Bolton Sixth Form College Development

Another leading educational project uses Schöck thermal break modules

Since receiving the official go ahead for a major £21m development from the Learning Skills Council, Bolton Sixth Form College is now fast taking shape and due for completion next September. Situated on Deane Road, opposite the University of Bolton, the college is in the heart of the town’s £300m Innovation Zone, an area which includes 30 hectares of space consisting of a mix of high quality office space, leisure facilities and residential build, all of which complements the University and surrounding colleges.

Consistently ranked amongst the highest performing colleges in the country and providing a diverse range of advanced level and vocational courses, the new campus will see the creation of a high quality learning environment focused on the needs of 16 -19 year old students. Steve Wetton, Principal of Bolton Sixth Form College comments: “This fantastic development will be completed in time for students who are currently in year 10, providing them with high quality education and training, and enabling them to continue their studies in what will probably be the best resourced campus in the country.”

The new three-storey building has a structural steel frame and with steel being such a highly conductive material, combating any possible problems caused by thermal bridging was a major consideration early in the design stage. Thermal bridges occur where the insulation layer is penetrated by a material with a relatively high thermal conductivity and at interfaces between building elements where there is a discontinuity in the insulation. One of the consequences of this is local heat loss, resulting in more energy being required to maintain the inter-nal temperature of the building. While this is a very important aspect of thermal bridging, there is a more serious issue as far as building occupiers are concerned. Low internal surface temperatures in the area of the thermal bridge can cause condensation if they are below the dew point of the air. This in turn can lead not only to structural integrity problems with absorbent materials, but the occurrence of mould growth – which can have serious implications for the occu-pants in the form of respiratory problems – something to be avoided in any building, but certainly in educational establishments.

There are very few effective solutions to combating the various negative aspects of thermal bridges, particularly in steel structures. However, one proven answer incorporated into many of today’s high-profile educational buildings is the Isokorb® thermal break module; developed by Schöck, the European market leaders in this technology sector.

It is the Isokorb® type KST-QST 16 modules that are designed into the structure at Bolton College, units developed specifically for connections involving steel-to-steel free-cantilever, canopies, balconies and walkways. On this occasion the KST has been delivered as a special with non-standard bolt lengths. This is help the steel contractor on site who has to install the units in such a way as to accomodate precise fixing dimensions between the façade and a hollow box section.

KST modules from Schöck are unique in being able to withstand extremely demanding loads and are made from stainless steel components to ensure corrosion protection and minimise thermal conductivity. Due to their thermal insulation properties, the Isokorb® modules dramatically reduce energy loss in connective areas by guaranteeing that there is uniformity between cantilever structures and the internal structure at the thermal envelope. They also transfer load and maintain full structural integrity, while at the same time enable inner surface area temperatures to remain well in excess of those likely to cause mould for-mation and condensation.

The Isokorb® complies with the UK regulation which requires that the temperature factor used to indicate condensation risk (fRSI), as described in BRE IP1/06; a document cited in Building Regulations Approved Documents Part L1 and L2; must be greater than, or equal to, 0.50 for commercial buildings. A requirement comfortably exceeded by incorporating the Isokorb® KST 16 into the design with its fRSI performance rating of 0.82.⁽¹⁾

There is also compliance with the Government Standard Assessment Proce-dure, SAP 2005, concerning CO2 emissions from buildings, and respectively heat losses through non-repeating thermal bridges. Here, the λ-values of the Schöck Isokorb® enables energy loss through balconies, canopies and other cantilever parts of the building to be reduced by as much as 84% to 91%.

In addition to its exceptional thermal performance ratings, the Schöck Isokorb® range is also unique on two counts. It is the only range to provide thermal break solutions for connections between concrete-to-concrete, concrete-to-steel and steel-to-steel – and it is also able to offer BBA Certification for the concrete-to-steel range, with certification for the KST imminent.

There are more than two hundred and fifty standard solutions available in the Schöck range and modules can be tailored to suit practically any application, with different types enabling the transmission of shear, bending moment and tension, as well as compression.

A 20 page ‘Specifiers Handbook‘ is available which provides an overview and introduction to the Schöck Isokorb®, and there is a thoroughly comprehensive 236 page ‘Technical Guide’ which displays in detail the complete range of ther-mal break applications for all construction types – concrete-to-concrete, con-crete-to-steel, steel-to-steel and concrete-to-timber.

(1) The Steel Construction Institute (SCI), sponsored by Corus, has published a docu-ment entitled ‘Avoidance of Thermal Bridging in Steel Construction’ and the Schöck KST unit is the only product identified to provide full compliance with Part L for heat loss prevention and mould growth / condensation prevention