LVIA or TVIA: landscape and townscape compared

A landscape and visual impact assessment and a townscape and visual impact assessment share a methodology and differ in what they assess as the receiving resource. LVIA deals with landscape character and the effects of development on it, in rural and semi-rural settings. TVIA deals with townscape character, the built fabric, grain, streets and open spaces of an urban area. Both then assess visual effects on people, which is a separate exercise from the effect on the resource itself. Choose the wrong one for your site and you get an assessment that talks about field patterns on a site surrounded by terraced housing.

Both follow the third edition of the Guidelines for Landscape and Visual Impact Assessment, published jointly by the Landscape Institute and the Institute of Environmental Management and Assessment.

What each assessment covers

The visual half is the same discipline in both: identify who sees the development, from where, and how the view changes.

An LVIA and a TVIA will often carry the same structure, the same sensitivity and magnitude scales, and the same style of effects tables. The difference lies in the baseline and in the judgements about what character means in each setting.

Character in the two settings

Landscape character is usually well documented. National character areas, county level assessments and sometimes a local study give a published description you can work from, with key characteristics already identified. The assessor's task is to work out how the proposal affects those characteristics.

Townscape character is documented less consistently. There may be a conservation area appraisal covering part of the study area and nothing at all covering the rest. So townscape assessors spend more time building the baseline themselves, describing grain, plot rhythm, building lines, height patterns and the relationship of buildings to streets.

This has a practical consequence. A TVIA baseline that simply lists nearby buildings and their dates is not a character assessment, and a reviewer will say so. The baseline has to reach conclusions about what gives the area its character before it can assess a change to it.

Choosing viewpoints

In rural work, a zone of theoretical visibility is usually generated first, then viewpoints are selected to represent the range of receptors and distances within it. The list is agreed with the authority, and on larger schemes that agreement is recorded at scoping.

In urban work the theoretical visibility model is less useful, because intervening buildings dominate. Viewpoints are selected from streets, squares, bridges, park entrances and from designated views where the authority has adopted them. Kinetic sequences matter more than in rural work, because the experience of an urban view is usually one of moving along a street rather than standing still.

Agree the viewpoint list in writing before any photography. Nothing wastes more fee than a set of verified views from positions the case officer did not want.

Photomontage and verified views

The Landscape Institute's technical guidance on visual representation sets out types of visualisation, from simple annotated photographs up to survey-verified photomontages with recorded camera positions, focal lengths and control points.

Which type you need depends on the scheme and the authority. Tall buildings and schemes affecting heritage settings usually attract a requirement for the highest level of verification. Smaller rural schemes are often adequately served by annotated photographs and a wireline.

Do not let the visualisation type be decided at the end. Verified views require survey work, and retrofitting them to a set of photographs taken without control points means going back out.

Seasonality is the other trap. Summer photographs with vegetation in full leaf understate visibility, and authorities routinely ask for winter views. Plan the photography around that rather than around the submission date.

Sensitivity, magnitude and reporting effects

The guidelines set up a two-part judgement for every receptor and every character area. Sensitivity combines the value attached to the resource or the view with its susceptibility to the particular change proposed. Magnitude combines the size or scale of the change with its geographical extent, its duration and whether it is reversible.

The two are then brought together into a level of effect, and the assessor states whether the effect is adverse, beneficial or neutral.

Two things separate a defensible assessment from a weak one. The first is that every judgement is reasoned in words rather than produced by a matrix. Matrices are a presentational aid, and an assessment that hides behind one invites a reviewer to substitute their own scoring. The second is consistency: the same receptor type should not be highly sensitive in one table and of medium sensitivity in another without an explanation.

Report residual effects after mitigation, and be explicit about what the mitigation is and when it takes effect. Planting that screens a development in year fifteen does not reduce the effect at year one, and assessments that quietly assume established vegetation are the ones that get unpicked at appeal.

Cumulative effects deserve their own section where other consented or proposed schemes are in the same views. Agree the cumulative scheme list with the authority, because an assessment that omits a consented neighbour will be sent back.

Heritage interaction in townscape work

Townscape assessment and heritage assessment overlap and are not the same thing. The effect of a development on the setting of a listed building or on the character and appearance of a conservation area is a judgement under sections 66 and 72 of the Planning (Listed Buildings and Conservation Areas) Act 1990, and it carries a statutory duty that townscape character does not.

Keep them in separate documents with cross-references, or in clearly separated sections. A TVIA that absorbs the heritage judgement into a townscape effects table makes it harder for the officer to discharge the statutory duty, and harder for you to demonstrate that it was discharged.

The heritage statement should assess significance and harm in heritage terms, drawing on the visualisations the townscape work produced. Two documents, one set of images.

Which to commission for an edge of settlement site

This is the question the comparison actually turns on, and the honest answer is often both, in one document.

An edge of settlement site sits between two character types. Viewpoints from the open countryside behind it need landscape treatment. Viewpoints from the street frontage in front of it need townscape treatment. A single assessment that covers both, with a clearly explained study area and separate character baselines, is usually more useful than two documents that each ignore half the site.

Scope it with the authority. Ask directly whether they want landscape character, townscape character or both, what study area they expect, and which viewpoints. Get the answer in writing.

One honest caveat: the distinction between the two labels is less firm in practice than the terminology suggests, and some assessors use LVIA as a catch-all with townscape treated as a character type within it. That is defensible under the guidelines. What is not defensible is using a rural baseline for an urban site because the template was to hand.

To see how landscape and townscape documents fit alongside the rest of a major application pack, browse the report types by category.

For specialist technical reports, qualified professional input may be required. PlanScope provides AI-assisted draft reports for planning applications. Reports should be reviewed before submission. We do not guarantee planning approval.