Description
How to make a school which reflects two competing ideas, that of traditional cellular classrooms, the proverbial ‘machine for learning in,’ and a humane place which truly reflects the world of the future, within which its key users, the pupils, will be living decades from now?
Understandably most contemporary architects will look to the knotty issue of sustainability, controlling global warming by minimising the carbon footprint and endeavouring to jangle the child’s awareness with bolt-on goodies such as wind turbines and solar panels. Often costs will soar and the project budget will be cut back; that dreaded phrase ‘value engineering’ will be utilised by the client’s quantity surveyor to politely request cost reductions. This process can dilute the architect’s original vision to the point where the sustainability agenda is all but lost. This has not been the case here.
The new school at Hohen Neuendorf is for an expanding town 15 km north of Berlin. The brief required a primary school for children aged 6-11 years, with each age group comprising three forms of entry (90 children in each unit), with a total of 540 pupils across 18 classrooms. In addition there was to be an integrated triple field sports hall with community access during evenings and weekends, facilitating all sorts of additional activities for parents, grandparents and other members of the extended family. It has a real community dimension, potentially opening education up to everyone for their lifetimes.
Therefore it needed to be robust to resist generations of use and organised in such a way that it retains a sense of small-scale departments within a larger whole. So each age-orientated group of three classrooms takes its place within three clearly defined wings of accommodation on two storeys. Each is orientated with a closed façade to the north and a more open south-facing façade. The designers have adopted well-known typological moves drawn from a rich history of school design, with a linking ‘street’ of accommodation running south to north (from the main entrance) forming a lively social spine for the new building. There are in addition staff offices, a dining room with a connected kitchen/multi-purpose hall and a small library.
In consultation with the school teachers and the designer’s deeply scientific understanding of sustainability a ‘home concept’ – as they describe it – has been developed for each group of 30 pupils, a sequence of linked areas comprising a traditional classroom with a smaller workroom directly off it; this is connected by a circulation space which is subsidiary to the main ‘street’ circulation spine, leading from the classrooms to a children’s washroom and cloakroom. The whole creates a logical organisation around which the entire concept for ventilation and lighting can take place. These are the age-old problems of school design, where cooling is more critical than heating, and it is where this project gets really clever.
For the head of design, Ingo Lütkemeyer, the unambiguous solution to the overheating problem is firstly thermal mass. Based on the simple concept that a cave is always cool no matter how hot it is outside, whereas a tent gets hot instantly when the external temperature rises, the fabric of the building, predominantly the heat generating roof areas most exposed to the sun, has to be made of a heavy material. This will ameliorate external solar gain, soaking up the sun’s energy without stress. Therefore the entire roof is constructed of concrete, in heavy pre-fabricated panels.
Secondly, a so-called hybrid ventilation system, that is a combination of natural and forced mechanical ventilation to the grouped homebases deals with variable occupancy conditions. During break times, when children are outside, air pours into the hot classroom spaces by way of large window sized vent panels. These are motor controlled and full height to completely aerate the space ready for the return of the children who will have been running around and ready to generate their own heat build-up. As they settle back into their lessons and the CO
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levels begin to rise once more, a mechanical form of ventilation is required to freshen stale air, however only small amounts are required, so traditional full air conditioning is avoided. The supply airflow for the classrooms correlates to the levels of external exhaust needed for the sanitary units, thus air is sucked out from the classrooms and through the toilets to provide the most efficient use of power.
These two key ideas are the fundamental principles around which the building’s sustainability is predicated. Numerous other features add to the overall efficiency, for example thermal comfort during the hot summer periods is achieved by means of passive night cooling using the motor controlled vent windows to air the large areas of thermal storage mass, freshness which is then carried forward to daytime. A sophisticated south-facing façade with automated external blinds and the use of nanogel glazing to diffuse heavy solar spray, provides optimum natural light to the deep plan thus minimising the use of electrical lighting. Here the orientation of the building’s windows is critical and shapes the internal form. Combined with the use of renewable energy resources such as wood pellets for heating and integrated photovoltaic panels across the entire roof, this building provides 25% life cycle cost savings.
Drawings
Photos
Exterior view from Goethestraße
View of interior circulation area
Originally published in: Mark Dudek, Schools and Kindergartens: A Design Manual, Birkhäuser, 2015.