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<B><FONT SIZE=鈥�+2鈥�>Introduction</FONT></B>Large-scale, purpose-built indoor arenas have been developed in a number of cities in the UK during the 1990s, providing flexible accommodation for a wide range of indoor spectator sports and events. Arenas are complex buildings, for which operational issues need to be considered carefully at the design stage. In this month鈥檚 cost model, Davis Langdon & Everest鈥檚 arena and stadium specialists examine the costs and specification of a multipurpose arena.
One of the most significant reasons for the construction of purpose-built indoor arenas has been the growing popularity of indoor spectator sports such as ice hockey and basketball. Arena projects, typically developed in the centre of large cities such as Sheffield, Manchester and now Belfast, have also become an important component of many urban regeneration programmes, bringing private investment and people back into previously derelict inner-city areas.
When centrally located alongside good transport links, arena developments can act as a catalyst for regeneration, regularly drawing large audiences to otherwise neglected areas. The flexible space provided by a well-designed arena can support a wide range of sports, concerts, exhibitions and other events.
Arenas must be managed effectively, as their capital value is derived from the quality and efficiency of management rather than from the value of the building itself. Accordingly, the following issues are fundamental to the successful design and delivery of an arena development:

 

 

• Balancing the comfort conditions with the overall capacity of the arena

 

• Maximising the efficiency of building operation through appropriate investment in mechanisation of equipment

 

• Optimising the design of the arena for sports and customer requirements, within the constraints of the budget and programme.

In order to be viable, arenas must house home teams for at least two sports, usually ice hockey and basketball, ensuring year-round regular ticket and broadcasting income.

<B><FONT SIZE=鈥�+2鈥�>Operational issues</FONT></B><B>Sources of income</B>
Ticket sales are the prime income source of an arena; rent from events promoters provides more than 60% of revenue.
It is difficult for operators to achieve full utilisation of an arena seven days a week because, in the UK, there is a limited number of spectator sports that could fill an arena. It is also rare for events, other than concerts, to sell out. An arena business plan must be based on a cautious assessment of potential revenues and, as a result, it can be difficult to attract initial commercial investment without public sector funding.
In addition to ticket sales, most sources of revenue, for example, merchandise and refreshments sales, are related to the size of the audience. Only a small proportion of income, typically related to box and season ticket sales, is fixed.
In common with other leisure destinations, arena operators are seeking to increase non-ticket-based incomes by enhancing the capacity and quality of retail and catering concessions and other facilities, increasing the amount of time and money customers spend there.
<B>Operating costs</B>
The table summarises operating costs for a typical arena. Event costs include all the costs of casual staff and equipment hired by the operator. More than 40% of total costs are related to staff. Staff costs can potentially be reduced by higher levels of initial investment in the mechanisation of installations in the arena, such as moveable seating or the insulated floor and perimeter barriers of an ice rink. Increased mechanisation also helps to reduce the down-time involved in changing the configuration of an arena and can result in increased revenues.
Maintenance and utility costs are about 14% of running costs, reflecting the resources required to keep a highly serviced building operating efficiently.
<B>Back-of-house facilities</B>
Back-of-house facilities in arenas include television and press facilities, function rooms and VIP areas, as well as changing areas, and catering and administration facilities. The design of back-of-house space can have a significant effect on the quality of operation in the arena. Early input from the operator on the range, size and location of back-of-house facilities is valuable, but can be difficult to obtain, as operators are often not signed up until late in the design programme.

<B><FONT SIZE=鈥�+2鈥�>Cost drivers</FONT></B>Typically, the range of capital costs for arena developments can be broad, as there are many variables that influence arena size, configuration and capital cost. The following cost drivers have a significant impact on the design and costs, and need to be considered in detail at an early stage to ensure that an arena proposal is feasible from both operational and economic perspectives.

<B><FONT SIZE=鈥�+2鈥�>Arena capacity</FONT></B>Arena capacity is the principal cost driver, as the number of seats determines the size of the arena bowl, the extent of circulation and other facilities. Arenas with a capacity of 9000-13 000 are common in the UK. The cost of the seats alone can amount to 5-10% of the capital cost of an arena development.
Capacity is not the only determinant of overall cost, but it has a major influence on other factors such as tier configuration, footprint and clear roof span. Actual capacity differs from one event to another, according to the size of the event floor and how much retractable seating is in use. Capacity can vary by +/鈥�3000 seats in a 7000-seat arena.
<B><FONT SIZE=鈥�+2鈥�>Tier arrangement</FONT></B>The number of tiers required is determined by capacity and means of escape regulations. The table on bowl capacity sets out typical arrangements related to arena capacity.
Overlapping and multiple seating tiers generate the following benefits:

 

 

• Reduced development footprint and roof spans

 

• Sufficient space for concourses, concessions and ancillary accommodation within the bowl structure

 

• Relatively short viewing distances

 

• Reduced spectator travel distances to concessions and other facilities

 

• More direct escape routes.

Although single-tier arenas cost less per square metre to construct than multiple-tier arenas, extra space is usually required at the perimeter of a single-tier bowl to accommodate concessions and other facilities.
<B>Size of the main event floor</B>
The size of the main event floor determines the capacity and design of the arena bowl. In general, the larger the main event floor, the larger and more costly the building, as footprint and roof spans and the requirement for mobile seating increase. Most operators require 60 脳 30 m as standard; large enough to accommodate ice hockey, but only 36% of the surface area needed for the largest main event floor, for indoor athletics, that measures 100 脳 50 m.
Seating space allowance influences the quality of a visitor鈥檚 experience of the arena. Standards should be as high as possible within the constraints of the budget. Space standards affect the size of the arena bowl, footprint, the clear span of the roof and the cost of the seat itself. A typical space allowance on the tier is 0.5 m² per seat, including access.
<B>Clear roof span</B>
Roof span is a significant cost driver. Once beyond a clear span of 60 m, each additional metre results in a disproportionate increase in the weight and cost of the roof.
<B>Bowl layout and provision for expansion</B>
Most arenas are U-shaped, with one end left open, providing space for an end stage for concert events. Concerts generally attract the largest audiences and it is therefore not economic to provide fixed seating across the free end of the bowl for other sporting events.</B>
<B>Flexibility of seating arrangements</B>
The requirement for flexible seating is driven by the combination of events for which the arena is designed. If the main event floor is designed for athletics, then up to 50% of bowl seating will have to be moveable or retractable to adjust to court sizes required by other sports. Moveable seating costs, on average, 拢300 per seat, 250% more than fixed seating. Flexible seating also reduces the amount of storage space available below the bowl. The loss of this space, together with the need for storage space for retractable seating, may result in a requirement either for a larger bowl footprint or extra space outside the bowl.
Boxes, restaurants and other premium club facilities are an important generator of revenue, and can be readily incorporated as an intermediate level into a two-tier bowl.

<B><FONT SIZE=鈥�+2鈥�>Design issues</FONT></B><B>Requirements for sporting events</B>
The selection of the main sporting event has considerable influence on the size and layout of the arena and also has cost implications.
Ice hockey requires the largest single dedicated investment, the ice floor. The total cost of an ice floor installation, measuring 60 脳 30 m, including power, refrigeration and other consequential modifications to building structure and services, is approximately 拢1.5m. In addition to the construction of the insulated ice pad, there are ducts, the ice pit and storage space for dedicated equipment, such as the insulated floor, the barrier system and ice machine.
Basketball requires a floor size of 30 脳 18 m.
A combination of retractable seating and conventional seating on risers is required to change the configuration of the arena to suit basketball.
Indoor athletics tracks require large event floors, dictating the need for extensive retractable seating. In most cases, the tiers will be raked to suit other events, such as ice hockey, and as a result the track may not be fully visible from all seats.
A retractable track and in-field will cost 拢550 000; plus another 拢50 000-100 000 for builders鈥� work.
Storage requirements for seating and track are extensive and may result in a further requirement for ancillary accommodation beyond the perimeter of the bowl.
<B>Roof</B>
The key design issues related to roof structure concern the economics of large clear spans and the design for progressive collapse of the roof required in a public assembly building.
The structural alternatives available to designers are space frames and trusses. As well as being relatively inexpensive, such structural forms have a depth that is useful in accommodating mechanical services, ducts and walkways.
The weight of a space frame is typically 75% that of an equivalent truss. The use of a space frame can generate additional savings, related to frame and foundation design, that offset the higher cost. However, the small market for space frames leads to procurement risks at an early stage, and most designs adopt a trussed solution.
Clear spans of more than 60 m incur significant cost penalties related to the tonnage of steel required and the complexity of fabrication and erection. The average tonnage of a 60 m clear-span roof is 85-90 kg/m², increasing to an average of 100-110 kg/m² for a roof spanning 100 m.
Arena roof structures are designed as working platforms providing a loadbearing element for scoreboards and concert staging. Central scoreboards weigh at least 10 tonnes, and a total suspended load allowance of 40 tonnes should be provided above stage areas.
<B>External envelope</B>
The sheer size of arena buildings makes the design of the external envelope a difficult task. Massing is a key design issue, and the quantity of envelope means that the total building cost is very sensitive to relatively minor changes in specification. A variety of external walling treatments, masonry or insulated panels, for example, can be used to provide levels of performance, durability and appearance appropriate to various locations on the external wall.
Architectural masonry and other hard materials are often specified at concourse level to provide a high-quality, durable finish, whereas more economic materials can be used to clad the roof, which is usually out of sight.
Arenas are usually designed as 鈥渂lack boxes鈥�, and the extent of fenestration is limited in order to control light levels and glare in concourses, providing, where necessary, an uninterrupted back wall in concession units.
Most arena roofs are curved on plan and section, following the form of the bowl. Lightweight raised-seam aluminium roofing is the most suitable material for cost-effective roofing.
<B>黑洞社区 services</B>
The key areas that need to be addressed in the design of the building services installation are listed in the table above, which summarises typical environmental criteria for arenas.
Environmental conditions in the arena space are maintained by using a low-velocity air-conditioning system with the in-built flexibility to adjust to different densities of occupation and uses.
Cooled air is supplied only to spectator areas, and when the arena is in use for sporting events, the event floor is isolated. A wide range of internal conditions are acceptable to the audience, and close control is not required.
Air-conditioning in other areas will be serviced by various dedicated systems designed to suit patterns of occupancy.
The nature of the sport determines the quality, levels, direction, colour and brightness of lighting required, which should all be adjustable.
Lighting standards are set out in the Guide to Artificial Lighting of Multipurpose Indoor Sports Venues published by the General Association of International Sports Federations and the European Broadcasting Union. According to the type and level of sport, the lux level required will range from 150 to 2000 lux.
Dedicated mechanical smoke extract is required within the arena and concourse areas. Sprinkler installations should be provided in storage areas, concessions and escape routes, and other areas can be serviced by hose reels.
Fire detection is typically by a fully addressable type L1 system with a zoned public address. An arena voice-over evacuation system complying with BS5839: Part 8 and BS6250 should be specified to include interfaces to all concession areas.

<B><FONT SIZE=鈥�+2鈥�>Project management and procurement</FONT></B>The key issues associated with the project management of an arena development involve the co-ordination of a multi-party client body, consultation with third parties, and the management of the approvals process for a public building. The client body for an arena project will usually consist of both private sector and local authority development partners. An operator will also be involved at a later stage, but it is important that operational efficiency, the establishment of economic running costs and the maximisation of the facilities within the arena are considered from the outset.
The principal activity of the project manager at the early stage of a project will be related to the business plan. This will involve the input of marketing and events consultants. The planning stage is vital, as the anchor sports events identified in the business plan should determine the capacity and design of the arena. The governing bodies of major sports events, together with organisations, broadcasters and other third parties will also need to be consulted as part of the design process.
As the design develops, a strategy for obtaining fire and entertainments licences will need to be put in place.
Invariably, the business plan will show that cost is the main constraint affecting the development of an arena, so capital budgets are usually kept low. Even so, investment in robust construction is very important, as arenas have to stand a great deal of wear and tear. Other factors affecting schemes include the need for programme completion to coincide with the season of the anchor sport.
The procurement of an arena development typically follows a develop-and-construct route, with a high degree of design development taking place before the appointment of the contractor and the novation of the design team.
Following a two-stage process, a contractor will be appointed at scheme design stage, on the basis of priced preliminaries and rates for major items of work. The contract sum will not usually be fixed until the completion of detailed design, at which point most subcontractors will have been appointed by the contractor, with the approval of the design team.
Furniture, fittings and equipment installations are usually funded through a developer鈥檚 contribution to the operator鈥檚 fit-out and will often be installed as part of the main contract. It is good practice for the employer to clearly identify the scope of the FF&E installation in the main contract documentation to ensure that the scope of the work is understood, and that attendances for any direct contract works are included.

<B><FONT SIZE=鈥�+2鈥�>Cost breakdown</FONT></B>The cost breakdown is for a notional 7100-seat arena with a gross floor area of 22 500 m². The arena features an ice-rink and a fully demountable athletics track. Half of the tiered seating is retractable. The costs of the ice-rink and track installations are included in the breakdown, but furniture, fittings and equipment costs are excluded. The total FF&E budget for an arena of this size would typically be 拢2m-2.5m (拢90-110/m² gfa).
Costs are current in September 1999, based on a location in south-east England. The level of pricing assumes procurement on the basis of a two-stage tender, following the develop-and-construct route. Adjustment should be made to the costs detailed in the model to account for variations in phasing, specification, site conditions, procurement route, programme and market conditions.