ENERGY RESEARCH, VOL. 10, 101-120 (1986)

THE PASSIVE SOLAR HEATED SCHOOL IN W-ALLASEY. I

FOREWORD AND INTRODUCTION

M. G. DAVIES Department of Building Engineering, The University of Liverpool, Liverpool, U . K .

SUMMARY

St. George’s School, Wallasey, situated in the U.K. at latitude 53.4” N was designed so that equitable thermal conditions should be achieved within it using solar gains, heat from the lighting system and body heat from the children without the use of a conventional heating system. The building opened in 1962 and evoked considerable comment, both favourable and unfavourable, in the mid-sixties. This article briefly notes some of the comments and provides an account of some of the features which the architect incorporated to control the solar gains that enter through the large south-facing solar wall. Later articles in this series describe the findings of observational surveys carried out in the building.

KEY WORDS Solar heating Passive solar design Control of solar gains

FOREWORD

It is unusual for a learned journal to publish a series of articles treating a single topic, in this case a building and its energy needs. Some justification for the eight articles on the Wallasey School seems needed.

First, there is the building itself with its huge glazed south wall, very photogenic, an object of mystery in its earliest years, seemingly conjuring heat out of the air. It was completed in 1961, more than a decade before terms such as ‘passive’ and ‘energy conscious design’ came to be used. It was much visited and opinions were diverse. Some believed that the heating was totally provided by ambient energy which was sufficient to achieve satisfactory thermal comfort, even in the very cold winter of 1963. Others noted the increasing frequency during the 1960s of environmental complaints from the occupants of buildings with large glazed areas; they could be excessively cold in winter and unbearably hot in summer. The Wallasey School was suspect generally on these grounds and more specifically since some visitors objected to the odour level in the building-the odour was seen as part of the solar heating package. Interest in the building eventually waned somewhat but was re-awakened in 1975 after an account was given at the International Solar Energy Society’s conference in Los Angeles. It then became regarded as a forerunner of the solar houses then being built in the south-west of the U.S.A.

Secondly, the personality of the architect Emslie A. Morgan thrusts itself forward: his evident force of character in persuading his local authority and the Ministry of Education to allow such a building, largely dispensing with a heating system, and without the support of any figures to substantiate his claims; his audacity in patenting the scheme and his rugged ability to turn his hand to all aspects of design--conceptual, structural, electrical, control, materials, financial and evaluation. Then there was his tragic and premature death in 1964.1 never met him but many of the staff I met when I first became involved in the project and who had known him, most notably the headmaster and caretaker, were devoted to his memory, to his principles and to the care of his building. They were determined to ‘make it work’, as the caretaker put it. Furthermore, it was often said that the architect’s secrets died with him; it is widely known that a set of notebooks survived him but nothing of the substance of their content has ever emerged.

Thirdly, a passive building fluctuates in temperature and this thermal behaviour invites, indeed forces, the

0363-907X/86/020101-20$10.00 0 1986 by John Wiley & Sons, Ltd.

Received 20 January 1985

102 M. G. DAVIES

investigator to devise a thermal model which includes consideration of a variety of heat transfer mechanisms. The Wallasey School is probably the first passive building to have been thermally modelled in this way. Historically, the investigation on the school was happily timed. During the 196Os, the team of workers at the Building Research Station (BRS) had fashioned a range of procedures for handling solar gains, heat exchange within a space and heat storage in the walls. Their publication of these techniques fell about the same time as the start of my own involvement with the school and their work formed a s!arting point for my thermal modelling.

Fourthly, the physical observational study we conducted enabled a parallel investigation to be conducted on the degree of satisfaction that the children felt for their thermal environment.

As far as I am aware, Morgan never made contact with the then recently founded Department of Building Science in Liverpool, about 7 miles from the school. After Morgan’s death, Professor A. Hendry wrote a short report on the building, and a group of workers in Liverpool, already engaged on thermal matters generally, formally undertook a small scale and, later, a larger scale investigation on the building supported by the Ministry of Public Buildings and Works (MPBW). Various workers left and joined the team. My own involvement dates from 1967, when the measuring equipment was installed in the school but was not yet operational.

The array of transducers was large by the standards of the day, and this, together with problems of staffing, access to the building, faulty items of equipment and other difficulties allowed only very slow progress. The bulk of the physical measurements were made between January 1969 and July 1970. The recordings were stored on 8-hole paper tape, and processed in due course by the University computer and all substantive analyses were subsequently made by hand; inspection was always necessary to correct or reject faulty data. The Research Assistant supported by the MPBW/Department of the Environment left in 1971 and the project had no further external support.

Thus in 1971 I was faced with the problem of selecting and handling data manually from more than 2 million recorded values of temperature etc., with only limited clerical assistance. There were some major problems concerned with the thermal modelling of the school itself. Could one, using the methods of the day, model the complexities of the solar wall? What could be learned of the thermal behaviour of the building in the complete absence of any measure of ventilation rate, or of knowledge of convective heat transfer coefficients, which it was recognized could be low in still conditions. Furthermore, I felt that there were more general conceptual problems concerned with the logic underlying the ‘environmental temperature procedure’ as it had been advanced by the BRS team; the procedure would otherwise have provided an appropriate means of modelling the building.

The course of action I had to take was suddenly made very clear by the oil crisis in 1973. The Department of the Environment (D.0.E.) required its final report on the building as quickly as possible and without regard for conceptual difficulties. I therefore collected together a quantity of factual material found from the observational survey, prepared an account of the model study work on periodic and transient response, and also on what I then knew of energy iequirements in the presence of sizeable passive gains. This constituted the final report and was sent to the D.0.E. in 1974. I did not regard it as suitable for publication at that stage.

However, the production of the D.0.E. report freed me for the time from the obligation to process Wallasey data and I went on to consider some theoretical issues in depth. The work lasted some years and has resulted in publications grouped round the subject areas of heat exchange within an enclosure, the response of walls and enclosures to diurnal and to transient excitation, to the energy needs in a room where solar gains may contribute significantly to the heat need, and to the problem of including moisture movement and condensation in thermal modelling.

Some of the work was undertaken partly with the Wallasey School in mind. In particular, I resolved in the light of information available about the school and the facilities available to me what could and what could not be learned from the data. I eventually took up the Wallasey project again with a view to publication.

The series consists of eight articles, I-VIII. Article I summarizes the earliest reactions to the building, its energy needs and the comfort it provided, and includes Reyner Banham’s perceptive comments. I had long wondered what the architect knew or might have known about the technology of passive solar building when he designed the school in the late 1950s. Article I1 examines the background; it summarizes the consideration

THE PASSIVE SOLAR HEATED SCHOOL IN WALLASEY. I 103

the architect gave to certain energy-conserving devices and provides a guide to the Patent Specification. 1 suspect, though I cannot prove, that Morgan placed his confidence in an undisclosed report on window energy balance.

Article 111 summarizes the work done to estimate how the fabric of the building might respond when subjected to steadily applied excitation, strong daily sunshine (by summing the responses of 10 harmonics), and to the weak but important effects of switching lights on and off-the main source of heating in winter. Article IV, based on the mass of observational material, examines what such steady, periodic and transient responses actually were; it reports values for long and short response times for a classroom (using autocorrelational analysis) and appears to demonstrate the suspected low convective heat transfer coefficient.

The fifth article-V-makes use of 50 years of air and sunshine data, fortunately available for a site very close to the school. It suggests that solar gains should be beneficial, if only to a modest extent, with a construction similar to that of the school, and on that site. The article also presents information about electricity consumption and costs, which show that the school fuel costs seem to be low in relation to national figures.

We conducted user surveys on the children in the school (article VI). These demonstrate that the building provides for the most part a satisfactory standard of warmth and that the environment is not noticeably different in its main subjective characteristics from other more usual constructions. It goes further than previous surveys however in demonstrating quantitatively that the children actively engage in minimizing their thermal discomfort. One aspect of this is taken up in detail in the seventh article (VII) where the immediate physical conditions that lead to opening and closing windows-an important feature in the architect’s design-are examined.

Finally, since we did not conduct a survey of the lighting in the early investigation, a colleague has recently examined this aspect (article VIII).

INTRODUCTION

The building behind the expanse of glass to be seen across the fields from the mid-Wirral motorway, St. George’s School, Wallasey, has three claims for inclusion in an account of post-war U.K. architecture. It was completed in 1961 and has been in normal use since; as such it may well be the oldest building in the world in current use which was explicitly designed so as to make use of passive solar gains. Secondly, being designed to house 300 pupils, it is very probably the largest in the world, and certainly the largest in the U.K. Thirdly, at a latitude of 53.4”N, it functions considerably further north than the majority of solar houses.

It is provided with a conventional hot water central heating system, but the system is seldom used. It attracted considerable attention in the early 1960s by its ability to maintain an equitable temperature without conventional heating. The heat is provided by solar gain through its near 100 per cent glazed wall which faces a little west of south, together with heat from the tungsten lamps; body heat contributes significantly to the heat need.

The architect Emslie A. Morgan, Assistant Borough Architect to Wallasey Corporation, intended that the control of the environment should be effected by the occupants, who could switch lights on to heat the building, and open the large and convenient windows and ventilators to cool it.

The architect monitored its performance for a while after it opened in 1962 but unfortunately he died in 1964, having made no public statement about it. He was in the course of patenting the design, and the Patent Specification appeared in 1966 (Morgan, 1966).

The building evoked a range of descriptions and opinions, most of them ill informed, misleading or not based on observation or reasoning: ‘Strict secrecy still veils the technical details of the new heating systems- run on sunshine and a few shillingsworth of electricity-. . .’ (Lioerpool Daily Post, 19 July 1963); ‘Solar radiation, which is a natural form of heating, is present whatever the weather. A solar system is not dependent on sunshine and is therefore just as effective in winter as in summer’ (The Municipal Journal, 31 January 1964, p. 333); ‘The design (of the school) . . . has proved to be the ultimate example of “environmental design.” For several years now the school has had no heating bills . . .’ (Insulation, May 1967, p. 117); ‘Although in winter,

1 04 M. G. DAWES

when there is little sun and outside temperatures are low, the solar wall is a source of some heat loss, at other times it receives enough radiation to give an overall gain in heat to the building’. (Building, Lighting, Engineering, an Australian magazine, September 1967, p. 38); ‘St. George’s School . . . is heated entirely by solar energy,’ (Journal of Fuel and Heat Technology, March 1967, p. 35); ‘An official of Wallasey Corporation said,“I think a lot of people had doubts whether it would work when it was first built, but it has turned out to be a complete success. All sorts of people have been here and tried to fault it but the fact remains that it works. The staff and pupils are perfectly happy with it and it has now stood up to the test of several winters, including the severe one of 196243 when it was the only school in the borough where there were no heating problems”.’ (The Times, 5 January 1967); ‘Warming the seats of their pants the whole year round are boys of St. George’s School . . . the first (building) to put into practice some new ideas which Mr. Morgan . . . called “Solar heating” . . . The experiment has been so successful . . . All parts of the building are kept at an even temperature of 64°F.’ (She, October 1969).

The architect himself would say nothing publicly about the physics of his heating system because of his application for a patent for the system. Since the following article apparently quotes him verbatim, it is worth reproducing in fuil:

Solar Heating Cuts Costs The Solar heating system installed last year in St. George’s Secondary School, Wallasey, Cheshire

has proved itself to be more efficient and 68 percent cheaper to use than conventional methods. Comparative costs have now been worked out by Mr. Emslie Morgan, principal assistant in the

borough architect’s department of Wallasey Corporation-the man who has harnessed and stored the heat provided by the rays of the sun.

Mr. Morgan is currently engaged in arranging world-wide patent rights to cover his invention, the scientific basis of which he is still keeping a close secret.

In making his conclusions available for B.I.N., Mr. Morgan emphasised that his figures are not an exact comparison with the cost of orthodox heating installed in a sister school to St. George’s, but merely the best and most precise available at this time. [Mr. Morgan went on to say:]

‘A certain amount of electricity is used in connection with my solar heating system,’ he went on, ‘but this is not separately metered and is not, therefore, easily computed. For the moment, the simplest comparison is with the sister school, which occupies part of the same site, and accommodates 300 pupils-the same as St. George’s School. It was built 8 years ago and has hand- fired coke burning boilers and hot water radiators.

‘In terms of annual costs from April, 1962 to March, 1963 the solar heated school involved an expenditure of E598 on electricity for lighting and power, but nothing had to be spent on coke for heating and domestic hot water. Oil used for domestic hot water only, cost El 12, making a total of E7 10.

‘Electricity used during 2 summer quarters covering the period from April to September, 1963 cost El53 and all these figures apply of course, to the portion of the building required for solar heating.

‘When we turn to the sister school, we find that electricity for lighting and power cost E447. No oil was needed which means that the total overall expenditure reached El ,266. Electricity consumed during the April-September period of 1963 cost E156.

‘Therefore the annual saving achieved in the heating of the solar school is L1,266 less E710, which works out at E586. This represents an annual saving of 68 %.

‘On the question of efficiency, I can only say that my system stood up splendidly to the demands the severe weather of last winter made on it.

‘Teachers and pupils alike confirmed that they were warmer and more comfortable in the solar school than those in the sister school. When the winter ended we found that my system still had a big advantage in efficiency over conventional heating, because by controlling the inside heat in relation to the temperature outside the class rooms were cooler when the weather was warm and warmer when the temperature fell.

‘This result was achieved by using the solar wall which is a fundamental feature of my system.’ (Building Industry News, 19 December 1963)

THE PASSIVE SOLAR HEATED SCHOOL IN WALLASEY. 1 10s

Judgements on the building clearly hung upon the meaning of ‘success’. Popular opinion and later objective measurements agreed that satisfactory thermal working conditions could usually be maintained in the building. The question as to whether the solar wall, which permitted large losses of heat by night really led to a net saving in energy, was never discussed objectively. Even the carefully reasoned article by Hammond and Trubshaw (1968), only alludes to this vaguely near the end. (The question had in fact been posed explicitly and answered by Billington in 1947, but this important paper had been forgotten by the 1960s. It isdiscussed in the second of these articles.)

On the other hand a solid body of opinion was ranged against the building. It noted that summer overheating had occurred in many post-war buildings with large glazed areas; overheating was undesirable; the Wallasey School had a large glazed area; therefore the Wallasey design was undesirable. (In fact the large thermal storage very much restricts rises in temperature in sunny summer conditions.) Again visitors noted and disapproved of the odour levels in the building; the odour was mainly associated with the preparation of school dinners; the staff and pupils did not find this objectionable; indeed the Headmaster flatly denied that any odour existed there at all. Furthermore, visitors when staring at the solar wall might be troubled by glare; the staff and pupils, who were normally engaged upon desk tasks, were not normally upset by any problems of glare.

It was apparent by the mid 1960s that the school presented a building of considerable interest from the point of view of its temperature response and in regard to the environment it provided for its occupants. (The question of its effectiveness in saving fuel became formulated later.)

In the mid-1960s Dr. C. B. Wilson of the Department of Building Science in Liverpool University-some 7 miles from the school-had undertaken work of a general kind on the thermal response of buildings with the support ofa contract with the Ministry of Public Buildings and Works. In view of the mystery enshrouding the thermal working of the school following the death of the architect, it was decided that the contract should include an investigation of the thermal response of the school. Some temperatures were first recorded by chart but they proved difficult to analyse. Dr. Wilson, together with Mr. E. R. Hitchin, then installed a 50 channel data logger and recorded physical data, mainly temperatures, in and around an upstairs and downstairs room in the building.

Dr. Wilson left Liverpool in 1966 and the present author took over responsibility for the project in January 1967. I’ylr. Hitchin left later that year. A further contract with the MPBW/Department ofthe Environment was arranged and Dr. N. S. Sturrock assisted from 1969 to 1971. The final report on the project was prepared during 1974 but was not published in full because of some technical uncertainty.

The building continued to evoke some mild interest among U.K. workers, but international interest was awakened after the author described it at the Solar Energy Congress in Los Angeles in 1975. It was then recognized as a building similar to a number of solar houses that had been built in the early 1970s in the south- west of the U.S.A. The term ‘passive’ had become attached to such building forms, together with a new vocabulary to describe their features.

The results of the Liverpool investigation are now to be presented in a series of articles. The present article deals mainly with the physical construction of the school, and the following article with an account of the architect’s preliminary thinking and the Patent Specification. The third and fourth articles are concerned with the temperature response of the building and the fifth with its energy needs and running costs. The sixth (with Dr. Ann D. M. Davies) gives the results of a longitudinal study on the response of the children to their environment, and the seventh discusses the factors that appear to have led to the opening and closing of windows. A final article by Dr. D. J. Carter describes a survey of the lighting levels in the building.

THERMAL ASPECTS O F CONSTRUCTION

The building referred to throughout these papers as the Wallasey School is referred to locally as the ‘Annexe’, as distinct from the ‘Main School’, the two portions together constituting St. George’s School Wallasey. The Main School (1955) (Figure 1) was designed as a girls’ school and the Annexe (1961) as one for boys. However, while the school was in the course of erection, the Education Committee decided to merge them into a coeducational school under one Headmaster. Apart from the use of special rooms no distinction is made between the two parts. They are closely similar in accommodation (300 pupils each) and function. They are

I06 M. G . DAVlES

F ipure I Part 01 the older part ot the school completed in I955 seen lrom the North The site is on flat land. very little above sea level and a lew hundred metres lrom the sea I t is bery windswept

architecturally dissimilar however. The only description of the building provided by the architect is his Patent S peci tica t ion.

The Annexe is a two-storied building with a corridor aligned approximately east--west running the full length of the building at ground floor level (see Figure 2). I t is in two sections. the larger housing the assembly hall. kitchens. utility rooms. toilets and five conventional classrooms at ground floor level; upstairs the library. artroom and science laboratory extend the full depth of the building (see Figure 3). The smaller section at the east end has a dinerent alignment and houses the gymnasium and service rooms.

Both sections are provided with a solar wall. That of the larger section (Figure 4) is 70.2 rn long by 8.7 rn high. I t is mainly double glazed with a separation of 62cm between the leaves (Figure 5). Above about 2cm separation the thermal resistance of double glazing varies little with separation. A spacing of 62 crn allows easy access for maintainance and accommodates the single glazed horizontally pivoted openable windows (see Figure 6 ) in either of t w o securable positions. Three walkways are built between the leaves; they provide access I'or maintenance and were seen to provide a barrier to the production of large convection currents. The panes of both the inside and outside leaves are set in an iron frame of module 1.07 rn wide by 0.61 m high. This module is used as the basis for the design of the building. Thus the ground floor occupies 4 full size modules (4 x 0.61 m)

Figure 2 Ground plan of the newer, solar heated part of the school. completed in 1961 The older part lies to the north-west of this building and is connected with it by a covered walkway The two building complexes are run as a single unit

T H E PASSIVE SOLAR HEATED SCHOOL IN WALLASEY. I 107

Figure 4. building.

Figure 3 Section through the building The first floor overhangs the ground floor on the north side

The solar wall of the larger block from the south-west. The assembly hall at the western end extends the full height of the The photograph shows the openable windows, a shuttercovered section of solar wall brickwork, some ventilator exteriors. a

small additional area of solar wall on the west elevation, and the marked slope of the roof

together with a lower inner leaf module at ground level. The upper floor occupies 8 modules of inner leaf. The outer leaf has an extra module, making 14 in all.

Each window opening occupies 4 vertical modules in the outer leaf (see Figure 7). The topmost (module 4 in Figure 7) is glazed. Modules 3 and 2 are void and face the openable window. Module 1 is also void but faces an inverted vee section of double glazing. Modules 2. 3 and 4 provide single glazing. The horizontal frame members of the outer leaf are located a little higher than the corresponding inner leaf members, presumably to accommodate this ingenious window design. Each classroom has two openable windows. (The artroom has three skylights in the roof near the north wall. These were originally single glazed and are now double glazed.)

108 M. G . DAVIES

Figure 5. View of the interior of the solar wall looking east with a section of the shuttering on the left

The east-west dimensions of the rooms can be expressed in relation to an integral number of 1.07m modules. From west to east: assembly hall 12 modules, storage wall adjacent to the stage of the assembly hall 6. utility room 3, further utility room 3, staff common room 3, staircase 2, classroom 7 (this is the classroom upon which estimates evaluated in Article I11 are based), study 4, classroom 7, staircase 2, classroom 6, classroom 6, classroom 6. Continuing with the gymnasium block: changing room area 7, gymnasium store 3. gymnasium double glazing 4, gymnasium storage wall 4, gymnasium double glazing 4, gymnasium storage wall 4, gymnasium double glazing 4.

The storage wall sections adjacent to the gymnasium are ofconcrete, 35 cm thick. The storage walls adjacent to the assembly hall and in the staircase sections are of brick (see Figure 8). The storage sections are single glazed and the outer surface of the brick or concrete lies in the plane the inner leaf elsewhere occupies. The outer surfaces of the mass wall sections (Figure 9) are covered with a form of metal and paper cladding, painted black. The areas are provided with vertical axis shutters which can be positioned so as to cover the mass wall areas, or so as to allow radiation to fall on the wall. The shutter surface which is visible when the shutter is folded against the wall is painted white to reflect sunshine and the shutters should be so positioned in summer. The other sides of the shutters are clad in aluminium. When the shutters are positioned at right angles to the wall, as they should be in winter, solar radiation falls directly onto the blackened surface of the mass wall, or is reflected from the aluminium onto the surface. The architect’s intention was originally that the panels should

THE PASSIVE SOLAR HEATED SCHOOL IN WALLASEY. I I09

Figure 6. .An openable window in the open position. The lower and a similar upper grille make the window burglar proof when secured in the open or closed position. The aluminium reflector panels are concealed behind the pinboards on either side of the window. A view to the outside is only possible through the openable window and through the lowest panel of the solar wall. The central heating radiators were installed as a precaution and are sometimes used. However, during the very severe winter of 1962-1963, the building provided satisfactory

thermal comfort using the heat of the lighting system. solar gain and body heat, without the use of these radiators

be operated thermostatically according to the outside temperature, but the 'difficulty in combining reliability of operation with low cost caused the idea to be abandoned . . .' (Clayton, 1966)

The gymnasium block (Figures 10 and 1 1 ) has a total east-west length of 33-8 m. It has two heights. At its westerly end i t accommodates a metalwork room at first floor level, beneath which is the boys'changing room. The height here is 8.7 m. The rest of the building, 23.5 m long by 5.5 m high, is the gymnasium proper (which of course occupies the full height).

The main section o f the solar wall faces about 16" west of south and the gymnasium section faces 14" east of south.

The outer leaf is of clear glass. Nearly all parts of the inner leaf visible from inside the classroom areas are of figured glass. This refracts light diffusely about the room. The object was to achieve a more uniform distribution of radiation and therefore heat over the main room surfaces.

Less than half of the solar wall is in fact visible from within a downstairs classroom (Figures 12 and 13); the remainder of the wall is obscured by large pinboards. (This undoubtedly reduces glare, which casual visitors have expected. Upstairs, the same area of pinboard constitutes a smaller fraction of the wall area though glare is not seen as a problem except perhaps in the library.) Between each pinboard and the inner leaf--ofclear glass

I10 M. G . DAVIES

Figure 7. A close up of the shutters adjacent to the staircase. The inner surfacesof the shutters are lined with aluminium to reflect radiation onto the blacked surface. The architect intended that the shutters should be actuated by remote control but this was never implemented. I t is

clear that the housing o f an openable window occupies 4 frame modules

here -is a sheet of aluminium. Five such panels are present in the larger downstairs rooms and corresponding upstairs rooms; their dimensions are 0.99 x 0.91 m2 downstairs and 0.69 x 0.91 mz upstairs. The architect intended that the bright side should be directed outward during summer to prevent part of the incident radiation from entering the room, the matt black painted reverse being exposed in winter. With its black surface outward the corresponding section of solar wall is rather less effective as a heat gatherer than is the unobscured solar wall. These devices should be reversed twice a year. Thus the solar wall consists of sections of single glazing, double glazing, double glazing with aluminium and wood layers attached, single glazed solid wall and double glazed solid wall.

The horizontal and vertical surfaces of the rooms provide the thermal storage which is necessary to restrain swings of temperature. The solid ground floor consists of lOcm screed upon 15cm of dense concrete; the intermediate floor consists of 23 cm of concrete and the roof of 18 cm of concrete. Most of the floor area is covered with thermoplastic tiles. The floor of the gymnasium is a suspended wooden floor and that of the assembly hall consists of wooden boards laid on concrete. The vertical partition walls and the north wall at first floor level are 22cm of solid brick.

The roof and vertical outside walls are clad on the outside by a 13 cm thickness of expanded polystyrene suitably protected by bitumen vapour barriers and roofing felt. This provides excellent insulation with a thermal transmittance, U. of around 0.24 W/m2K.

The east-west corridor at ground floor level is largely shaded from solar radiation and its north wall accordingly is not provided with much thermal storage. The north wall is a timber framed, timber clad wall, also containing 13 cm of expanded polystyrene; it is described in the plans as ‘ranch walling’. The north wall is broken by a toilet area, which is, surprisingly, provided with solar walling. Part of the west wall of the assembly hall is also of solar construction, perhaps to achieve a 2 per cent daylight factor. (Skylights might have been more effective.)

THE PASSIVE SOLAR HEATED SCHOOL IN WALLASEY. 1 I l l

Figure 8. A solid wall replaces the inner leaf of the solar wall to the east of the assembly hall and occupies 6 frame modules. The section is provided with shutters. The lower bank are shown positioned to reflect radiation from their white painted surfaces. The upper bank are positioned to allow radiation to fall onto the black painted surface of the brick. A walkway is positioned between the banks. and a further walkway is above the upper bank. The internal frame members of the solar wall are visible. Handrails at hand height and above the upper

walkway are to be seen

Ventilation control is provided by the openable windows (Figure 6). Except in the extreme position they lie within the width of the solar wall. The seating ensures that there is little air infiltration when the window is secured closed. Each window can be secured closed by the simple action of a handle (see Figure 14). By an unfortunate omission, the windows can only be secured in the open position by the use of a key. This is not done, windows are invariably closed by night and the cross-ventilation the architect intended in hot weather (Morgan. 1966, p. 5, line 74) is not achieved. The provision of bars below and above the windows could ensure that the windows were burglar proof both open and closed.

Ventilation through solid walls is provided by the adjustable ventilators (Figures 15-17). There have been minor troubles associated with this design. Ventilators of this kind are provided in the gymnasium, 8 on the north wall and 6 on the east wall (see Figure 18). There are no openable windows there.

The doorway into the Annexe from the Main School provides a point of uncontrolled ventilation. All outside points of access have double doors (Figure !9) which move together and have a rubber seal on the abutting edges. With their sprung return they are somewhat more cumbersome than ordinary doors would be.

Openable windows at high level are also provided between corridor and classroom (Figure 20). Although

112 M. G. DAVIES

Figure 9 One of the two sections of mass wall in the gymnasium. The wall is of concrete and occupies 4 frame modules. Its outer surface replaces the inner leaf of the solar wall

Figure 10. The boys’ gymnasium is situated at the extreme east end. The west end of this section houses a metalwork room at first floor level. behind which is a woodwork room which is provided with a clerestory section of solar wall

these could be effective by night, the staff tend to keep them shut during occupation even in hot weather, because of the noise from the corridor. There is also glazing at low level between corridor and classroom. This ensures sufficient illumination on the corridor floor; the lighting level in the corridor is otherwise rather poor.

Supplementary heat for the building is normally supplied by the lighting system. In summer lights are operated in the normal way. In winter the switches are normally left in the ‘on’ position. A time clock switches all lights on at some predetermined time in the morning and they remain on throughout the day unless they are

THE PASSIVE SOLAR HEATED SCHOOL IN WALLASEY. I 113

Figure I I View from the north-west. The photograph shows (from left to right) the gymnasium louvres, the woodwork room with some solar walling beneath, louvies for the main part of the solar building, and more solar walling serving the toilets area

Figure I 2 View of the classroom towards the southeast. The curtains were installed so that a slide projector could be used. The photograph includes six of the seven frame modules that form the east-west dimension of the room. The Seven lights (five are visible on the photo)serve asa main source of heat. A strip of hardboard adheres to the west wall. A bench/cupboard (not clearly visible) is built up to the

wall. This reduces thermal storage a little

turned offindividually. All lights are turned off again in the evening. The times are adjusted in accordance with the weather. They are turned off altogether during the Christmas holidays and may be left on 24 hours a day for a few days before term begins. The hot water radiators are sometimes used.

I14 M. G . DAVIES

Figure I 3 View 01 the artroom The pinboards occupy a fractionally much smaller area upstairs than down

Figure 14 Detail 0 1 the clasp action of the windows. Use of this clasp secures the window in the closed position and i t is easy to elTect. Means are provided. using a special key. to secure the windows in the open position. but this is tedious to do and the windows are secured closed by night The summer cross-ventilation that the architect intended should be achieved is thus not achieved, with some resulting

overheating

THE PASSIVE SOLAR HEATED SCHOOL IN WALLASEY. I 1 I5

Figure 15 View of the artroom toward the north-east. Three ventilators covered with teaching material are visible on the north wall

Figure 16. South-west corner of the assembly hall, showing the ventilators and doorway interior. The floor is of timber

1 I6 M. G . DAVIES

Figure 17. Close. up of a ventilator in the artroom

By normal heating standards, the lighting system is inadequate as a source of heat, and it has become relatively expensive since it is on the normal tariff. However, it will be noted that the heatingeffect of switching on lights is immediate and perceived everywhere in the room. The presence ofa direct source of radiation. short or longwave. is equivalent to an increase in room temperature.

T H E THERMAL BEHAVIOUR OF T H E CONSTRUCTION

The period between the completion of the building and the death of the architect may not have been suffcient tor suffcient reliable empirical evidence on the behaviour of the building to have been accumulated to provide tirm information about its actual thermal behaviour.

The Borough Architect commented in February 1966: The system has a great many advantages relating to comfort, health and planning. Heat is distributed throughout the building by radiation in the same way as light instead of by pipes, radiators, etc.

By the omission of pipes and radiators, etc., teaching rooms have more floor and wall space available for apparatus. Unlike other heating systems the air is not used as a vehicle to distribute the heat, thus the air need not be at a high temperature and ventilation is quite independent of the heating of the building. I t has been clearly established in heating research that where the temperature of walls, ceilings and floors is higher than that of the air, this gives the most ideal conditions of comfort. Also

THE PASSIVE SOLAR HEATED SCHOOL IN WALLASEY. I 1 I7

Figure 18. Gymnasium showing the ventilators in the north and east walls

temperatures of the fabric being higher than the air the body heat of the occupants is not lost into the fabric as in normal buildings.

This temperature relationship also greatly reduces the rate at which interior decorations become dirty by contact with dust in the air. and furthermore in hot summer conditions the temperature of the interior can be maintained at a level several degrees lower than that of a conventional building, the building's design properties resisting any rapid change of temperature. and this, combined with ventilation during the cool night hours maintains an average much below that of the heat of the day.

A proportion of heat is also provided by body heat of the occupants. In the winter months when the school is unoccupied during holidays and at weekends, because of the high thermal capacity of the building the temperature falls only slowly. even in severe weather. and by operating the ordinary tungsten lamps of the lighting installation on a time switch, the temperature can be raised to a satisfactory level before the school re-opens.

The scientific calculations were Mr. Morgan's and were never disclosed by him. (Clayton. 1966). Since Mr. Clayton had been concerned with the school from its inception, these remarks probably provide

the most reliable summary of the understanding of the building that was available at the time, though he had access to the report by Hitchin et al. (1966).

A more detailed description of the thermal response will be given in the third and fourth articles of this series. Attention may be drawn, however, at this stage to some useful early publications: Hitchin et al. (1966). Love (1968). Manning (1969). and Davies and Davies (1971). I t is worth quoting at length from Banham's discussion of the building (1969):

Of the example about to be discussed, it has been said that any panel of accredited environmental experts to whom it might have been submitted would have found themselves bound to dismiss i t as impracticable. The revenges of time are sweet, however, and established experts are reckoned to have spent more time and energy in trying to find out how it works than was ever lavished on i t by its original designer.

118 M. G . DAVIES

Figure 19 One of the 7 doorways into the building. Thedoorsaredoubleactingand are provided with a spring return. They are too heavy to be moved by small children. The abutments are lined with deformable rubber so as to reduce air infiltration

The building in question is the second block of St George’s County Secondary School in Wallasey (Cheshire, England). Completed in 1961. it belongs to that same generation of experimental environmental essays that were discussed in the previous chapter, but unlike them it has not enjoyed a world-wide press, doubtless because of the small fame of its designer, Emslie Morgan, principal assistant to the Borough Architect of Wallasey. Though he now has a secure reputation because the building has become something of a legend or cause celebre among British environmentalists, he died before that fame was established, leaving no documents that can now be traced to record his thoughts and methods. The double lack, of both autograph documents and of any intelligent interest on the part of architectual publications when Morgan was alive, means that the present study can derive only from inspection of the structure as it stands and as it functions . . . .

‘Structure’ is the word to emphasise, because what Emslie Morgan has offered in St George’s School is an imaginative reappraisal of one of the oldest environmental controls known to man, massive structure functioning to conserve heat, plus an attempt at improved exploitation of the oldest and ultimate source of all environmental power, the sun. The structure is almost ludicrously heavy by the standards now current in British school building-nine inch brick walls, seven-inch concrete roof all wrapped in five inches of external foamed polystyrene insulation, plus further layers of cladding for various purposes. In plan, the block is long and narrow . . . . (On the south side, the roof) pitches up to over forty feet thus providing a vast area of glass to the sun.

THE PASSIVE SOLAR HEATED SCHOOL IN WALLASEY I I I9

Figure 20. View of a classroom towards the north-west. The classroom-tocorridor windows could be opened to achieve cross-ventilation but they are normally kept closed since the corridor can be noisy. The photograph shows a sloping section to the roof, incorporated perhaps to assist daylight levels away from the solar wall. I t also shows the blackboard housing and a cupboard beneath. These reduce a

little the thermal storage provided by the double thickness brick west wall

In the designer's mind, this 'solar wall' was undoubtedly the key to the functioning of the whole building, and has also been the aspect that has caught the fancy of the public. I t consists of two skins of glass, separated by a space of 24 inches, the outer skin being clear, the inner one consisting almost entirely of obscured glass, to shed a diffused light into the teaching areas. Some of the inner skin is of clear glass . . . [Banham describes the aluminium panels].

Similarly, there are areas of the inner skin, in the assembly hall and gymnasium, that have been replaced by black-painted masonry, thermal performance being controlled by white wooden shutters that can be hung over them to reduce the absorption of solar heat.

It will be noticed that Morgan's use of glass avoids the traditional function of glazing-to be transparent to sight. There are. in fact, panes of clear glass in the hinged ventilation-windows that occur at intervals on both storeys of the facade, but they provide only scanty outward views. For this, and a tendency to overall glare from the glazed side of the rooms, the visual environment of the school has been subjected to some criticism. But about its thermal environment there seems to be no surviving doubt. now that its emergency hot-water heating system has been removed, unused, after the school had survived almost the worst winter in living memory (1962-3).

The heat so efficiently stored and managed by the massive structure has three main sources: the solar wall, the electric lighting, and the inhabitants. Of these, the solar wall may prove to be the least productive for most of the year, and the weak point in the school's armour of insulation in the cold of winter. The next most important source of heat is commonly taken to be the lights, which are switched on early to preheat the school before the pupils arrive, and some conservatively minded engineers have therefore described i t as an electrically heated building. But the greatest source of heat

120 M. G. DAVIES

is, in fact, the inhabitants themselves who, in a normally occupied class-room, provide about half the winter heat input per hour. Even if it is the total management of the heat balance which is important here, the attempt to use the waste heat from the lights at a date well before the commercial availability of systems like Barber-Coleman Daybrite (which use heat-of-light to warm input air at the point of delivery) is worth a note in any history of environment.

Nevertheless, it is the total view of the thermal environment of the complete man/structure/lighting/ ventilating system that is impressive, as well as the simplicity of the methods for its control: a time- switch for the lighting’s contribution to the diurnal heat balance, reversible panels for seasonal variations, and a card of instructions for each classroom on how the ventilation should be adjusted (by opening or closing the windows) to deal with short-term increases or drops of temperature.

One could object that this is too irregular and fortunate a case for any useful lessons to be learned from it; irregular in that it seems to work well but at variance with the designer’s intentions for how it should work (as in the case of the solar wall), and fortunate in that it seems to enjoy both a site that is admirably suited to the proposition, and a local climate marginally more helpful to its working than many others might be, even in the Same part of England. There can be no doubt that it is a special solution to a special problem, and less than perfect at that-difficulties with overheating on a few days of strong sun and no wind in high summer suggest that it needs a mild breezy climate even more than the direct incidence of sunlight for which Morgan designed it. But where is the building that does not have a few days of environmental difficulties in the year? By the going standards of environmental judgement, St George’s School has proved itself as much of a success as any other building discussed in this book, and better than most.

Its successful performance guarantees its right to be discussed here, no more; the reason for discussing it is less than it works than because it works through the application of the ultimate form of environmental, and all other, power-knowledge. Even if Morgan were to prove mistaken in details, the overall proposition that he made presupposes knowledge of the total system so complete that one can judge what to omit-the heating system was never more than a hedge against unforseeable failure to function; it was never meant to be used and never was used. The professional courage to attempt such a radical reassessment of methods of environmental management can only come when quantifiable technological knowledge, derived from experience and controlled exper- iment, has acquired the same sort of completeness and authority as the accumulated rules of thumb by which vernacular cultures manage their environments.

REFERENCES

Banham, Reyner. (1969). The Architecture 01 the Well-tempered Environment, The Architectural Press, London. Billington, N. S. (1947). ‘Solar heat gain through windows’, J . Royal Institute of British Architects, 54, 177-180. Clayton, W. P. (1966). ‘Notes on the new St. George’s Secondary School, Leasowe. (Solar energy)’, County Borough of Wallasey-an

Davies A. D. M. and Davies, M. G. (1971). ‘User reaction to the thermal environment-the attitudes of teachers and children to St.

Davies, M. G. (1976). ‘The contribution of solar gain to space heating’, Solar Energy, 18, 361-367. Hammond, G. W. and Trubshaw, G. E. (1968). ‘The Morgan principles for solar heated buildings’, unpublished article presented at the

Hitchin, E. R. , Thompson, K. and Wilson, C. B. (1966). ‘The thermal design and performance of St. George’s County Secondary

Love, J. (1968). ‘Economic comparison of the solar and conventionally ’heated sections of St. George’s !kondary Modern School,

Manning, Peter. (1969). ‘St. George’s School, Wallasey: an evaluation of a solar heated building’, Architects Journul Injormation Library,

Morgan, E. A. (1966). ‘Improvements in solar heated buildings’, U.K. Patent Specijication 102241 1, application date 6 April 1961,

internal note, dated 8 February 1966.

George’s School, Wallasey’, Building Science, 6, 69-75.

Thermal Insulation Conference, Cardiff, December 1968.

School, Wallasey’, J. Inst . Hear. Vent. Engrs., 33, 325-331.

Wallasey’. T.R.G. Report 1636, H. M. Stationery Office.

25 June, 1715-1721.

complete specification published 16 March 1966, The Patent Office, London.