Retrofit: Low-rise Domestic, Bradford

Project Overview

Background

Incommunities is a not-for-profit housing provider that manages over 22,600 social and affordable homes. Most of these are located in and around Bradford but it also supports properties in Kirklees, Wakefield and Sheffield. It seeks “to provide a diverse range of good quality, warm, and affordable homes while delivering high-quality services that meet the needs of local people.” This includes making them more energy-efficient and cheaper to run.

This £2.9 million project called for decarbonisation measures to be installed to almost 100 occupied properties across two separate estates in Bradford.

Brief

The project was to be funded by Wave 1 of the Social Housing Decarbonisation Fund (SHDF). All works and designs had to meet the requirements of PAS 2030 / 2035. The primary energy efficiency measure would be the installation of an external wall insulation (EWI) system with appropriate enabling works. Other works would include re-roofing and the fitting of replacement doors and windows.

The properties in question were a mix of semi-detached and terraced houses, all of which had previously been rendered. The old material would have to be removed before the new EWI system could be installed.

Design and Specification:

Permarock technical staff assisted the stakeholder team by supporting the property-by-property surveys and retrofit assessments, by carrying out tests on the existing substrates, and by providing visualisations and material samples to assist in the planning process.

As a result of these and other efforts, the team selected an EWI system consisting of Permarock Mineral Fibre insulation and two different Permarock finishes.

System Characteristics

Permarock Mineral Fibre insulation is a non-combustible product that can be used on buildings of any height. It has a thermal conductivity of 0.036 W/mK and is therefore suitable for demanding decarbonisation projects that seek to meet or exceed the Code for Sustainable Homes, BREEAM, Passivhaus and similar standards.

Here, as on many other successful schemes, Permarock SiliconeUltra was applied over the mineral fibre insulation. The combined system enables extremely air-tight facades to be created; an important factor in reducing heat loss from a building. Permarock SiliconeUltra K Finish itself is composed of a silicone emulsion with nano-quartz particles, and it produces a surface that is light, water-repellent and water vapour permeable. For this scheme, a bright white finish was chosen.

In some areas, a traditional dash finish was required in order to preserve the character of certain parts of the estates. For this, the client chose Permarock Dry Dash, which comprises a mineral-cement dashing mortar, covered with pre-washed and screened dashing aggregates of various specified colours. Flexible and self-coloured, the polymer-enriched mortar offers greater durability and performance than traditional sand-and-cement renders.

 

Installation

The scheme was completed on budget in March 2023. All works were undertaken in accordance with the requirements of the SHDF Wave 1 funding and the PAS standards.

 

Result:

The scheme delivered important improvements to the thermal performance of the 96 homes. This has enabled residents to enjoy warmer, more comfortable living conditions and to save on their energy bills.

Client
Incommunities
Specifier
Sustainable Building Services (UK) Ltd
Substrate
Various (Airey & Crosswall Houses)
System
Permarock EPS Premium External Wall Insulation Systems
Finish
Permarock Dry Dash & Permarock Silicone Ultra K 1.5mm