central library helsinki

Open international competition 2012

Team:
Architecture Damir Masek www.damirmasek.net
Building services engineering Stefan van Velsen, David Thommen www.3-plan.ch
Structural engineer Stefan Baenziger www.schnetzerpuskas.com
Consultant Oliver Hildenbrand www.planixteam.ch

Architecture:

The project extends from the Secret Gardens landscape park towards the city and articulates the end of this urban context.

From the centre of Helsinki, the wooden structure emphasises the beginning a cultural expanse. There is a large tree-based structure on the route - the Helsinki Central Library.
Weathering refines Finnish pine wood and the material is alive.
The volume of the structure extends across to the park, levels off and creates spatial and visual connections.
The eyes (shells) of the library are open to the urban context (the centre of Helsinki, the cultural and institutional buildings, Kansalaistori piazza) and the landscape context and welcome visitors. The open ground floor welcomes guests from the library entrance on the south side and from the catering facilities on the west side of the building.
Each facade presents an individual face relating to the relevant urban or landscape setting thanks to the building’s fundamental structure – flatland ( stacked floors) east-west and gently rolling mountains (‘soft’ spaces).
The appearance of the project corresponds to both the inner structure and statics.
The gently rolling mountains (in the internal shells/ eyes) lead from floor to floor. Some face inwards and some outwards. The former open up all of the floors and the latter open up every other floor.
There is disabled access to all of the sequences of areas and levels. Small open lifts in the eyes/ gently rolling mountains offer access to all areas.
Visitors can adequately submerse themselves in the required content in the small theatres (eyes, shells) facing the city which offer a very peaceful atmosphere.  These felt-clad areas encompass excellent acoustics and are ideal for various uses and occasions. They do not open up all of the floors. They are covered with felt.
The varied lighting within the depths of the library enables users to access light-sensitive items (e.g. in the collection area) in dimmed lighting areas with no walls.
The flexibility of the interior room layout offers optimal conditions for the internal landscape. The primary zoning without room partitions creates a combination of a predominantly flat areas with gently rolling ‘hills’.
The following zoning nuances are available:

  • From the main floor (sea) leading on to the bays (fjord reference)
  • Located on slightly elevated and/or lowered levels and visually linked with the main room and/ or bays
  • In the room shells (eyes) on different levels, all connected with the main room
  • In the room shells (eyes) on different levels, self-contained

As in nature, visitors may gather around an elevated area, for example. Some will read on a slightly elevated level, others will stay on the main level. They form a unit, visually and acoustically speaking; they chat, discuss and study and read either individually or together.

 

Structural concept

The supporting structure primarily consists of wood. Only the foundations and the vertical development cores are made from in-situ concrete to guarantee horizontal stability and for fire protection purposes (escape routes are non-flammable). While the eastern train side in the bookcases area features a conventional structure of ceilings with wooden elements and vertical supports in an even pattern, the circulation and reading area incorporates an interconnected folded plate structure. The two-storey reading halls will be reinforced using the bowl effect of the ceiling elements and the slanted frame-like supports. The broadly projecting volume is made possible thanks to the plate effect of the vertical and sloping surfaces.

 

EXTENT INFORMATION

 

Floor

Roof

North

East

South

West

Technical space (not included in room programm)

1’275 m2

 

 

 

 

 

Gross floor area
(above ground)

17’680 m2

 

 

 

 

 

Photovoltaic panels

 

2’380 m2

 

1’015 m2

175 m2

 

Translucent fibreglass*

 

 

 

500 m2

30 m2

 

Glazing*

 

635 m2

270 m2

830 m2

260 m2

1’755 m2

Opaque façade*

 

 

150 m2

1’195 m2

380 m2

800 m2

Floor*

5’150 m2

 

 

 

 

 

Roof* (horizontal)*

 

4’235 m2

 

 

 

 

* areas of building envelope

EnergY SUPPLY SOLUTION

The technical solution has been devised in line with architectural standards and therefore suits the different utilization requirements as well as respecting the architectural draft.
As the main building material, Finnish pine is a natural, local and renewable resource and impresses with its low CO2 emission potential and its harmonious and aesthetically pleasing wooden appearance.
The building’s heating needs will be covered using the district heating network in Helsinki. The cooling of the building will primarily be solved through passive measures (e.g. well-balanced glazing ratio) and an effective natural night-time cooling concept. In addition, the cooling loads of the building can be kept to a minimum due to the energy efficient lighting devices and appliances and the optimal use of daylight. Restricted district cooling is used for special zones (e.g. cinema).
Electricity is produced on site using an extensive area of photovoltaic panels which are fully integrated into the buildings envelope and which contribute significantly to achieving the demanding energy performance value.
The electricity distribution network is based on floor-integrated channels in order to maximize the flexibility of the building. Easy access and adaptation to any new room requirements is possible.

HEATING

The low energy carrier factor of the Helsinki’s district heating network makes it a suitable source of heating energy to cover the new library’s heating needs.
The heat will be distributed through integrated floor and wall convectors which will be sensibly placed in the right spots and controlled through independent, easy to use, cost-efficient and distortion-free thermostatic valves.

STRUCTURES

The wooden structure of the local Finnish pine in particular promotes the ecological aspects of the project thanks to its low CO2 potential and local availability. The rear-ventilated wooden façade system increases the life expectancy of the building envelope and decreases the demolition complexity and time, all of which results in lower overall lifetime costs. For insulating, mineral wool is used.
Translucent, reinforced fibreglass elements filled with aerogel mainly cover the east side and parts of the south façade, giving a very good insulating to light-translucence ratio. Together with the very strict u-values of the building envelope (opaque elements u-value = 0.10 W/m2K), the need for heating energy has been minimised.
WINDOWS
A well-balanced glazing to opaque ratio combined with innovative electrically dimmable and insulated triple-glazing (ug-value ≤ 0.60 W/m2K) minimizes the potential for high external cooling loads in summer as well as preventing extreme heat losses in winter. The integration of electronically controllable electrochromic glazing also eliminates the need for external shading systems and their potential for damage in the high wind speeds.

LIGHTING

Daylight will primarily be used to illuminate the building. Therefore, the focus is on maximising the use of daylight and minimizing the use fo artificial lighting. The substantial depth of the building helps to separate daylight-intensive utilisation areas such as the reading spots along the façade from light-extensive areas such as the storage spaces in a very simple manner.
The building’s lighting concept plays a major role in its overall energy performance. Special care is given to this point with the use of energy efficient lighting (LED / fluorescent lamps) and their optimal room placement.
The traffic zones, as well as the ’eyes’ of the building, comprise a fixed lighting concept while the ‘flat-land’ area is designed to include standing, flexible, moveable lights which are easy to adapt to changing room requirements.

VENTILATION

The ventilation devices will be centrally placed in the basement of the building. The air ducts are integrated in the building’s body and are invisible to the visitors. In order to maximize energy efficiency, low air speeds and minimum pressure drop is essential.
Energy efficient motors and filters, ventilators with a high coefficient, optimal zoning, selective independent adjustable air distribution between the zones and CO2-dependent control lower the building’s electricity needs while contributing to a pleasant environment for visitors.
To minimize heat losses through ventilation, highly efficient, plan-integrated heat recovery is essential.
COOLING
The cooling needs of the building are kept to a minimum through the innovative electrochromic glazing, the efficient lighting devices and appliances, the optimally placed light sources, the use of daylight and the possibility of natural night-time cooling. For special zones (e.g. cinema) where active cooling is needed, this will be provided through Helsinki’s district cooling network with its very low energy carrier factor.

DOMESTIC HOT WATER

Like the room heating, hot water will be produced based on Helsinki’s district heating network. An insulated water storage tank, energy efficient pumps and water-saving appliances add to the ecological ‘behaviour’ of the new library. The public toilets will be supplied with only cold water.