Design Review: Volume 1, Issue 6 (April-May, 1949)
Prefabricated Houses in Aluminium
Prefabricated Houses in Aluminium
An exhibition of factory-built aluminium alloy bungslows was staged recently on a site near the Wellington Railway Station by A. W. Hawksley Limited, of Hucclecote, Gloucester. These houses attracted considerable public attention and the desirability of their use in New Zealand to speed up housing construction was widely discussed by laymen and architects.
The question of prefabrication is still a very controversial issue in most countries. The main questions raised usually are:—
Cost in comparison to tradition-built houses of same floor area.
Weathertight construction and insulation from cold and sound.
Flexibility in the arrangement of the prefabricated units of which the building is composed, so as to permit variety in size, plan and appearance.
How do the Hawksley factory-built homes meet these requirements? It is necessary to face up to these questions seriously in the interest not only of the general public but also of the producer. Any serious shortcomings would very soon wreck the market for that product and moreover, might introduce a long-lasting bias against any factory made houses. In the opinion of the reviewer, this would be a very regrettable reaction.
There is a field for factory made houses, especialy where use is made of materials such as aluminium relieving the shortage of timber and cement which are bulk items in N.Z. tradition-built houses.
The External Walls consist of aluminium framed and braced panels faced externally with formed aluminium sheets and lined with hardboard. Insulation is provided by a panel inter-fill of fibre-glass blankets.
The Internal Walls consist of aluminium framed and braced panels faced on both sides with hardboard.
Doors and Windows: Timber doors and fully glazed aluminium framed sash windows are supplied integral with the wall panels.
Roof: Aluminium roof trusses and purlins are supplied in subassembly form together with roof sheeting panels of formed aluminium sheet lines on the underside with insulation board. Ceilings consist of hardboard panels.
All aluminium structure and sheeting (except roof sheeting) is degreased dip-painted and stoved prior to fabrication. Roof sheeting is not painted so that the full reflective properties of bright aluminium are used for heat insulation.
The insulation value of the walls is stated to be equal to that of an 11in. cavity brick wall. Sound-transmission figures are not available but are considered normal.
The houses may be erected (as in England) on to a concrete slab foundation which is subsequently floored with bitmnastic coloured tiles or on to traditional types of foundation such as brick, concrete or timber piles with timber flooring.
The structure is borer and termite-proof and has a very low fire and earthquake hazard.
The cost of the completed unit ready for occupation and including the necessary sanitary and kitchen equipment (a refrigerator figures prominently in the women-folks' attention) is given as below £2,000 for the 920 sq. ft. house, at destinations within 10 miles of the major ports. This would amount to aprox. £2 a sq. foot. The stoved and All-clad aluminium components ensure almost complete protection from corrosion and maintenance, costs should be lower than for a timber house.
The quality of the equipment provided is of well-known high English standard. Particularly interesting features are the provision of a refrigerator, an electric wash-boiler and a water-heating unit incorporated in a fireplace which may relieve the electric clement in winter time.
Unfortunately, however, it seems that the English manufacturer has not been advised of the very high and now almost universally accepted requirements and standards in New Zealand. In consequence there is a lack of bench length and storage space in the kitchen. Almost all laundering is done at home in New Zealand, so that a laundry or utility room is essential unless a washing machine can be supplied. Such utility room could, of course, be added by the manufacturer but must increase the price. Wardrobe and general cupboard space is also small.
Flexibility of Design
The wall panels are interchangeable so that the position of windows and doors may be varied to suit individual requirements. However the very large size of the panels will have the tendency of rendering the planning of differing types of houses more difficult than with the usual panel of a width of 3–4 ft. For instance, the panels cannot be so grouped that a continuous row of window units or French doors could be arranged. However, the Hawksley company overseas has turned out smaller panel sizes and many other types of houses.
General Planning and Design
In the sphere of design these particular bungalows do not do full justice to a generally sound and promising method of prefabrication. The plan which was presumably designed for different conditions of living would not orientate well to the sun and the garden.
The windows are badly proportioned and factory-like is appearance with unnecessary bars dissecting the view. Large side-hung casement windows are, however, available as alternative. In general, plan and elevations of the exhibited bungalow are unimaginative, and whilst it is obvious that the design aims to meet she taste of the quoted man in the street, certain changes would have to be made before it suited the average New Zealand housewife.
However, the firm has produced incomparably better designs as instanced by the two-storeyed house with good ample windows shown below. Nevertheless, the only really satisfactory solution would emerge from the employment of a modern New Zealand architect versed in our conditions, standards and requirements.