Education

A series of Index sedum green roofs and living walls at the newly opened Northwood primary school in Darlington replicate the nearby ‘patchwork’ colour of the local allotments set amidst their dense urban environment of rows of terraced housing.

Northwood primary school is a £6.5million regional pathfinder project providing 420 young pupils with an environmentally friendly place of learning. The school has been set in a southerly direction to make the most of solar gain.

In the teaching areas roofs curve over the first storey sloping down, to be cut off by a run of double glazed windows fronting a narrow terrace which gives older pupils a view of the colourful patchwork appearance of the sedum plantings immediately below.

There is an open teaching area and on the ground floor windows of different heights allow viewing and natural light for younger pupils.

The Index Extensive Insta sedum system covering some 1,800 m2 of roof incorporates a prominent alu vapour control layer with 120mm of PIR insulation.

The following Helastoplay membrane is protected by Defend H Anti-roots over which a water retention mat and 75mm of naturally occurring substrate was laid to receive the Insta mat of sedum.

Firestop, a specialist membrane with flame retardants added during the manufacturing process, was used on all exposed details.

The two areas of living wall at the entrances to this timber-framed building are hung with pre-grown evergreen perennials and herbs, served by an automated zonal irrigation system.

The Index green roof will not only help to reduce CO2 emissions, but the vegetation will also absorb and slow any immediate fall of rain, some of which is directed to serve the toilet flushing system.

The roof mass doubles the life of the Index waterproofing to something like 50 years and it passively provides extra insulation to the structure, reducing heating costs.

A biomass boiler using locally sourced wood chippings and a balancing pond further enhance the BREEAM rating of the building.

The new school has been built on existing playing fields to reduce the need for temporary accommodation and in due course the old buildings will be demolished and playing fields laid over that site.

At an early stage of the construction a roof mock-up was provided with the Index waterproofing in place together with plugs of sedum so the pupils of the old school were able to use it as an active learning aid as they saw their new school building develop.

The architects for the project were Atkins Global Architects.

www.indexbp.co.uk