What Are Verified Views?

A photorealistic render is sometimes assumed to be a verified view simply because it looks convincing. A simple wireline overlay, by contrast, can appear less substantial because it shows little more than an outline. Neither assumption is correct.

What makes a view verified has very little to do with how finished it looks. An Accurate Visual Representation, or AVR, is verified through the process behind it: a recorded camera position, survey information, an accurately positioned 3D model and a documented methodology that allows the result to be understood and checked.

Photorealism comes later. It determines how much of that verified geometry is rendered and how the proposal is represented visually. The distinction between what an image shows and how reliably it has been produced is fundamental to understanding Verified Views.

1 | What Makes a View "Verified"

The London View Management Framework defines an AVR as an image that shows the location of a proposed development as accurately as possible and is prepared using a well-defined and verifiable procedure.

The emphasis is on the process rather than the appearance of the finished image.

In practice, this means combining a photograph taken from a known and recorded position with an accurately scaled 3D model of the proposal, positioned using survey and other spatial information. The methodology should be documented clearly enough for another practitioner to understand how the image was produced and, where necessary, check the alignment.

An image produced in this way can be verified whether it is presented as a simple wireline or as a fully rendered photomontage.

This is why a wireline, or photowire, should not be thought of as a lesser version of a rendered image. Where a proposal is substantially screened, for example, a wireline may actually communicate the relevant information more clearly. It can show the position and extent of development behind buildings or vegetation, helping to establish what would be visible and what would remain concealed.

A wireline and a rendered AVR simply answer different questions.

2 | Why Planning Decisions Rely on Them

Planning officers, committee members and consultants assessing a major development often need to understand spatial relationships that cannot be fully communicated through plans, elevations or a Design and Access Statement alone.

How does the proposed massing relate to the surrounding townscape? Does it interrupt an established skyline? Would it be visible within a protected view? How does it affect the setting of a listed building, conservation area or World Heritage Site?

Verified Views provide visual evidence to help answer these questions.

Because the camera position, 3D model and photographic alignment are based on recorded information, the viewer does not have to rely solely on an artist's interpretation of how the development might appear.

That does not remove professional judgement from the assessment. The significance of a visual, townscape, landscape or heritage effect still needs to be considered by the relevant specialists. The role of the Verified View is to provide a reliable visual basis for that assessment.

It is not intended to persuade a planning committee that a development looks attractive. Its purpose is to represent the position, scale and visibility of the proposal as fairly as possible from the selected viewpoint.

3 | When a Verified View Is Required

TGN 06/19 sets out four Visualisation Types, ranging from an annotated viewpoint photograph at Type 1 to highly accurate and verifiable photomontages or photowires at Type 4.

The appropriate Visualisation Type should be proportionate to the purpose of the assessment, the sensitivity of the receptor and the likely visual effects of the proposal. Where possible, the approach should be discussed and agreed with the relevant planning authority or consultants.

There is no single rule stating that a particular type of development must always use a particular Visualisation Type.

In practice, however, the highest levels of accuracy and verifiability are often appropriate for projects where relatively small differences in position, scale or visibility could materially affect the assessment. These can include tall buildings, developments within sensitive heritage settings, proposals affecting conservation areas or listed buildings, schemes within or affecting World Heritage Sites, and developments affecting strategic or protected views.

Formal TVIA, LVIA or EIA work may establish the required approach for individual viewpoints as part of the scoping process. The viewpoints themselves are commonly identified by the townscape, landscape or heritage consultant and, where appropriate, discussed with the Local Planning Authority and other relevant consultees.

4 | Verified Views Compared with Marketing CGI

A Verified View and a marketing CGI may both ultimately appear as two-dimensional images of a proposed building within its surroundings, but they are produced for very different purposes.

Photorealism is not what separates the two.

A marketing CGI can be completely photorealistic without being verified. Equally, a simple wireline can be produced using a fully controlled and verifiable process.

The distinction lies in how the camera, model and existing context have been established and whether the process can be understood and checked.

For a fully rendered AVR, however, visual quality remains important. Once the position and geometry of the proposal have been established, its architecture, materials, glazing, landscape and character should be represented as faithfully as the available design information allows.

5 | How a Verified View Is Produced

The production of a Verified View generally follows a defined sequence.

Viewpoints are first identified and, where appropriate, discussed or agreed with the Local Planning Authority and relevant consultants. Baseline photography is then captured from each viewpoint using an appropriate camera and lens specification.

The camera location and suitable features visible within the photograph are recorded using survey techniques appropriate to the project. These surveyed features provide spatial references that can be used to position and check the virtual camera and proposed development.

The 3D model is then placed within the same coordinate system and a virtual camera is aligned with the photograph. The model can subsequently be rendered to the agreed AVR Level and composited into the baseline image.

The process is recorded in a methodology statement explaining how the photography, survey, camera matching and image production were carried out.

Survey accuracy needs to be considered in relation to the particular view. A relatively small error in camera position can have a much greater effect when the subject is close to the camera than when it is several kilometres away. TGN 06/19 therefore takes a proportionate approach rather than prescribing one survey accuracy for every situation.

The choice and distribution of control points also matters. Useful reference points might include building corners, window heads, rooflines, kerbs or other clearly identifiable features distributed across the photograph and at different distances.

A good spread of information helps constrain the camera match and provides a stronger basis for checking the alignment than a cluster of points concentrated within one part of the view.

6 | AVR Levels and Visualisation Types Are Two Different Scales

AVR Levels and Visualisation Types are often confused, but they describe two different things.

AVR Levels 0 to 3 originate from the London View Management Framework. They describe how much information about the proposed development is shown in the finished image.

At AVR0, the image establishes the location and overall extent of the proposal. AVR1 adds information about its visibility and occlusion. AVR2 communicates the architectural form in greater detail, while AVR3 represents the proposed materials and appearance.

Visualisation Types 1 to 4, as set out in TGN 06/19, relate instead to the method used to produce the visualisation and the level of accuracy and verifiability appropriate to its purpose.

The two classifications therefore work alongside one another rather than forming a single scale.

A view might, for example, be produced using a Type 4 methodology and presented at AVR Level 1 as an occluded wireline. This could be appropriate where the main purpose is to establish how much of the proposal would be visible rather than to assess its materials.

Equally, the same verified geometry could be developed into an AVR3 where the appearance, materials and architectural character of the proposal also need to be considered.

Terms such as "AVR Type 4" or "LVMF Level 4" mix the two systems together and should be avoided.