Sustainable Working Place concept/ model, case Aleksis Kiven katu 9

Transcription

1 Sustainable Working Place concept/ model, case Aleksis Kiven katu 9 Juha Olkinuora MSc (tech) 1 Reijo Kaurela MSc (tech) 2 1 Nordea Bank Finland Plc. Internal Service and Premises. Sörnäistenkatu 1. FI Nordea. (Helsinki) Finland. Mobile: Fax: Juha.Olkinuora@nordea.com 2 Nordea Bank Finland Plc. Internal Service and Premises. Sörnäistenkatu 1. FI Nordea. (Helsinki) Finland. Mobile: Fax: Reijo. Kaurela@nordea.com 1. INTRODUCTION The Nordea Group is committed to the Declaration on Banking and the Environment, a Statement by the Banks on the Environment and Sustainable Development issued by UNEP, the environment organisation of the UN, in The Nordea Group does its environmental work within the framework of a confirmed environmental policy, annually updated environment programmes and environment work plans drafted for individual workplaces and business sites. In addition to the environmental impact of commercial activity in general, Nordea s own activities play an important environmental role. As a major real-estate owner and employer, the Group wants to develop its building stock in a direction that will decrease the load on the environment and improve the well-being of its employees. The aim of the Aleksis Kiven katu 9 project was to develop an office building model for Nordea Pankki Suomi Oy that would fulfil the ever-growing demands of the future both ecologically and as a working environment. Premises that enable a top work performance also enhance the bank s profitability and employer image. 2. THE PROJECT ENVIRONMENT Aleksis Kiven katu 9 is located at about five kilometres distance from the Helsinki city centre. It is easily accessible by various means of transportation, including buses, trams and the metro, as well as commuter bicycle lanes. The building is in the Vallila district in an environment of some historical value. It closes the corner of Aleksis Kiven katu and Fleminginkatu, thereby completing the hitherto incomplete block. During the design phase, particular attention was paid to the materials, colouring, roof shapes and height dimensions of the surrounding buildings. The building site had earlier served in various industrial uses. This historical heritage had left the soil widely contaminated, as studies carried out both before and during construction revealed. The polluted land (3,700 tons) was removed and transported to officially approved locations for reception and processing. Construction waste was recycled at a recycling rate of 85 %. The basement storeys of the building reach down 4 metres below the ground water surface. The ground water management relies on massive waterproof foundation walls cast in situ on the rock. The aim was to improve the environmental condition of the construction site without altering the ground water conditions unnecessarily. The building has two storeys under ground and seven office floors above ground. The gross surface area is 14,334 m 2, the floor area of the office floors is 9,264 m 2 and the cubical content

2 50,620 m 3. The construction work began in March 2000 and the building was completed in July In November 2001, Aleksis Kiven katu 9 won the Finnish environmental project competition in the field of real estate and construction. The jury evaluated the environmental aspects of the project on the basis of the Environmental Assessment and Classification System for Buildings developed in Finland. Aleksis Kiven katu 9 scored high on all aspects, but the judges particularly praised the systematic work done on indoor air quality. 3. LIFE CYCLE EFFICIENCY After the plans had been completed, an independent consultant carried out life cycle assessments of the energy use in the building. The assessments comprised the energy use in the building by a method of simulation and analyses of the use of displacement air in the garage, free refrigerating and solar shading. The life cycle assessments were also used to select the supplier of ventilation equipment from competing products. As part of the life cycle assessment, the indoor air conditions created in the office spaces were observed against the planned efficiency values of the HVAC plant as well as internal and external loadings. Table 1 plan). Aleksis Kiven katu 9, estimated annual energy use (with solutions according to Type of energy Total consumption Specific consumption Reference figure 1 MWh/ a kwh/a kwh/a m 2 m 3 m 3 1. Heating ,7 31,7 - Radiators 415 8,2 - Ventilation 468 9,3 - Warm service water 61 1,2 2. Electricity ,8 15,4 28,2 - Cooling 48 3,9 - Fan ,9 - Lighting ,5 - Lifts 9 0,7 - Others ,8 1) Average specific consumption according to the monitoring system of The Finnish Information Centre for Energy Efficiency and Renewable Energy Sources, Motiva Oy. No exact age goals were set for the building or its parts. However, structural solutions that are known to be long-lasting were used in the frame, the elements, and the essential parts of the façades. The load-bearing structures consist of composite steel girders, low web girders and hollow-core slabs as secondary structures. A pillar grid (8 100 mm x mm) provides

3 flexibility in the use of space. Towards the inner court yard, the outer walls are concrete sandwich structures; on the street side, the concrete internal skin has a mineral wool insulation built in situ. The thermal plaster façade meets the requirements of both the urban landscape and the authorities. The service life of the principal components of the frame is over 100 years, that of the bearing parts of the external walls and the claddings about 50 years and the thermal plastering about 30 years. The office space windows are aluminium-clad wooden windows and the other windows are steel-framed and aluminium-lined window structures. The steel parts in the façades are hot galvanised and either painted or of acid-proof stainless steel. The roof is mainly spiral jointed, plastic-coated plate roofing and partly three-layer bitumen roofing made on the basis of the inverted roof. The leading idea of the building design is flexibility in the structures, the space lay-out and the installations of house technology. The height, façade structures and heating, ventilation, air-conditioning and electricity technology of the ground floor allow its use as a commercial space as well. The office floors can be divided between two users per floor. The fixed staircases, technical rooms and sanitary rooms are located at the ends of the building wings, enabling flexible solutions of indoor decoration. Upper wall parts pre-built along the corridors make the placing of the light partition wall elements of the office spaces easy to change. The structural flexibility was tested floor by floor during the application planning of the user s interior decoration needs. Additional electricity and data transfer network outlets and cables only needed to be installed in a few departments related to the company s dealing operations. 4. INDOOR AIR QUALITY IN THE BUILDING In the building design, particular emphasis was laid on indoor air quality in the occupied floors and a healthy working environment. The work followed the principles of the Healthy House operation model coordinated by the Finnish Association of Building Owners and Construction Clients RAKLI and supported by the National Technology Agency Tekes. The planning work was supported by the experience gained from the bank s extensive programme of workplace humidity management. In order to ensure a pleasant and productive indoor climate, the Laboratory of Heating, Ventilation and Air-Conditioning of the Helsinki University of Technology acted as an expert of indoor air during the planning of the building and the supervision of its construction. The work of the laboratory included the following steps: Checking the heating, ventilation and air-conditioning plans, work specifications and structural engineering plans from the point of view of the performance of moisture control techniques, building specifications and the choice of materials. Determining and monitoring the level requirements for the key factors of indoor climate and keeping the constructor informed of their status. Technical support for alternative solutions. Surface materials The effects of the furniture and fittings on indoor air Instructions for cleaning and ventilating during work on the site Measures during the construction phase

4 Technical support for scheduling, with special emphasis on ensuring the end result of the work on adjusting and balancing the air-conditioning Instructions for final cleaning and ventilation Measures during the reception phase Measuring the ventilation system hygiene Supervising the indoor climate checks Measuring the final ventilation Checking the texts on indoor air in the maintenance manual and suggesting appropriate improvements. Including the indoor air requirements in the maintenance agreements. Drawing up a plan on monitoring indoor climate and user satisfaction. During the project, the HVAC Laboratory went through technical and commercial documents, made calls, checks and measurements at the site and participated in site meetings in order to ensure that the work was carried out according to plans and set goals. The work laid particular emphasis on the following measures: Checking critical material choices in the building (the use of Class M surface materials = the best class of classified products in terms of emission characteristics) with the purpose of preventing harmful emissions. Preparing the procurement of movable furniture and fittings with the purpose of preventing the impairment of indoor climate (panels, fabrics and lacquers used and the ventilation of the furniture and fittings in the target project). Suggesting measures to ensure the hygiene of the ventilation system. Assessing the noise caused by the ventilation system and the sound levels at the critical points (it is, for example, easy to lower the noise level of the cooling compressors and the cooling beams during the construction phase, but very difficult after the building has been completed). Suggesting ways of fulfilling the sound isolation requirements of the system walls. Suggesting ways of carrying out the gauging and adjustment of the ventilation system within the tight schedule without compromising the hygiene of the system. Gauging the hygiene of the ventilation system and follow-up gauging after cleaning. Gauging the temperature control and air escape of the rooms.

5 Preparing the tender calls for property management and maintenance concerning indoor air. By continuously paying attention to the procedures of planning, procurements, construction, supervision and service and maintenance of the building in Aleksis Kiven katu 9, it was possible to fulfil the goals set for its indoor climate conditions so that Class S2 requirements of good indoor air quality (air renewal 2 l/s/m 2, air cooling and temperature control carried out for each room separately) were met. 5. FINALLY The best available professional expertise, a working method emphasising an efficient flow of information and a good end result, and a management method aiming at total success were applied during all the phases of the project. Perhaps the most important of all the crucial elements was the successfully accomplished, top-quality and precise implementation of the total project process. Picture 1 Aleksis Kiven katu 9, floor plan. Picture 2 Aleksis Kiven katu 9, plan cross-section.

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