St. Joseph’s Catholic Primary School, London

Project: St. Joseph’s Catholic Primary School, London

In 1851, Frederick Faber (a hymn writer and theologian who converted from Anglicanism to the Catholic priesthood), founded a religious charity to “educate and help local poor children” providing an Infant School, Boys and Girls Day Schools and Night Schools “for those boys and girls who, being employed in selling fruit, sweeping crossings and similar occupations, cannot attend school in the daytime” (Source: Catholic Directory 1856). Located within London’s Seven Dials Conservation Area, part of the original extensive building complex eventually become St. Joseph’s Catholic Primary School.

Several of the other original buildings now provide residential accommodation and the building located to the south side of St. Joseph’s, which overlooks classrooms and the school’s playground, is scheduled for demolition  to make way for additional, much needed social and private flats. The excessive noise generated from building works cannot be adequately contained by traditional sash windows and without some additional insulation there would be a damaging effect on classroom concentration. The World Health Organisation’s guideline for reasonable noise levels in classrooms is 35-40dB and consultant EC Harris, acting for the London Borough of Camden, recommended the installation of acoustic secondary glazing.

Selectaglaze, the UK’s leading designer of secondary glazing systems, was approached to develop designs that would provide the necessary noise reductions but also allow full access to the external sash windows, some with high level hopper lights, both for ventilation and maintenance. The Company has a wide range of laboratory tested products that will reduce noise levels by 40-45dB and has considerable experience of working within period buildings.


The solution was a slim balanced vertical sliding unit to match the sash windows and a high level horizontal sliding unit for the hopper lights. Ring pulls were applied to the upper sliding panels to allow them to be operated by the same pole that opens the hoppers and so ensure access to high level ventilation. Toughened safety glass was recommended throughout to reduce risk to pupils and staff.

Selectaglaze treated a total of 37 windows across all four floors of the school, providing a total of 69 frames, each of which was purpose made with high performance seals that not only improve the acoustic insulation but also help reduce the passage of dust and dirt, which is a feature of all building sites. The bespoke frames were fully fabricated off-site allowing rapid installation during a holiday period, thus minimising disruption for the school.

Camden Council also has a stated target of 40% carbon emissions reduction within schools by 2020. Many buildings use nearly half their energy supplies for heating, which is both expensive and wasteful. Secondary glazing traps an insulating layer of air between the windows and efficient seals will exclude draughts over the whole frame. It can, therefore, be an important retrofit solution to improving building energy performance either in combination with traditional single glazed windows or more recent double glazing, which then achieves a triple glazed combination.