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‘At a time when the Government, the house building industry, economists, homebuyers and renters are concerned about whether we are building enough new homes in the UK, it might seem odd to suggest that the focus should move to thinking about the quality of those homes. And yet this is the very time to do so. In a rush to build quickly and cheaply we risk storing up unnecessary problems for the future. We do not believe that there is any need to see a contradiction between building or refurbishing enough homes and making sure that they are of the highest quality’.

- Harry Rich, Chief Executive, RIBA (2011, RIBA: The case for space, p.3).

This chapter considers the historical development of UK housing in the 1980s and the 1990s with a focus on design, materials, construction methods and environmental sustainability. The arrangement of internal spaces of housing during the period with the consideration of internal floor areas, floor-to-ceiling height, internal conditions and internal partitions will be mentioned.

The minimum space standards used at different times before the 1960s (the decade that saw a great development in UK minimum space standards with the introduction of the Parker Morris standards) till the current time (that is, the whole period under consideration) will be examined. The importance of the Parker Morris minimum space standards as a point of reference over decades and their abolition in the 1980s will be briefly discussed. Other minimum space standards such as the English Partnerships space

standards, the Greater London Authority’s (GLA) space standards, the Developer

standards used for housing developments will be highlighted. Comparison of the various minimum space standards will be provided. The UK minimum space standards will be compared with minimum space standards in other European nations to provide a better

understanding of the UK’s position and the progress made so far in terms of

30 At the later part of this chapter, prefabricated timber housing development in relation to sustainability in terms of materials will be discussed. The current developments and future prospects in the UK and the world will be presented. Also, the comparison between developments in various leading countries in timber housing stock will be mentioned.

3.2 Review of UK Housing in the 1980s and the 1990s

The late 1980s to the 1990s saw a great development in the use of timber-framed construction for houses. The late 1980s also saw the development of prefabricated timber-

framed houses across the UK after rejection of timber-framed construction in the 1970s.3

Prefabricated timber construction methods were once considered for houses in the UK. Attention was on improvement of cavity wall insulation (50-100mm width) and performance of timber houses during the 1990s with a focus on energy conservation. Also, problems relating to leakage through windows, dampness and use of plasterboards for internal spaces were widely considered. Planning of internal spaces with smaller sizes for energy conservation, reduced size of windows, reduced floor-to-ceiling heights were noticed in modern houses built with timber. Heating was provided in all habitable spaces and the rooms were expected to be naturally ventilated in summer. The gable roofs of the houses were covered with tiles. Most of the houses built were clad with bricks to make the houses look like other conventional houses and different housing typologies were developed. Since majority of the houses built during the period were privately financed houses, they were built to Developer standards. Also in the 1990s, the Conservative government came up with the plan to build an additional 4 million dwellings by 2020 with the use of modern methods of construction. This was done to improve housing conditions but the overall well-being of occupants was not adequately taken into consideration and this study will examine summertime high temperature in modern timber houses in the UK to understand if occupants are comfortable within internal spaces. The houses developed during the period suggest a shift to timber-frame construction which was not accompanied by consideration on the overall environmental effects of internal space, especially volume, orientation etc.

3

The prefabricated timber-framed houses produced during the period can be assembled on site with a limited number of site workers when compared to traditional timber-framed houses as all the components (walls, floors, roofs) have been processed to the required sizes from the factory.

31 The late 1990s saw a move from construction of prefabricated timber-framed houses in the UK to construction of houses built with prefabricated structural timber panels such as cross-laminated timber (CLT) panels and structural insulated panels (SIP).4 Structural timber panels provide internal load-bearing support at every part of the timber panels than timber-framed panels. Structural timber panels also provide vertical, horizontal and angular load-bearing support to different houses. The shapes of many timber panels’ houses are rectilinear especially in blocks of apartments. In some cases, the floor plans alternated to provide articulated facades. The internal spaces are not deep with considerable size of openings. The arrangements of spaces were done in open plan

designs with limited provision for partitions which reduces occupants’ privacy. The floor-

to-ceiling height was between 2.1-2.4m depending on the minimum space standards used for construction. The materials used for cladding varied from bricks, timber, and concrete. In some cases a combination of two or more materials was used for construction but conventional cladding materials were preferred over non-traditional materials. Also, the building materials were locally sourced while timber panels were brought to the UK in some cases due to increase in demand for timber panels which suggests additional energy used for production and transport to site. The materials were mass produced in the factory with tendency for necessary adjustments on site and low potential for materials wastage. Structural timber panels have been increasingly used for construction of UK houses since the late 1990s to the present time and various houses built with prefabricated timber panels in the last decade will be presented in Chapter 5.