Client Requirements & Project Inputs

Well-defined inputs allow us to:

• Confirm project scope
• Select the correct LOD (2/3/4)
• Establish file format requirements for the project and software compatibility
• Plan the required survey method and scanning duration
• Identify access constraints
• Manage risks and obstructions
• Allocate the correct team, equipment and resources
• Prevent assumptions or misinterpretations
• Guarantee consistent modelling standards
• Deliver accurately and on programme

Insufficient information increases project risk, introduces cost uncertainty, and may lead to rework.

With the right information upfront, we can deliver smoothly and efficiently.

We require a clear understanding of:

• What the model will be used for
• The design or construction stage
• Whether the model supports planning, feasibility, design coordination, heritage assessment, or asset management
• Whether other consultants will be contributing models

This ensures that the LOD, accuracy and modelling approach support the intended purpose.

Typical Project Objectives Include

• Concept or feasibility studies
• Refurbishment or retrofit design
• Coordination with structure/MEP
• Planning submissions
• Heritage documentation
• Phasing and logistics
• Asset and FM integration

Each objective carries different requirements, which we tailor accordingly.

Accurate scoping prevents unnecessary cost and ensures alignment with client expectations.

We need:

• A marked plan showing areas to be surveyed
• Levels or floors included/excluded
• Any external works required (roads, pavements, landscaping)
• Any surrounding buildings that need massing
• Whether roof spaces, voids or plant rooms must be included

This information defines the survey time, access requirements and modelling scope.

As explained on the LOD page, LOD dramatically affects:

• Cost
• Timescale
• Scan density
• Modelling methods
• QA time

We require confirmation of:

• Architectural LOD
• Structural LOD
• MEP LOD (if required)
• Any area-specific LOD variations (e.g. heritage areas at LOD4, general areas at LOD3)

Where clients are unsure, we provide guidance and sample comparisons.

If metadata or scheduling information is required, we need clarity on:

• Room naming conventions
• Space categories
• Uniclass classifications
• Asset information
• Material specifications
• Equipment IDs
• FM requirements

We only include LOI that is specifically requested.

We need to know which formats your team uses:

BIM Formats

• RVT (Revit — please specify which version, as Revit is not backwards compatible)
• IFC (Industry Foundation Classes)
• Navisworks (NWC)
• DWG exports

Point Cloud Formats

• RCS/RCP
• E57
• PTX/PTS

2D Outputs

• DWG
• PDF

Each discipline may require different outputs, so early clarification avoids duplicated effort.

To align the survey with your site data, we need confirmation of:

• OS National Grid usage (Yes/No)
• ODN (vertical datum) requirements
• Local grid systems (if any)
• Shared coordinate needs for Revit
• Project Base Point or Survey Point constraints
• Whether existing models or CAD files have coordinates embedded

Incorrect or missing coordinate inputs can cause significant downstream issues.

Providing existing reference data improves accuracy and reduces time spent clarifying assumptions.

We request:

• Any previous surveys (point clouds, topo, GPS control, measured building surveys)
• Architectural or structural drawings
• As-built information
• Heritage documentation
• MEP schematics (if services are to be modelled)
• CAD or BIM files for context
• Photos or drone imagery (if available)

Even outdated drawings are helpful for planning scanning logistics.

To plan the scan efficiently we need:

• Confirmation of access hours
• Whether the site is live, vacant, occupied or operational
• Security or induction requirements
• PPE or permit requirements
• Any restricted areas
• Any areas that require night-time or weekend scanning
• Whether machinery/equipment will be running
• Any environmental restrictions (e.g. no tripod on suspended floors)

These affect scanning method, workflow and duration.

Potential access or visibility issues must be known early:

• Furniture blocking line of sight
• Storage areas
• Machinery and production lines
• Vegetation externally
• Restricted access zones
• Ceiling voids or roof spaces with no access
• Fragile or hazardous areas

If areas cannot be scanned, we clarify modelling assumptions in our deliverables.

We also require confirmation of:

Delivery Format

• SharePoint / OneDrive
• CDE (Asite, Viewpoint, Aconex, BIM360, Dalux)
• Secure link download

Delivery Deadline

• Required dates
• Staged deliverables (if applicable)
• Priority areas

Drawing / Model Standards

• Client-specific BIM execution plans
• CAD standards
• Title block requirements
• Naming conventions

We clarify:

• Who the primary contact is
• Who signs off scope
• Who approves LOD
• Who receives draft or sample outputs
• Whether weekly progress updates are required
• Whether design teams want review meetings or early model previews

Clear communication prevents delays and misalignment.

When client inputs are well-defined:

• Deliverables perfectly match requirements
• Costs are reduced and predictable
• LOD is correct for the intended purpose
• Survey teams capture everything required
• Modelling is efficient and accurate
• QA is smoother and faster
• No assumptions are made
• No rework is required

Many problems in BIM projects occur not because of poor modelling, but because the brief was not clearly defined.

Our structured input process ensures the opposite.

Return to the full Scan-to-BIM Survey Specification.

Tel: 07731 747329
Tel: 07928 653296
Email: info@towersurveys3d.co.uk