Oak Meadow Primary School is one of the 1st three primary schools in the UK to receive Passivhaus certification in February 2012. Designed and built to the rigorous Passivhaus standard the two-form entry primary school (420 children) also includes facilities for a local ‘Mast Agency Support Team’.
The building, orientated on an East-West axis has been modelled to meet the technical demands associated with Passivhaus, which has influenced every decision about form, design and detailing, whilst ensuring focus has remained on simplifying and optimising the design.
The school has been constructed from a simple and robust palette of materials including; timber cladding, zinc roofing, timber windows and doors externally, timber screens, natural linoleum, organic paints and stains internally. Architype have been providing a series of ‘soft landing’ sessions, easing the occupiers into the building operations and guiding them to achieve optimal use of the building.
- Completion / Sept. ‘11
- Gross Internal Floor Area
- 2,300 sqm
- Construction Type
- Timber Frame
- Total / £4,900,000
The Design Aspirations and Key Principles
During the design development we aimed to:
- Express the warm, loving atmosphere of Oak Meadow School which has been so evident to us during the consultation .
- Enhance the school’s identity as a haven of security and calm in a city environment .
- Fulfill functional requirements within a careful zoning of uses .
- Create a dynamic range of stimulating spaces for teaching and learning .
- Achieve effective but unobtrusive security for children and staff .
- Ensure that the practical support and circulation spaces work simply and effectively .
- Create a delightful, airy and uplifting building made from natural, sustainable materials .
- Maximise natural daylight and ventilation, to create a healthy environment.
The highly insulated building fabric keeps the building cooler during the summer months. Solar heat gain is controlled by the brise soleil.
Summer ventilation is provided by opening windows and ventilation panels.
Air from outside enters the classroom and passes through into the hub space. Air leaves the building through high level vents in the hub space.
Heat is contained within the building by the highly insulated airtight walls, and the triple glazed windows. The building is heated by solar gains and radiators that can be individually controlled.
A central heat recovery system supplies fresh air to classrooms via supply grilles, air is then extracted through grilles from classrooms to hub spaces.
Windows and ventialtion panels can be opened to supply air direct from outside, however heat will be lost.
Building Design Concept
The massing of the building responds to surrounding historical agricultural grain, within a wider site boundary echoing the field boundary and ‘green corridor’ context of the previous occupation on the site. The proposed building sits within wider grass playing fields and grass ‘soft-play’ bounded by expanded and extended ‘green corridors’.
The proposed building form echoes the Saxon ‘Longhouse’ with an elongated footprint oriented East-West, with pitched roofs meeting centrally at the West elevation, expressing a central ‘circulation’ axis from which the majority of the accommodation is accessed.
All of the classrooms are oriented North-South (to maximise environmental control) with the majority facing due South. The elevational materiality reflects the educational and adult/service divide, along the East-West axis with a timber and glass clad more ephemeral Southern elevation ‘plugging’ into a solid timber Northern block, whilst maintaining a visual axis of transparency throughout.
This school has been designed from the outset to meet the energy standard, Passivhaus. This standard represents European best practice in terms of insulation and heating requirements, and also sets limits on total energy use and summer overheating. Passivhaus differs from zero carbon in that it primarily assesses the building fabric, rather than the fuel used. Passivhaus sets a finite limit on the heating energy demand; Oak Meadow uses some energy for heating, but only a tenth of typical new buildings. Given the low heating demand, and the focus on efficiency for lighting and computer use thats needed to meet the Passivhaus total energy requirement means the school meets the 60% carbon reduction target using gas heating and no renewable energy generation.
Passivhaus is simply a quality standard that guarantees performance. Its true value rests upon the assurance that its performance claims are both credible and reflect a genuine benefit to both the user and the environment, including:
- Minimised energy consumption.
- Avoidance of building defects that can lead to mould growth.
- Excellent standards of thermal comfort (satisfying ASHRAE55 and complying with EN7730).
- Minimised energy bills.
- High standards of indoor air quality.
- Optimised lifecycle costs.
Oak Meadow Passivhaus strategy
Roof 0.10 W/m2k
Walls 0.13 W/m2k
Floor 0.064 W/m2k
Windows 0.9 W/m2k
Oak Meadow achieved an Air Tightness level of 0.48a.c.h m3/hr/m2@50Pa, well below the Passivhaus requirement of 0.6.c.h m3/hr/m2@50Pa.
Heating / MVHR, gas condensing boiler
Ventilation / Natural ventilation & MVHR
Other features / Automated windows and manual night vent. In winter mode, air is supplied to all rooms and extracted through main hub space by internal ventilation louvres.
- M&E engineers
- Ernest Griffiths
- Structural Engineers
- Price and Myers
- Smith Thomas Consult
- Landscape Architecture
- Coe Design
- Passivhaus Consultant
- Elemental Solutions
- Winner of Non-domestic Category of the UK Passivhaus Award 2012