The impact of design evaluation on apartment quality

The importance and value of internal design quality in high density apartments has gained wide recognition globally. As many cities grapple with the complex issues presented by rising population numbers, increasing urban residential density is considered an important housing solution. In many cities, the apartment construction boom has coincided with increasing pressure on housing in terms of affordability and rising levels of property investment. As a result of these competing pressures, many design practitioners, policy makers and the general public have expressed concern about the quality of living that current apartment design allows.

The role of design assessment

The value of government intervention into design quality in apartments through Design Assessment Tools has also been highly debated, with questions raised over the opportunities and limitations of different methods of measurement to promote good apartment design quality.

Quantitative methods are argued to produce a clear and precise definition of design quality which leads to certainty in assessment [1]. It is important, however, that the quantitative methods of measurement used in Design Assessment Tools are sophisticated enough to also capture the more qualitative elements of design. Qualitative elements are subjective and therefore unable to be specifically measured quantitatively but contribute important aspects to the living quality of the apartment [2][3]. This research therefore investigates whether the method of measurement in Design Assessment Tools affects the tool’s ability to facilitate the delivery of design quality.

Testing two different approaches to assessment

This research tests two quantitative tools; Melbourne’s Better Apartment Design Standards (BADS) and London’s Housing Supplementary Guide (London Guide) against a series of apartment building plans in Melbourne and London. It evaluates the functions and limitations of two different measurement approaches in the tools to improve the quality of design outcomes.

Extracted from a larger Australian Research Council (ARC) funded PhD research project, this article outlines in brief the findings when reviewing the approach to design assessment of ‘Functional space’.

Functional space is a spatial element in both the BADS and the London Guide that is included for design assessment (see Figure 1). The London Guide measured total apartment size while the BADS tool measured the individual rooms within an apartment. The BADS approach consequently limited what could be measured and placed greater emphasis on the elements that were being measured.

The approach used for the Better Apartment Standards

The minimum room size measurement set by BADS made for a clear and simple delineation of acceptable quality, rejecting living rooms which were too small to fit the basic ‘required’ furniture in functional arrangements for living rooms .The minimum width and depth for the bedroom also removed irregular shaped rooms, for example, triangular shaped bedrooms which resulted in unusable spaces in the point of the triangle and insufficient space for a person to access both sides of the bed (Figure 2).

The specific nature of the different components measured by the BADS ‘Functional Layout’ standard was shown to assist the clarity and certainty of the design quality detected by the tool. However, the separation of elements means that all elements need to be listed if they are to be considered. In focusing on detecting sufficient room size only, BADS ‘Functional Layout’ misses other elements like door or circulation placement in the overall apartment layout. These elements contribute to the qualitative design quality of apartments that relate to the arrangement of spaces and the relationships between spaces [4].

This is demonstrated in Figure 3 which shows two apartments that both have living rooms that comply with the BADS room widths. While the living room on the left is situated off the thoroughfare, the layout of the right apartment means that the living room is a thoroughfare that is used to access the balcony and bedrooms which reduces the amount of usable space in the living room.

The approach used for the London Housing Supplementary Guide

The London Guide ‘Dwelling Space Standard’ is also a quantitative tool but differs markedly from BADS in that it allows a combination of elements to contribute to compliance. This enables the tool to incorporate both quantitative and qualitative elements of design quality. The total size for the London Guide ‘Dwelling Space Standard’ is the total quantum of space that would be required to deliver a functional apartment. The total size is determined based on a comprehensive list of rooms that each sufficiently fit 'required' furniture in a typical arrangement.

The London Guide ‘Dwelling Space Standard’ is also a quantitative tool but differs markedly from BADS in that it allows a combination of elements to contribute to compliance. This enables the tool to incorporate both quantitative and qualitative elements of design quality. The total size for the London Guide ‘Dwelling Space Standard’ is compiled from a comprehensive list of rooms and the quantity of space that would sufficiently fit all furniture within each room in a typical arrangement. The important point of difference between the BADs and the London Guide was that the London Guide not only includes all rooms in the measurement, but also space for circulation and layout of the rooms in a useful configuration as a whole apartment. This results in apartments that are not simply arranged to meet minimum size requirements (a quantitative design element) but instead support the design of apartments that are well arranged and functional (qualitative design elements).

Comparing different design outcomes

The difference of approaches to assessment can be seen in the comparison of one-bedroom apartments in Melbourne and London. A one-bedroom apartment from Melbourne was able to comply with the room’s dimensions set out in the BADS but did not meet the London Guide ‘Dwelling Space Standard.’

This apartment had prioritised providing sufficient space in the rooms identified in BADS (the living room and bedroom) but did not include sufficient space to support the functional arrangement of rooms within the apartment. In this case, the bedroom and bathroom door opened directly onto the kitchen corridor and the main entrance to the apartment. This meant that this space was a high traffic area which resulted in little privacy for anyone using the bedroom or the bathroom (Figure 4).

In the London one-bedroom apartment, which also complies with the London Guide 'Dwelling Space standard', the entries for the bedrooms are completely separated from the living space. An additional circulation space of 4.5-5.5m2 for 1-bedroom apartments and 9-10m2 for 2-bedroom apartments is also provided between the two areas (Figure 5).

Together this layout provides a buffer between the social areas of the apartment and the more intimate areas of the bedroom and avoids any instances of lines of sight between the two. It also enables the bedroom to be discretely linked to the bathroom so that a person may use this area of the apartment without having to enter the social areas of the apartment.

While it is possible to arrange the apartment more effectively while complying with the BADS, it is more difficult to achieve a good design outcome without integrating sufficient space for circulation. Using a total apartment size metric to assess apartment design allows for a broader and more holistic review of design quality than design assessment tools that prescribe metrics relating to individual elements within an apartment.

How Design Assessment Tools are written matters

These findings have illustrated that not all methods of quantitative measurement are the same when it comes to facilitating the delivery of design quality. A narrow or separated approach to design assessment, as seen in the BADS ‘minimum rooms size,’ result in unintended impacts on design quality by overemphasising the design of certain elements over others.

While specifying living and bedroom sizes provides certainty and clarity for these two aspects of apartment design, it also focused attention only on these two elements of design quality, and thus removed or excluded attention from other important qualities, like the arrangement of rooms which was outside of the scope of measurement.

While a quantitative tool like the London Guide ‘Dwelling Space Standard’ does not measure qualitative elements, importantly it does operate on the holistic apartment level which gives it the flexibility to be able to incorporate qualitative elements (such as the arrangement of rooms), albeit indirectly.

The London Guide tool reveals more about overall quality than the BADS simply because of the way the two tools are configured. Therefore, amongst quantitative assessment tools, it matters exactly how the quantification/assessment is set up and undertaken.