Short answer
Mostly they did not decide at all: regional building colour came from local earth, stone, lime and timber, which is why a region's façades often share a palette. Colour surveys such as Jean-Philippe Lenclos's 'geography of colour' set out to record those palettes, and since the late 1970s many Italian towns have adopted formal colour plans to protect them — while in England exterior repainting is normally permitted development unless a local authority has removed that right.
Before industrial paints and cheap transport, the colour of a building was largely the colour of what it was made from and what it was finished with: the local clay fired into brick or tile, the local stone, lime-wash tinted with whatever earth pigments were to hand, and timber left to weather. That produced regional families of colour — the ochres and siennas of Tuscan render, the grey granite of Aberdeen, the red sandstone of parts of the English Midlands — that visitors read as the character of a place. It is a material and economic story before it is an aesthetic one, and it explains why a colour that looks right in one landscape can look imported in another.
The French colourist Jean-Philippe Lenclos, born in 1938, developed the idea of a 'geography of colour': that the colours of a region's buildings could be surveyed systematically — sampling render, shutters, doors and roofs, and recording them as swatches and paintings — and used to guide new work. His books documented French regions and then the wider world, including Couleurs de la France (1982) and Couleurs du monde (1999), published in English as Colors of the World in 2004. The method treats colour as a measurable property of a place, which is what makes it usable in planning, although what the surveyor chooses to sample remains a judgement.
A colour survey records the palette as it is now, including recent repaints. Deciding which of those colours are 'authentic' is an interpretive step that surveys alone cannot settle.
Italy turned surveys into regulation. From the late 1970s, Italian municipalities began adopting piani del colore — colour plans — that combine historical research into façade finishes with a palette and rules for repainting, so that renewal does not gradually replace a town's character with whatever paint is in fashion. Giovanni Brino's survey of Italian city colour plans covers the period 1978 to 2007, and recent research, such as a 2022 study of the colour plan for the Egadi Islands off Sicily, describes these plans as tools for managing the image and identity of a place against homogenising pressures. They are cultural policy: they protect a recognisable appearance, not a measurable performance.
In England, painting the outside of a building is normally permitted development under the General Permitted Development Order 2015, which defines painting as any application of colour; only painting for advertisement, announcement or direction is excluded. That default can be removed. A local planning authority can withdraw permitted development rights with an article 4 direction — commonly used in conservation areas — or by a condition on a planning permission, and a listed building may need consent for a change that affects its character. So the same repaint can be free in one street and require permission in the next. Check with the local planning authority; this page describes the framework and is not planning advice.
A façade is seen with its neighbours, its roof, the sky and the street surface, and at a distance where fine detail and small colour differences disappear. Strong chroma that looks lively on a swatch becomes the loudest thing in a terrace; very light colours read as brighter than expected in full sun, and very dark ones absorb more solar heat, which matters for render and timber movement as well as for comfort. Rules of thumb used by conservation officers — keep large areas muted and let doors and joinery carry stronger colour — are aesthetic conventions, not physics, but they reflect how viewing distance and neighbouring surfaces change what a colour looks like.
Why: Large areas seen in daylight look lighter and more saturated than a small sample indoors, and the neighbours change the context.
Fix: Test a large panel on the actual wall, view it from across the street at different times of day, and compare it with adjoining façades.
Why: An article 4 direction in a conservation area has withdrawn the permitted development right to paint.
Fix: Check the local authority's conservation area and article 4 information before repainting.
Each statement is labelled by kind — established fact, a standard’s requirement, observed market data, a convention, or Colourwise’s own interpretation or analysis — with the strength of the evidence behind it.
FactModerate evidence
Jean-Philippe Lenclos, a French colourist born in 1938, developed the concept of a 'geography of colour' and published regional colour surveys including Couleurs de la France (1982) and Couleurs du monde (1999), the latter in English as Colors of the World (2004).
FactModerate evidence
Italian municipalities have produced formal city colour plans since the late 1970s; a survey by Giovanni Brino covers plans from 1978 to 2007.
Source: Italian City Colour Plans (1978–2007), in Colour for Architecture Today
ConventionModerate evidence
Colour plans are framed in recent planning research as tools for protecting a place's urban image and identity against homogenising change, rather than as measures of environmental performance.
StandardStrong evidence
In England, painting the exterior of a building is permitted development under Class C of Part 2 of the 2015 General Permitted Development Order, except painting for advertisement, announcement or direction, and 'painting' includes any application of colour.
FactStrong evidence
Local planning authorities can remove permitted development rights by an article 4 direction or by a planning condition.
Source: Planning practice guidance: When is permission required?
Reviewed 29 September 2026. Colourwise summarises its sources in its own words and does not reproduce standards text or proprietary colour data. Spotted an error? Tell us.