Trompe l'oeil (part 2)
![]() |
Would you walk over this bridge? |
In architecture, trompe l’oeil (Brit. pronunciation tromp-loy) describes visual effects designed to intentionally create an optical illusion. The term comes from the French meaning ‘to deceive the eye’. The aim of such effects is to make things seem what they are not, for example, to make things appear bigger, longer, shorter, more expansive, and so on. The viewer may or may not be aware that what they are observing is a deception.
Such techniques can be used to satisfy aesthetic requirements or address a design’s limitations, (such as making a very small space appear less claustrophobic or, in interior decorating, painting a mural or applying wallpaper to give the viewer the impression of a window with a pleasant view. Sometimes architects and artists use trompe l’oeil to inject light-heartedness into an otherwise serious composition.
Artists throughout history have used trompe l’oeil. It was used to trick the observer into believing that what is depicted on a two-dimensional surface is actually three dimensional. Many cities have striking modern murals that achieve this effect, although the ‘reality’ may depend on where the viewer stands.
[edit] A few case studies
![]() |
The entasis on the upper parts of the Doric columns (left) is just about discernible. |
Architects may use trompe l’oeil to correct a natural phenomenon. The ancient Greeks, for example, added entasis to the columns of the Parthenon and other temples to correct the natural ‘appearance’ (to the naked eye) of columns buckling or bowing – which was considered an illusion of weakness. By splaying the columns almost imperceptibly inwards at their upper reaches (in other words decreasing the column diameter) the result is a column with convex sides, that gives, paradoxically, an illusion of straightness and so of ‘solidity’ and ‘strength’.
Later, in the Baroque period, the 17th century architect and sculptor Gian Lorenzo Bernini who designed the colonnades on either side of St Peter’s Square, Rome, created a design of immense proportions (1656-1667). To give the visitor the effect of an embrace in the “maternal arms of the Mother Church”, the colonnades on either side of the square are splayed outwards in the direction of the basilica. On approaching the basilica, the visitor does not perceive the usual natural perspective of lines converging to a vanishing point. Instead, the diverging colonnades look to be parallel, an optical illusion that makes the basilica appear closer to the viewer than it actually is. Leaving the basilica, the effect is reversed as the exaggerated perspective of the converging colonnades results in significant foreshortening.
Another optical effect of note is that when standing in the middle of the square, the observer perceives the colonnades on either side (284 columns in total) to be just one column deep; in reality, they are four-columns deep.
In 17th and 18th century Britain, one of the applications of trompe l’oeil was for reasons of aesthetics, economy and practicality: the use of polished plaster on walls and columns gave a highly-realistic impression of marble or travertine, creating an illusion of depth and texture, without requiring the stonemason’s craft – and at a fraction of the cost. Polished plaster was first used by the ancient Egyptians and extensively in Venetian palaces of the Renaissance and Baroque periods. It is still in use today throughout the world.
See also: Trompe l’oeil part 1
[edit] Related articles on Designing Buildings Wiki
Featured articles and news
Great British Energy install solar on school and NHS sites
200 schools and 200 NHS sites to get solar systems, as first project of the newly formed government initiative.
600 million for 60,000 more skilled construction workers
Announced by Treasury ahead of the Spring Statement.
The restoration of the novelist’s birthplace in Eastwood.
Life Critical Fire Safety External Wall System LCFS EWS
Breaking down what is meant by this now often used term.
PAC report on the Remediation of Dangerous Cladding
Recommendations on workforce, transparency, support, insurance, funding, fraud and mismanagement.
New towns, expanded settlements and housing delivery
Modular inquiry asks if new towns and expanded settlements are an effective means of delivering housing.
Building Engineering Business Survey Q1 2025
Survey shows growth remains flat as skill shortages and volatile pricing persist.
Construction contract awards remain buoyant
Infrastructure up but residential struggles.
Home builders call for suspension of Building Safety Levy
HBF with over 100 home builders write to the Chancellor.
CIOB Apprentice of the Year 2024/2025
CIOB names James Monk a quantity surveyor from Cambridge as the winner.
Warm Homes Plan and existing energy bill support policies
Breaking down what existing policies are and what they do.
Treasury responds to sector submission on Warm Homes
Trade associations call on Government to make good on manifesto pledge for the upgrading of 5 million homes.
A tour through Robotic Installation Systems for Elevators, Innovation Labs, MetaCore and PORT tech.
A dynamic brand built for impact stitched into BSRIA’s building fabric.
BS 9991:2024 and the recently published CLC advisory note
Fire safety in the design, management and use of residential buildings. Code of practice.