INCA: 40 years young!

external wall insulation

Above: Dumfries and Galloway Housing Partnership: Winner of EWI with a traditional finish

INCA, the Insulated Render and Cladding Association, is celebrating its 40th year and is now established as the leading organisation representing the external wall insulation industry. Technical standards and excellent workmanship are core to INCA’s values, with the annual INCA Awards event highlighting the best projects from the industry completed in the previous 12 months. The winning projects demonstrated a wide range of completed projects in both the refurbishment and new build sectors including many local authority and social housing schemes using a wide range of innovative finishes.

External Wall Insulation is a technology employing insulation boards fixed to either masonry walls in a refurbishment setting, or to the sheathing layer of new build schemes built with steel framing or with a concrete frame with SFS infill. Beyond these common construction types, other less prominent building methods such as timber frame, ICF and offsite construction can also benefit from the use of EWI. System designers of EWI systems provide project-specific specifications outlining the adhesive and mechanical fixings of the insulation boards and the systems are finished with either high-grade decorative coatings or brick slip finishes.

External wall insulation is an energy-saving, fabric-first measure, targeted in various central and devolved government schemes, the most recent being the Decarbonisation Fund and ECO4 programmes. With the current UK housing stock urgently requiring energy upgrades to solid walled properties, opportunities to find suitable communities to benefit is high priority for social landlords where the positive outcome extends well beyond the energy efficiency benefits for landlords, residents, and the wider community.

external wall insulationINCA’s Refurbishment Awards recognised the use of EWI in upgrading existing buildings and this year featured a wide range of examples of traditional masonry as well as non-traditional properties being thermally improved and visually transformed.

The winner of this year’s EWI with a render finish is a large-scale high-rise project. In July 2020, K Systems completed a major refurbishment of Fitzwarren Court, one of the highest residential buildings in Salford, delivering a modernised aesthetic and improved thermal performance. Extensive evaluations of systems and materials took place with Hamilton Contractors to identify the best combination to achieve a clean and contemporary finish, improve the u-value of the properties and ensure compliance with building regulations in England for high rise buildings.

The client desired a clean, slick finish whilst residents, involved at design phase, requested a more contemporary aesthetic than the previous blue and green façade. K Systems applied a unique combination of VBriQ acrylic brick slips and Silkolitt render finish in contrasting colours to achieve an eye catching and textured exterior.

The refurbishment, taking place with some Covid restrictions still in place, wasn’t without its challenges. However, K System’s technical teams remained on-task and committed to delivering excellence, making regular site visits to guarantee the highest standards of workmanship including old expansion joints and lintels dubbed out, fire fixings secured through mesh and panels, bespoke vented gas plates fitted, joints accurately sealed and surfaces without undulations.

Through expert vision and innovation, K Systems delivered an outstanding refurbishment and proudly played its part in the regeneration of this deprived area in Salford.

Demonstrating that remodelled commercial buildings are equally suitable for EWI systems is the is Palmyra House in Warrington, winner of INCA’s award for EWI with a brick finish. Aliva UK’s external wall insulation system has transformed an old, dysfunctional office block into high-end residential apartment blocks and commercial spaces for Torus Developments.

The system had to improve the aesthetic that had been approved by local planning officers including lightweight brick slips, feature cills, heads and reveals to replicate stonework as well as a feature parapet.

The existing building was formed by a concrete frame in need of concrete repairs; a brick infill with minimal cavity behind creating a poor u-value of 1.2W/m2k. Aliva worked with Hamilton Contractors to carry out the installation of the EWI system. Aliva supplied their Thermok8 Minerale System comprising of 90mm Mineral Wool insulation, reinforced cementitious basecoat render and a lightweight brick slip in red multi and buff colours to achieve 0.28 W/m2k. The end result was further complemented by projecting feature bands with a textured finish and taped to replicate a stone joint.

The area of Palmyra Square has been transformed with the addition of this newly refurbished building, complying fully with BBA Certificate 11/4841.

external wall insulation

Above left: Palmyra House in Warrington won the ‘External Wall Insulation with a brick finish’ award
Above right: Blackstoun Oval project picked up the Environmental award for its deep retrofit approach

Using EWI to retain the traditional finishes of the local vernacular was the inspiration behind the INCA award for EWI with a traditional finish and was a worthy winner.

Dumfries and Galloway Housing Partnership has signed a contract worth up to £8m to include investing in new external wall insulation. Tenants in around 800 DGHP homes will benefit from an improved external appearance, increased energy efficiency, and reductions in the cost of heating their homes as a result of the award of the contract to SERS Energy Solutions (Scotland). SPS Envirowall’s external wall insulation system was fitted to 562 properties. All gas meters and risers were moved to allow for insulation behind to minimise thermal bridging. All roof gables and eaves were required extending to accommodate the extra thickness of the EWI system. The system selected utilised 90mm graphite EPS insulation, finished with a traditional dry dash.

All works were conducted while the properties were still occupied. RLOs and site managers worked hard to manage the customer interface to keep residents well-informed and safe, as well as ensuring a safe working environment for operatives. Local subcontractors were employed where possible, and with help from Envirowall, EPS waste was recycled.

Chairman of DGHP, Robert Higgins, commented “The £8 million programme will provide much needed investment in properties across the region and is indicative of the commitment of DGHP to improve tenants’ homes.”

Recognising environmental benefits and energy conservation was the winner of this distinct category, Blackstoun Oval in Paisley. Renfrewshire Council’s ambition was to provide intense retrofit measures to inter-war properties making them suitable for modern living. Installed by Procast to meet PAS2030:2019 involved roof extensions, insulation below dpc level to fully encapsulate the buildings, and modifications to surface mounted services by removing and fitting insulation behind – designed to maximise thermal efficiency. This project not only realised the client’s vision, but it also demonstrated exemplary work towards a greener future where energy efficiency measures can be installed using the PAS2035 ‘whole house approach.’ Procast’s Barry Chisholm summed up the project “This project presented a number of challenges and difficulties, all exacerbated by Covid 19 and trying to adapt our working practices to PAS2035. Structherm’s unparalleled technical and commercial support from building warrant stage through to completion ensured that Procast were able to deliver Renfrewshire Council’s vision of exceptionally deep retrofit on these 1930s houses turning them into houses for the future.”

external wall insulationOther notable winners in the awards were installer AC Whyte for their Energy Efficiency Skills Academy giving thirty-six local candidates from deprived areas an opportunity to learn a trade, attain a recognised qualification and become full time EWI installers upon successful completion, becoming part of Scotland’s ‘carbon army,’ creating up to 22,000 jobs by 2028.

Specialist EWI component suppliers Swifix and Trueline were winners in the Innovation and Component Supplier awards respectively and Hamilton Building Contractors were praised as Installer of the year.

For more information including the online Awards brochure featuring these and all winning and highly commended entries, visit

external wall insulation