BIM Modelling Standards (BS 1192, PAS 1192-2, and the AEC (UK) BIM Protocol)

Without clear standards, BIM models become inconsistent, hard to use, unreliable and difficult to integrate into project workflows.

Our standards ensure:

• Predictable modelling behaviour
• Consistent naming and classification
• Accurate element placement
• Structured model breakdown
• Clear audit trails
• Seamless integration with design teams
• Compliance with client BIM requirements
• Output that matches LOD expectations

This level of structure is essential for projects involving multiple consultants or disciplines.

Our modelling framework takes guidance from key British standards and best-practice documents:

BS 1192 – Collaborative Production of Architectural, Engineering & Construction Information

We apply BS 1192 principles to support:

• Structured information exchange
• Consistent file naming
• Logical workset and work breakdown organisation
• Clear revision and responsibility protocols
• Coordinated shared coordinates

PAS 1192-2 – BIM Level 2 Delivery

PAS 1192-2 influences our approach to:

• Information Management
• Model purpose definition
• LOD / LOI clarity
• Common Data Environment (CDE) expectations
• Data validation prior to issue

AEC (UK) BIM Protocol for Revit

This protocol supports:

• Revit family standards
• Layer and category consistency
• Naming conventions
• Annotation standards
• View templates
• Workset organisation
• File structure and shared parameters

Our use of these standards ensures the models we deliver can slot directly into coordinated BIM workflows.

Before modelling begins, each file is structured to ensure performance, consistency and clarity.

Project Templates

We use a consistent internal template aligned to:

• Shared coordinates
• BIM naming standards
• Standard levels and grids
• Revit units and tolerances
• Preconfigured view templates
• Preloaded object styles and categories

Worksets

Worksets may include (depending on project size):

• Architecture
• Structure
• MEP (if included)
• Levels & Grids
• Shared Coordinates
• Point Cloud
• Links / CAD / Reference Files

This structure supports coordination and improves model performance.

Shared Coordinates

Shared coordinates are established early using:

• Survey control
• OS grid (if applicable)
• Client-provided datums
• Internal project geometry

All downstream models can be aligned reliably.

Correct naming ensures that models remain easy to navigate and integrate into design environments.

Element Naming

Follows the AEC UK standard and internal rules, covering:

• Families
• Types
• Instances
• Views
• Worksets
• Sheets

File Naming

Typically includes:

• Project code
• Originator
• Volume
• Level
• Type
• Role
• Number
• Revision

Example:
0863-T3D-ZZ-ZZ-M3-X-0001_P01.01.rvt

Shared Parameters & Metadata

Where required, we include:

• Classification codes (Uniclass 2015, IFC mapping, or client-specific codes)
• Material data
• Asset data (for FM/Asset Information Models)

Modelled from Point Cloud Only

No assumptions are made that are not visible in the point cloud.
Where ambiguity exists, we:

• Request clarification
• Highlight missing information
• Tag unclear geometry for review

Parametric Families

Revit families are:

• Built to reflect the visible as-existing size and shape
• Free from unnecessary detail
• Structured using Revit-native parameters
• Named and categorised correctly

Accuracy by LOD

Accuracy is driven by the Level of Detail required:

• LOD2: Massing-level with simplified geometry
• LOD3: 15–30 mm tolerance, accurate representation of major elements
• LOD4: 0–15 mm tolerance with high-detail geometry

The chosen LOD is documented at the start of the project.

We support a range of information levels depending on client requirements.

Typical LOI includes:

• Element type
• Materials
• Dimensions
• Fire ratings
• Asset tags
• System classifications
• Uniclass or IFC mapping

Where required, asset schedules or COBie-related fields can be included.

Architectural modelling adheres to strict geometric rules:

Walls

• Modelled to visible extents
• Thickness based on measured or inferred values
• Returns, offsets and openings accurately positioned

Floors & Ceilings

• Modelled as single planes unless stepped
• Slopes modelled where clearly visible
• Soffits accurately represented for coordination

Windows & Doors

• Dimensions taken from point cloud
• Mullions, rails and frames modelled according to LOD
• Openings cut to correct and measurable extents

Roofs

• Pitched and flat roofs accurately defined
• Parapets, gutters and upstands included at LOD3–4

Where structural modelling is required, elements include:

• Beams
• Columns
• Slabs
• Bracing
• Trusses
• Foundations (if exposed/visible)

Sizes and profiles are derived from point cloud measurements unless instructed otherwise.

For MEP LOD3+:

• Ducts, pipes and cable trays above an agreed diameter are modelled
• Plant and equipment volumes are captured
• Routing reflects visible as-existing conditions
• No hidden services are assumed

This supports coordination for refurbishment and retrofit projects.

Before issue, all models undergo structured QA checking:

• Conformance with naming standards
• Compliance with LOD and LOI requirements
• Element accuracy verified against the point cloud
• Workset and file structure review
• Family integrity review
• Final review by a senior modeller

Our ISO-aligned QA process reduces risk and ensures consistent quality.

Clients receive models that:

• Integrate easily with existing BIM protocols
• Follow UK-friendly conventions
• Are clean, organised and lightweight
• Support accurate measurement
• Improve coordination
• Reduce design errors
• Enable hassle-free downstream modelling

Professional standards = professional results.

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

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