laser scanning and modelling expertise into tangible results can be seen at the Riverside Ice and Leisure Centre redevelopment in Chelmsford, Essex.
CA Design Services were brought in by Pick Everard at the outset to advise on developing a design strategy. The process was initiated with a 3D HD laser scan of the proposed ice rink and leisure centre. This provided the architects with accurate and reliable information that could be used by all parties throughout the project.
The survey data was registered as a Point Cloud file from which a 3D Revit model was created in just three weeks. This enabled the design team to start work right away – and with total confidence in the integrity of their data.
Job-specific digital surveys of this type meet the wider information requirements of the entire design team. Capturing the maximum amount of information required in a single site visit ensures the client receives best value from the survey.
Similarly, the adoption of Building Intelligence Modelling allows for the implementation of a comprehensive execution plan. This will show how information is co-ordinated within the team and how interaction will be best achieved.
Finally, the benefits of BIM-ready surveys can be sold to clients in an easy-to-understand format that demonstrates how a better-quality end-product can be delivered on time and on budget.