How is survey data used by architects within the RIBA’s Digital Plan of Works?

Stage 0 - Strategic Direction

This stage is to ratify that the project is the best means of achieving the client requirements. It is not about the design or practical details but focuses on making the right strategic decisions and capturing these in a Business Case which includes evaluating the pros and cons, the risks and the budget.

The following site surveys may be required, or alternatively it could be worth investing in existing geospatial information. There are multiple sources of data available on the market, that could provide a good starting point for your project.

Topographic surveys

A topographic survey records the site terrain, boundaries, levels and features critical for understanding the potential of a site for further development.

Other valuable resources include Ordinance Survey, HM Land Registry records, or open-source GIS datasets.

Utilities / underground surveys

This type of survey is used to check the site for any below ground wiring, water pipes, power, fibre optics, drainage, sewage, gas or telecommunications that may restrict development.

Other things to consider include supply companies who hold service records which can be requested. This can take time but once obtained, they can contain valuable information. It is also worth considering previous site usage.

Site visits

To consider whether the site looks different to the available records. If so, additional surveys may be required.

Condition surveys

To consider the physical condition of the structure and fabric to inform decision making on whether to demolish or refurbish.

Other considerations include asbestos surveys which may be required.

Stage 1 - Preparation & Briefing

All data captured at this stage informs the development of the project brief seeking to set the scope and scale of the project and any critical site constraints.

The existing geospatial information obtained at Stage 0 is usually very general  therefore, once planning starts, more detailed resources should be generated to serve as base for the design.

Consider appointing a survey firm at this point, to establish, maintain and update a survey control network throughout the lifespan of the project, as this will help prevent coordination issues derived from different surveys relating to different coordinate systems, which usually lead to expensive design clashes.

Topographic surveys

Used to record the site terrain, boundaries, levels and features critical for understanding the potential of a site for further development. Historic site information may be required.

Other considerations include the scale range of the data:

While OS tile scales range between 1:1250 and 1:2500, Topographic surveys can be delivered at larger scales (1:100; 1:200; 1:500, etc) which are more appropriate scales for the design of a project as they contain smaller detail that will be omitted on the OS tiles.

GPR surveys

A non-intrusive survey to identify any hidden services using Ground Penetrating Radar. This ensures that all critical non-metallic underground services are identified, that can’t be traced by other means.

MEP ‘as installed’ surveys

Detailing the mechanical, electrical and plumping on a site to plan for the installation of additional services that will be required to fit into the existing network.

Other considerations : Laser scanning is usually optimal for MEP as-installed surveys but bear in mind that scanners can’t penetrate walls, so the services need to be exposed ahead of the survey.

Verification surveys

These confirm validity and accuracy of any existing information.

In cases where comprehensive plans are available, a simple site inspection

Measured building surveys

Used to record the fabric and architectural design of a building.

Consider seeking advice on the most suitable instrumentation for the project: a laser scan survey is usually more accurate and comprehensive than traditional methods but, depending on the scope of the survey, the extra spend might not be justified. Photogrammetric and Matterport surveys could also be good alternatives in some cases.

Fire safety plans

Basic floor plans may be needed to develop a fire safety plan.

A Matterport survey may be a more cost-effective option to consider, as an alternative to traditional measured building surveys.

Stage 2 - Concept Design

The architectural concept is prepared incorporating the strategic engineering requirements, aligned to the cost plan, project strategies and outline specification.

Survey data captured in Stage 1 delivered as a 3D model will inform the architect’s concept design, as they start to address the form, scale and general appearance of the building within its location and context.

If you are adopting a BIM strategy for your project, you will be planning to integrate and coordinate data from different sources into one single platform. All aspects of the design should use a common coordinate system to prevent clashes, which can be managed and coordinated by your appointed survey firm.

Additional surveys

The design may require more in-depth surveys to capture specific data requirements that were previously out of scope or to update inconsistent or inaccurate information.

Other considerations may include Larger scale topographic surveys, drone surveys, underground CCTV inspections, laser-scan surveys of plant rooms, etc.

Stage 3 - Spatial Co-ordination

At stage 3, the architectural and engineering information is spatially coordinated. Survey data required at this stage ensures the architect’s Concept Design can become a physical reality. 3D models created at earlier stages are developed into coordinated BIM with more additional data included into the core model enabling clash detection.

Detailed surveys

Detailed surveys of specific areas, structures, or services, because of the clash detection process. These can include intrusive surveys to expose a building structure, or more detailed building services surveys where the feasibility of any proposed design needs to be validated to avoid potential costly redesigns at a later stage.

Stage 4 - Technical Design

All design information required to manufacture and construct the project are completed at this stage. Such as specification details of MEP for future planned maintenance. Surveys are unlikely to be required at this stage.

Stage 5 - Manufacturing & Construction

Surveys commissioned at this stage inform the construction process, ensuring everything is built and installed exactly as designed. This is where most problems occur from poor coordination of survey data in the previous stages. Most of these issues can be prevented with preparation using a common coordination system.

Survey

Site control and setting out surveys are a key part of the construction process and ensure elements of the project are installed in their exact positions according to the design. Other considerations include site engineering surveys and site control maintenance: most of the survey control points get destroyed during this stage so it’s critical to plan ahead for their relocation and the recalculation of coordinates.

Stage 6 - Handover

The building is handed over to the end user, aftercare is initiated, and the building contract is concluded.

Verification surveys

Commissioned to verify accuracy of construction and conclude the Building Contract. Data may also be captured on the as-built and as-installed condition and used for updating the ‘Digital Twin’ models for Facilities Management.

Other elements to consider are as-built topographic surveys and as-built laser-scan surveys.

Stage 7 - Use

Once in use the building will be being operated and maintained efficiently.

Ad-hoc measured surveys

This is good housekeeping with any changes to the structure or layout of the building recorded with a corresponding survey (verification survey, measured building survey, topographic survey, etc). Remember, it’s always more cost effective to keep records up-to-date with limited-scope regular surveys as opposed to commissioning a full survey every few years.

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