Thomson - pioneer of sustainable architecture?

In the late 1860s, the Glasgow architect Alexander Thomson submitted to the city authorities a revolutionary proposal for improved workers' housing. New research and CAD techniques help to explain his ideas.

'Greek' Thomson is best known for his urbane Classical terraces in Glasgow and a handful of monumental, if stylistically promiscuous, churches. Yet he should also be known as a visionary who almost introduced into our vocabulary some of the essential elements of 'sustainable housing'. The argument hinges on an unrealized design Thomson prepared in 1868 for the Glasgow City Improvement Trust, an agency of the Town Council given the task of redeveloping a large area of slum housing centred on the medieval Old Town.

The Trust acting through the City Architect, John Carrick, invited Thomson and five other 'eminent local architects' to present designs for the reconstruction of different parcels of land along the spine of Glasgow's High Street. None of the proposals survives but Thomson's designs were described in detail in newspaper and journal accounts.(1) The dimensions given at the time and Thomson's paper on the project read to the Glasgow Architectural Society allow the design to be realized using modern computer graphic techniques.(2)

Thomson's proposals have particular relevance today in the UK where government predictions suggest that over 4 million new homes are required by 2016, mainly employing inner-city land. It was on such land that Thomson proposed creating, in a series of closely set parallel streets, a new community of over 10 000 people. (Slum clearances undertaken by the Improvement Trust demolished the homes of nearly 100 000 people between 1866 and 1900.) Thomson saw virtue in maintaining high densities in redevelopment in order to avoid displacement to the suburbs. He was not impressed by the suburban villa, terraced house or isolated tenement for workmen's accommodation: Thomson's design hinged upon cliffs of four-storey tenements arranged 'toast-rack' fashion across the rectangular city grid of Glasgow's central areas.

Density was essential, he argued, to maintain the economic vitality of shops and warehouses, and to justify the construction of property of value. Lower densities could not be squared with Thomson's monumental urbanism nor the creation of mixed-use neighbourhoods which he thought economically essential. At the time, there was pressure to reduce density of redevelopment to address the public health problems of cholera, typhoid and tuberculosis, especially after the Prince Regent's endorsement of model terraced housing at the Great Exhibition of 1851. But Thomson knew that high densities and sanitary health could be achieved by improving the design of the traditional Glasgow tenement and his proposal was intended as a demonstration. Public health, Thomson claimed in his paper, was a problem of layout and design, not of density. The population was to be housed in 112 tenements containing in total 124 shops and 2272 apartments. Each apartment was to house just over four people in rooms 10ft square and 9ft high.(3) The main departure from orthodoxy was Thomson's rejection of the perimeter block which had been Glasgow's preferred housing typology since about 1820 and one the City Architect had promoted as the best model for the redevelopment of the central slums. Instead, Thomson proposed building within the 'back green' or central courtyard employing closely spaced parallel tenements open at their ends to facilitate cross block ventilation.

The urban blocks in question (about 80 yards square) were to consist of alternate glazed and open streets lined by the continuous walls of four-storey tenements. Instead of having wide streets of equal dimensions on the orthogonal grid, Thomson proposed perimeter streets of unequal width (80ft, 60ft and 50ft) which he claimed would better promote city ventilation. The argument drew upon the advice of another Glasgow architect J. J. Stevenson (better known later as a pioneer of the Queen Anne style) who had observed that streets of different width heated in the sun differentially thereby promoting air currents which ventilated the buildings by drawing air from narrow enclosed spaces.

Thomson took the argument to its logical conclusion. He glazed alternate streets in the belief that the spaces would warm and be 'conducive to the health and comfort of all'. The glazed streets 32ft wide were in fact to be glass-covered malls four storeys high into which the tenements faced. The other parallel streets were to be unroofed service roads - unheated and hence providing the air source to purify the houses. The malls (or galleria) were left open at their ends but narrowed to 16ft, forming entrance gateways. Leaving the entrances open meant that Thomson did not have to provide roof ventilation. In effect, the glazed streets were to be spatially almost linear squares inviting entry but clearly belonging to residents.

There are many likely sources of inspiration for the proposal. The glazed arcades of the Great Exhibition of 1851 would have been familiar to Thomson, perhaps also he knew of the Galleria Vittorio Emmanuele II in Milan, begun just a couple of years earlier than Thomson's paper. Closer to home there was the glazed gallery in the Royal Scottish Museum in Chambers Street, Edinburgh by Paxton's collaborator Francis Fowke, built in 1861. But the important point for Thomson was that stack effect ventilation could be harnessed to promote the health of working-class people using the simple expedient of a lofty glass roof.

To allow air to move through the tenements, Thomson suggested brick construction incorporating ventilating flues placed parallel to the smoke flues. Each flue was to be separately routed to avoid the spread of contagious disease. Brick provided the economy and constructional flexibility Thomson required but, as the scheme was for the Town Council, some facade embellishment in stone was probably required.

The glazed streets had the advantage also of providing safe and healthy playgrounds for children under shelter and away from the coal and dust carts which ran along the other streets. Glasgow he noted was 'notorious for mortality amongst children' (Thomson himself lost four children in the epidemics) and the proposal placed health and play together in virtuous contact.

John Honeyman (Mackintosh's senior partner) chaired the meeting of the local architectural society at which Thomson's proposals were discussed. A group of members was established including engineers and ironfounders but nothing came of the idea. It was perhaps before its time. Looking today at the CAD reconstruction based on the dimensions he left us, it is surprising how modern the vision was.

There is the usual Thomson panache in street composition - an order which owes little to Greek precedent and much to a fertile Classical mind. The glazed roof, familiar today from the ubiquitous retail mall, was a revolutionary idea for workmen's houses in 1868, especially when justified on the grounds of health and solar gain. As Glasgow celebrates its Year of Architecture and Design one should not forget that Thomson has as much claim to proto-modernism as that other more famous Glasgow pioneer - Mackintosh.

1 For instance The Morning Journal, 17 March 1868 and The Builder vol 26 (1868), p234.

2 The CAD reconstructions were undertaken by doctoral student Vasileios Balampanos using AutoCad at the Department of Architecture, University of Huddersfield. The images were prepared as part of a television documentary on Alexander 'Greek' Thomson produced by Murray Grigor of Viz Productions for relay on BBC Scotland in June this year.

3 These were the minimum dimensions of room for four people to live and sleep in allowed by the 1862 Police Act. The height was unusually generous, but people slept in almost bunk-like beds one above another, with the parents usually on top. The police were empowered to visit and license tenements for the poor.