Manufacturer’s parallel opening window vents feature at the Anna Freud Centre.

Parallel opening window vents by leading manufacturer of architectural glazing systems Kawneer were specified for a mental health project that is arguably without parallel.

Some 88 of Kawneer’s AA®100 SSG parallel opening vents were used as concealed windows, to maintain the same aesthetic as the façade, within AA®100 mullion-drained curtain walling and AA®720 doors on the new £40 million London headquarters of the world-famous Anna Freud National Centre for Children and Families.

The Kawneer systems were specified by architects Penoyre & Prasad as they were a “cost-effective” solution to their needs and enabled them to use the same systems for all areas of curtain walling and rooflights.

Architect Sam Frankland said: “We had an aspiration to create a very clean, paired-down façade that would give clear cohesion to the various buildings. Having scissor-action windows helped emphasise the planar quality when the windows are open.”

The project has enabled the relocation of the mental healthcare charity to bring together its global expertise in practice, research and policy under one roof from its residential properties in Hampstead to a purpose-built facility near King’s Cross. This comprises a six-storey new-build and the refurbishment of a century-old former chocolate factory and warehouse.

All of the Kawneer glazing systems feature a diagonal frit on the glass, with the Kawneer curtain walling featuring on the ground to top floors and the AA®100 SSG parallel-opening vents on all but the ground floor. The AA®720 doors feature on the main entrance and top floor which also features a roof terrace.

Sam Frankland added: “We wanted to create spaces filled with light and views out over London so we opted for fully-glazed panels with a simple frit to give an element of privacy and a degree of visual interest to the façade.”

The aluminium Kawneer systems were installed over eight months by a team of six from approved specialist sub-contractor/dealer JPJ Installations for main contractor Willmott Dixon.

The charity that today bears the name of Sigmund Freud’s sixth and youngest child was first established almost 70 years ago and its approach, that every child and its family should be at the heart of the care they receive, working in partnership with professionals, has been reflected in Penoyre & Prasad’s design.

This needed to be striking to reflect the charity’s aspirations to reflect its status as a world-renowned organisation working with eminent academic institutions as University College London and Yale.

This itself presented a challenge, bringing together the multiple needs of the individual users of the building, from children and their families in need of support, to researchers, clinicians and internationally-renowned visiting academics attending symposia.

At the front, in the space made vacant by the excavation of a former courtyard, is the new six-storey building housing shared conference facilities and the Pears Family School which is sponsored by the Anna Freud Centre. This caters for up to 48 youngsters who have been excluded from school or alternative education provision and helps them return to mainstream education.

Penoyre & Prasad worked from the outset with the diagonal motif on the glazing on both the front and rear facades to inform both the transparent elevation and the precast cheeks of the building which they could do very little with as they were both party walls but which nevertheless replicate the diagonal fritting.

The five-storey chocolate factory, parts of which had been used as offices since the 1990s, was converted into a combination of head office facilities and therapy, post-graduate teaching and research (part of which had been based at University College London) and break-out spaces for the Anna Freud Centre.

Although not listed, heritage officers at Islington Council had still been anxious about how it would be developed.

“The client was very keen to have as environmentally friendly a building as possible so aluminium seemed like the natural choice for the curtain wall system which has been used extensively to the east and west facades and as a large rooflight,” said Sam Frankland.

Based on the established Kawneer AA®100 SSG POV system, the parallel opening design benefits from excellent ventilation characteristics combined with thermal performance.

Increased air flow around the full perimeter of the window enables highly efficient natural ventilation while greatly reducing draughts as fresh air is drawn in the bottom of the window while warm, stale air is expelled via the top, creating full air circulation within a room.

This efficient exchange of air can assist with Approved Document F compliance and can enable the window to meet the ventilation requirements of even the most demanding project.