1.0 Introduction
1.1 Background
Traditional dry sports hall design has tended
towards an approach which excludes daylight from a space. This is an
inevitable consequence of technical and professional guidance which has
largely focused on the problems associated with daylight including
glare, overheating, local cooling, unmanageable variation in light
quality and quantity and unwelcome distractions.
The resulting designs are incompatible with
attractive architecture and pleasing indoor environments. It is also
evident that this “black box” approach has become
incompatible with the resource conservation, pollution prevention and
cost-in-use savings which attention to energy efficiency can provide.
Lighting strategies are a significant aspect of delivering energy
efficiency and the situation in sports halls is exacerbated by the
constraints that this approach to design places on other servicing
strategies, in particular ventilation.
sportscotland is keen to encourage participation in
sporting activity by people of all ages. In pursuit of this objective
they are aware of the need to promote buildings with low running costs,
thereby enabling cost of participation to be maintained at an
affordable level. They are particularly keen to attract small
children and their carers, people with disabilities, ethnic minorities
and the elderly, all of whom can benefit from enhanced fitness and
social interaction. Improving daytime indoor environments is seen as a
significant aspect of improving utilisation by these groups. Daylight
is perceived as offering particularly attractive opportunities which
for reasons mentioned above has been significantly under utilised.
sportscotland is also aware that in recent years an
increasing number of sports halls have been built where daylight is
used. Only the earliest examples are documented.3 All are in
largely unchartered territory. Hence this study has been commissioned
which will gather additional information on the most contemporary
designs, their perceived successes and failures, designers needs and
failings of present guidance.
The result will be up-to-date, concise guidance on
the beneficial, integrated use of daylighting in sports halls,
presented in an appropriate format for designers, clients and quantity
surveyors. It will address architectural, engineering and cost issues
side-by-side and be comprehensible to all disciplines. It is not
intended to be a technical digest with prescribed do’s and
don’ts but rather to encourage an improved understanding of
daylighting design principles, and provide assistance in communication
between the disciplines which can, if appropriate, follow through into
successful design.
1.2 Primary Objectives
The report to be published on completion of this
research in August 2001 should assist the reader to:
• Understand
the benefits of utilising natural lighting in sports halls;
• Appreciate
that daylighting can contribute significantly to the energy efficiency
of a sports hall;
• Appreciate
that daylighting can contribute significantly to the architectural
opportunities of a sports hall;4
• Communicate
to clients the importance of daylighting to running costs savings;
• Appreciate
good practice in natural lighting design in general and in sports halls
in particular, and its integration with artificial lighting and other
building services;
• Understand
the requirements and constraints of individual activities and standards
of play, in relation to patterns of use, lighting levels, variations in
light quantity, subjective responses and spatial needs;
• Understand
and be able to access the guidance, tools and techniques available for
daylighting design;
• Be capable
of making informed decisions to assist in designing a sports hall that
uses daylighting without detriment to the activities;
• Understand
the requirements and constraints of different design and control
strategies, in relation to building operation and maintenance;
• Work
creatively with others disciplines [architect, engineer, qs, client and
building managers] in the design process.
1.3 Summary Conclusions
The documented examples appear to have varying
degrees of success. It is evident that for the aesthetic and amenity
reasons mentioned above, daylighting is to be encouraged. The energy
benefits are also indisputable if well designed. However, extreme care
and attention to detail is necessary if any of the benefits are to be
realised in practice. Principal problems are the adverse impact on play
and the lack of exploitation of energy efficiency opportunities. The
problems which have been identified could inform future design.
Of those designers interviewed in connection with
recent buildings most felt that these had been reasonably successful.
Building users, including staff, were more circumspect. Many users
evidently realised and valued the quality aspects of the daylight but
were frustrated by the adverse impact on play - even at a very casual
level of participation. Some, in collaboration with management, changed
their activity schedules and/or locations in order to minimise the
adverse impacts. Staff experiencing glare problems tended to create
permanant solutions; rooflights covered by play mats and curtains down,
lights on being notable examples from field studies.
Managers rarely knew what light controls were
available or how to use them properly. Hence lights tended to be turned
on at the start of day and off at the end, regardless of daylight
level, occupancy or activity. This is despite of the fact that in most
cases the lighting had a number of modes which could have been used to
generate energy efficiencies. Automatic controls have not been observed
in operation and so no assessment can yet be made of their efficacy or
of user attitudes to them.
Problems were normally identifiable to certain
times of day and/or year as a consequence of south-facing and
west-facing glazing; indicating that attention to detail could assist
in problem avoidance and that retrofit action was also an option. The
latter gives rise to a “suck it and see” design approach,
and attitudes to this vary. It may be that this is indeed the
appropriate way forward in design terms, but it relies on a significant
shift in attitude to the design and procurement process. Much of the
relevant discussion is highlighted in recent work by Bordass5 as a
consequence of the well documented Probe Studies. Simply put, the
expectation that buildings work optimally and according to design
aspirations from the point of handover is unrealistic and leads to risk
aversion. It is a significant contributor to oversizing, and missed
opportunity and unhelpful to the pursuit of best practice. The
alternative has rarely if ever been tried and documented and relies on
a range of circumstances and designer - client relationships which are
largely absent from existing procurement practice.
One issue that is becoming evident is that
clerestory daylighting, which dominates the design approach in
Scotland, can create glare problems. Halls that use rooflights suffer
from fewer complaints. In two of the centres the daylight aspect
(clerestory) was inadequate to make a significant contribution to
activities for most of the time and, at one, it was a significant
generator of problems simultaneously. Dark ceilings were observed to
accentuate problems of insufficient daylighting. Roof lighting was more
successful. A combination of clerestory and rooflighting seems to
reduce glare complaints.
Site surveys also identified the kinds of problems
found in many buildings. For instance, openable windows which should
assist summer ventilation were out of reach; probably a result of cost
cutting. Electricity, other than for lighting in sports halls, was also
squandered in cafes, locker halls, pools where daylighting was adequate
and in unoccupied toilets, due to poor control and/or lack of
management intervention.
It is apparent that professional and technical
guidance is not helpful to strategies for energy efficiency and quality
in architecture; too rigorous and often contradictory. Practitioners
need:-
up to date guidance;
more information on success and failure of examples
built;
more support for flexible approaches;
cost in use information.
In respect of present guidance, CIBSE and
simulation programmes were thought to be poor and a need for more
information on glare and colour matching was identified. A significant
restraint on contemporary practice was identified as the difficulty in
convincing clients/funders of the value of daylighting.
