When it came to the design of a new classroom block and assembly hall at a leading independent school in Essex, an approach that both complemented and enhanced the school’s original 19th century construction was a key element of the project brief.
Founded in 1557, Brentwood School has carried out a number of refurbishment and new build projects as part of its expansion over the past 10 years including a sixth form study and social centre housed in a refurbished late- Victorian vicarage. The latter forms the main street frontage to the senior school with the new build facilities sitting impressively either side. This stunning transformation required brickwork detailing of the highest order. The
redevelopment of the prep school also required first-class brickwork, with the striking colonnade of brick arches and the facades of a new classroom block and assembly hall building enhancing the educational setting.
Designed by Cottrell & Vermeulen and built by contractor Rooff, the construction of the new buildings saw IG Masonry Support play an important part in the provision of a number of prefabricated brickwork solutions including the interlocking brick slip arches that enabled the architect’s vision to be realised and helped with the build sequence along with the quality finish. Creating new buildings that pushed the boundaries in terms of brickwork design while meeting conservation and planning requirements necessitated close collaboration between client, architect, contractor and IG Masonry Support’s project engineers.
With a brief to achieve a consistent colonnade of seven interlocking arches as well the masonry support requirements to achieve the required brickwork formation, IG Masonry Support manufactured and supplied a range of prefabricated components that met the design requirements and the wider considerations around planning in this heritage context. The offsite manufactured solutions also overcame challenges when it came to the creation of half arches that would have been impossible to build in a traditional way. IG’s Welded Masonry Support (WMS) is a rigid masonry support system comprising a stainless-steel angle support shelf with fixed brackets. Able to accommodate loads of up to and exceeding 14kN/m, it is fabricated to engineers’ specifications on a project basis and offers two planes of adjustability onsite. Offering ease-ofinstallation, the system can be supplied in a variety of configurations depending on the project’s requirements.
In this instance, a combination of restrained and self-supported solutions, the prefabricated brick arches required coordination with the concrete
superstructure. The connections had to be bespoke for every arch because the faces of the arches were semicircular and the concrete structure behind was chamfered. Another challenge that was overcome through engineering were the connections at the spring points. The connections between individual arches had to be designed to allow for differential movement. Connections at spring points had to therefore take into consideration the lack of space during installation due to the proximity of the column behind. Furthermore, the end half arches could not be built traditionally, with the only other option being to use concrete pre-cast which would be very heavy and difficult to install.
In terms of masonry support and the unusual brick bond pattern, masonry support was designed to take into consideration the unusual distribution of the load within the façade and required extra brackets. At the corners, further innovation on the part of IG was required due to the corner arches returning along the elevations and corner lintels requiring extended bearing zones.
Commenting on the solutions provided by IG Masonry Support, Jonathan Dawes, Associate at Cottrell & Vermeulen said: “We wanted to create a series of intricate arch details that would have been unachievable in conventional brickwork. The technical support we received from IG Masonry Support allowed us to realise this ambition.”
