Two new apartment buildings in Kent have been given a thermally-efficient and visually-striking façade thanks to the use of an external wall insulation system from Sto. The two new blocks in Ashford - Stour Heights and Somerset Heights – have a single-skin construction, comprising a reinforced concrete frame with concrete block infill, and they benefit from the installation of StoTherm Mineral external wall insulation, with a StoCleyer B mineral brick slip and StoSilco render façade finish.

“An alternative insulation system was originally proposed for these buildings,” says John Mahoney of Sheffield-based J Mahoney Architects. “As things progressed a different solution was required to meet the demands of the various parties involved in the project. Sto pretty much leads the pack in terms of quality, and the StoTherm Mineral system was able to satisfy everyone’s requirements, so it became the obvious choice. The fact that Sto could work with us and provide technical support was also extremely helpful.”

The BBA-certified StoTherm Mineral external wall insulation system uses mineral-fibre boards to provide outstanding thermal performance, combined with reliable fire protection and effective sound insulation. Its efficient single-leaf construction and external installation do not compromise the building’s interior space, and it can be installed without the need for additional expansion joints.

For the new buildings, it was installed using Sto’s unique Sto-Rotofix plus mechanical fixing system. The helical Rotofix fixings create a cavity behind the insulation board, which can be easily adjusted after installation to ensure a level outer surface is created. This system combines the ease-of-use of ETICS anchors with the flexibility of a mechanical rail system, but without the material and labour cost of installing the rails.

“The StoCleyer B brick slips were specified to meet certain planning requirements,” adds John Mahoney. “An alternative brick solution was originally considered, but Sto was able to manufacture slips which were a perfect match for the proposed original. The fact that they were also fully compatible with the Sto insulation system was another significant point in their favour.”

StoCleyer B mineral brick slips are manufactured from synthetic render and provide an attractive, durable and weather-resistant finish, but with a realistic brick appearance. They have full BBA certification, and are available in either standard sizes and colours, or can be made to bespoke specifications, allowing architects to enjoy unlimited design freedom.

A StoSilco stippled render finish was also used on specific areas of the new buildings. This silicone resin render provides rugged protection and high levels of water repellence. “We were able to specify this in a white colour, and also a bronze-tinged brown which harmonised with the buff colour of the brick slips to create a really pleasing appearance,” adds John Mahoney.

The new buildings have added 109 one- and two-bedroomed flats which are spread across the five floors of Stour Heights, and the three floors of Somerset Heights.