Villa Muller: Adolf Loos and the Architecture of the Raumplan

In the Prague district of Stresovice stands one of the quietest radical houses in Europe. From the street, the Villa Muller is a plain white rendered cube, its windows placed with an irregularity that refuses any classical order, its surfaces unornamented and mute. Nothing about the exterior announces what is inside. That was the intention. Loos's own formulation was that the building should be dumb outside and reveal its wealth only within, and no building carries the idea further than this one. The house is a provocation in the form of a box.

Everything was spent on the inside, on the sequence, on the section.

The villa was designed and built from 1928 to 1930 and completed in the spring of 1930, for Frantisek Muller, an engineer and co-owner of the Kapsa-Muller construction company of Plzen, which specialised in reinforced concrete, and his wife Milada Mullerova. It was a fitting client for the commission: a builder of modern structures asking the most uncompromising architect of the day for a family house. Adolf Loos designed it in collaboration with the Czech architect Karel Lhota, who contributed to the design as Loos's health was poor. After completion, Loos celebrated his sixtieth birthday in the villa, in the rooms he had imagined as the fullest statement of his architectural thought.

The fullest expression of the Raumplan

The interior is the fullest built realisation of Loos's Raumplan, his theory of planning in three dimensions, and the reason the house matters far beyond Prague. Where conventional houses stack identical floors, the Raumplan treats the section of the building as the primary design problem. Rooms are placed at differing levels and given ceiling heights according to their function and importance: the principal spaces rise and expand, the intimate ones contract, and the rooms connect so that moving through the house feels continuous, a choreographed sequence of ascents and half-levels rather than a climb between storeys. Loos considered the villa the best example of his idea of spatial economy, and the claim is inseparable from the experience of the building. The plan cannot be read from the facade. It has to be walked.

This is architecture as route rather than as object. The visitor moves from the entrance through a progression of rooms that open off one another at slightly different heights, each space revealing the next, each threshold marked by a change of level, a change of material, a change of ceiling height. The effect is theatrical in the architectural sense: not decorated, but composed. The house teaches its own logic as you move through it, and by the time you reach the main hall you understand that the plain exterior was not modesty but strategy. Everything was spent on the inside, on the sequence, on the section.

A material world behind a blank wall

The material sequence is as deliberate as the levels, and it is the second half of the house's argument. The entrance lobby is clad in bright green glass tiles, a startling, almost aquatic threshold. The ante room is white panelled, a moment of calm. Then the large double-height main hall, running the width of the villa, opens up, partly covered in grey-green marble on walls, columns and horizontal surfaces, the stone giving the room its gravity and its cool light. A boudoir rises half a storey above, lined in yellow lemonwood, intimate and golden. The library is clad in dark mahogany panelling, the most enclosed and contemplative room in the house. General accounts of the interiors also cite marble, wood and silk among the materials.

Each room is given its own material world, and the transitions between them are part of the architecture. The marble of the hall is not the wood of the library; the green glass of the entrance is not the lemonwood of the boudoir. Loos understood materials as the true decoration of a building, and in the Villa Muller he deployed them with the precision of a jeweller. The garden, replanted to the original design by Loos with Camillo Schneider and Karl Forster, extends the composition outdoors. The house that is dumb outside is eloquent everywhere else.

Seizure, restitution and restoration

The Mullers lived in the villa for eighteen years, until the Communist takeover of 1948, after which the building was seized. In 1968, after Milada Mullerova's death, the most important fittings and collections were purchased by the Museum of Applied Arts and the National Gallery, and the villa was pronounced a Cultural Monument of the Czechoslovak Republic. The building then served as storage and a library, and later housed the Institute of Marxism-Leninism: a house built as an argument for the individual life, occupied by an institution built to deny it. The irony was architectural as well as political. The Raumplan, which treats each room as an individual with its own height and character, spent two decades as offices for a doctrine of the collective.

After the fall of Communism in 1989, the house returned to the Mullers' daughter, Eva Maternova. In 1995 she sold it to the City of Prague, which placed it in the care of the City of Prague Museum, and the Czech government declared it a national monument on 16 August 1995. Restoration planning began in 1997, and the restoration itself ran from 23 November 1998 to 25 May 2000, led by a team under Vaclav Girsa with the Loos scholar Burkhardt Rukschcio. It was a restoration conducted as research. Stripping back wallpaper and panelling revealed Loos's pencil notes and sketches on the walls, the architect's hand still present in the fabric. Furniture by Chippendale and Loos, pictures by Kokoschka, Corot and Chittussi, a Rodin sculpture and Persian carpets were retrieved from museum holdings and reinstated. The villa reopened as a museum in 2000, its rooms as close to their 1930 state as scholarship could make them.

The villa was pronounced a Cultural Monument of the Czechoslovak Republic in 1968 and declared a national monument of the Czech Republic by government decree of 16 August 1995. It is not inscribed on the UNESCO World Heritage List, and it must not be described as such; it appears in Czech tentative-list promotion and in a proposed extension of the Prague World Heritage site, which is a different status entirely. The villa closed for a technical renovation in February 2025. Readers planning a visit should confirm current arrangements with the City of Prague Museum, which administers the house. Behind its blank white walls, the fullest realisation of the Raumplan waits, dumb outside and eloquent within, exactly as Loos intended.

The section as the plan

Most houses are designed in plan: rooms arranged on a sheet, stacked floor on floor. The Villa Muller was designed in section. Loos thought first about heights, about the vertical relationships between rooms, about how a half-level here and a double-height space there could make a house of modest footprint feel expansive and varied. The ceiling heights are set by the importance of each space, which means the architecture tells you what matters simply by how it rises or contracts around you. It is a social theory built in concrete and marble: the main hall is grand because gathering is grand; the library is low and dark because reading is intimate.

Karel Lhota's contribution, made as Loos's health was failing, is part of the house's story too. The villa is Loos's conception and Loos's Raumplan, but it was realised through a collaboration, and the building stands as evidence that even the most individual architecture is a collective act. The pencil notes and sketches found on the walls during the 1998 to 2000 restoration, revealed when wallpaper and panelling were stripped back, are the most direct trace of that act: the architect's hand, thinking on the wall itself.

A monument, not a relic

The villa's heritage status reflects a country still deciding how to value its modern past. Pronounced a Cultural Monument of the Czechoslovak Republic in 1968 and declared a national monument of the Czech Republic in 1995, it sits in the serious company of the nation's protected buildings. Its appearance in Czech tentative-list promotion for UNESCO, and in a proposed extension of the Prague World Heritage site, signals an ambition that has not yet become an inscription, and the distinction matters. Tentative status is a promise, not a prize. The house does not need the prize to matter; the Raumplan was influential without it, and the building's importance was settled by architects long before any committee voted.

Closed for a technical renovation in February 2025, the villa is a working museum rather than a frozen one, and its custodians at the City of Prague Museum continue the conservation work that the 1998 to 2000 restoration began. Behind the dumb white exterior, the marble hall, the lemonwood boudoir and the mahogany library wait for the next visitor to walk the section Loos drew. The house remains what it was in the spring of 1930: the fullest realisation of an idea about how rooms, heights and materials can compose a life.