Project Overview:
Background:
In 2017, PermaRock took part in a 26-week energy efficiency demonstration project at Newark Crescent in Nottingham. It was part-financed by the REMOURBAN Project (“REgeneration MOdel for accelerating the smart URBAN transformation”) - a European-funded regeneration model, supported by various partners including Nottingham Trent University, Nottingham City Homes (NCH) and Nottingham City Council's Enviroenergy team.
The specified energy efficiency measures included the installation of new external wall insulation, new glazing and doors, replacement central heating boilers and new LED lighting. Some properties would also have energy monitors fitted to gauge the effects of the various energy saving measures.
It aimed to provide a blueprint for industry best practice. Using funding from the European Union and the Energy Company Obligation, it was part of a broader demonstration project showcasing carbon saving measures across four local sites.
Here, the work focused upon seven 3-storey No-Fines concrete blocks in the Sneinton area, close to the city centre, which were home to a mix of social housing residents and private leaseholders.
The Brief:
As a demonstration project, the scheme called for the use of multiple energy efficiency measures, with the use of external wall insulation considered to be the most important. Others included new glazing and doors, replacement central heating systems and new LED lighting. Energy monitors would then gauge the effects of the various measures.
Design and Specification:
The external wall insulation system chosen for the project was the PermaRock EPS-Premium System, comprising of 90 mm graphitised polystyrene insulation adhesively bonded and mechanically fixed to the no-fines concrete substrate. Over it, a PermaRock reinforced basecoat was applied, followed either by PermaRock SiliconeULTRA K-Finish in two colours (Cool White and Granit 30) or PermaRock Brick Slips (colour: Moorland with grey pointing mortar). The brick slips were applied in a standard stretcher bond with a brick soldier course at the bottom of each panel.
PermaRock Mineral Fibre Insulation – in the same thickness as the EPS-Premium and adhesively bonded and mechanically fixed through the reinforced basecoat – was introduced at all compartment wall and floor lines to provide fire breaks within the system.
PermaRock Mineral Fibre insulation collars were also used around flue penetrations to protect the EPS insulation against possible high-temperature gases emerging from the boiler flue outlets.
Aesthetic concerns were also important so, prior to commencement on site, PermaRock system designers spent considerable time producing visualisations and detail designs in order to secure planning consent. In all, more than 80 variations were required and, in order to make a bold visual statement, the client chose a variety of different colours and finishes. Through community and client engagement, a shortlist of five design options was made, with the final design choice being made by the residents themselves.
Performance:
PermaRock’s technical team obtained details of the existing wall construction and calculated that the addition of the PermaRock EPS-Premium EWI system with 90 mm insulation would achieve a U-value of 0.30 W/m2K in line with the project requirements. Dew point calculations indicated that the walls would not suffer from interstitial condensation.
Result:
The scheme delivered impressive enhancements to individual homes and to the wider neighbourhood, improving both the appearance and the energy efficiency of the properties. Energy savings across the four sites were summarised in a REMOURBAN report that was subsequently submitted to Parliament. It noted:
“Total energy consumption savings in Nottingham demo site achieved 41 percent and a total energy use saving of 3GWh/yr, and CO2 (equivalent) saving of approximately 550 tonnes.”
Across the four locations and the five property archetypes, the greatest heat savings were achieved by the properties fitted with PermaRock EWI systems. The calculated annual savings on the properties at Newark Crescent were 10,861 kWh of thermal heat and 763 kWh of electricity.