• Project name: Dykehead Road, Airdrie
• Lead organisation: North Lanarkshire Council

Statement of support

North Lanarkshire Council has an ambitious New Supply Programme, which aims to provide 5,000 new council homes by 2035. Dykehead Road in Airdrie is a new build housing project which has delivered 150 homes towards this target. 19 of these 150 homes have been constructed with enhanced sustainability technologies such as: 

• Additional solar panels to assist with reducing running costs for the home and reducing demand on the national grid
• The installation of battery storage units which store the electricity generated from the solar panels when not being used
• The installation of highly energy efficient air source heat pumps which will allow the tenant to heat their home without the use of gas or any other carbon sources
• Enhanced insulation to minimise heat loss
• Enhanced triple glazing windows and doors specifications to further minimise heat loss.

One of the aims of this project is to investigate the benefits of alternative heating sources, solar energy generation and battery storage to help inform future decision making and help achieve North Lanarkshire Council’s climate targets and reduce fuel poverty for tenants.

The air source heat pumps fitted to each property have the potential to result in CO2 savings of around 2,000kg per year per property. This is even more notable when it is combined with 4kw solar photovoltaic panels which can result in an additional 1.32 tonnes reduction annually, on average.

Almost a quarter (24 per cent) of dwellings in North Lanarkshire are classed as fuel poor. This increases significantly to 36 per cent within North Lanarkshire’s social rented tenured dwellings. The main causes of fuel poverty, according to Energy Action Scotland, is poor energy efficiency, low disposable household income and the high price of domestic fuel. This project has the potential to achieve a positive impact on each of these drivers. The associated feasibility study for this project estimates that air source heat pumps could save tenants around £105 per year compared to a traditional gas combi boiler. Tenants could also see further savings of between £90-£220 per year due to the 4kw solar photo voltaic provisions. This would equate to total savings of between £195 and £325 per year. Wider societal benefits also include a reduction on pressure on the national grid due to solar photo voltaic and battery storage used to power the air source heat pumps.

Dykehead Road tenants also benefit from the installation of electric vehicle charging points to support the use of hybrid or fully electric vehicles. Another feature of the development aimed at reducing carbon emissions are the sustainable active travel links, facilities for walking, cycling, wheeling and access to public transport in the area. The properties are also provided with data cabling throughout to enable easier home-working and less reliance on having to travel to work. The average EPC rating of this development is A (92+).

North Lanarkshire Council have been engaging with tenants in the 19 enhanced sustainability properties to monitor energy usage and convey monetary savings for the residents. This work has been undertaken by recording meter readings, examining fuel bills and using mobile apps to measure the data from the respective air source heat pumps and battery storage technologies. Early signs indicate that in comparison with a gas boiler heated property, energy bills have reduced significantly with savings of between £50-£100p/m depending on individual usage. 

Success in reducing carbon emissions will assist with decarbonisation without increasing energy fuel bills. The homes will be robust to protect against longer-term climate change due to enhanced building specifications and cooling requirements in a potentially future warmer climate.

Outcomes and achievements

North Lanarkshire Council have delivered 150 homes for affordable social rent which completed in February 2024. This has reduced the pressure on the common housing register and has an indirect benefit of freeing up more council homes as most of the 150 new tenants have moved to Dykehead Road from other council properties.

The development was part funded by the Scottish government More Homes Division – with additional funding for new net zero technologies to encourage innovation of technology and design. The financial support focuses on low carbon heat generation solutions and measures to support the decarbonisation of heat in Scotland.  

As part of a planning condition for this site, a commuted sum of £300,000 was directed to the local leisure centre which has used this money towards the upgrade and installation of a new 11-a-side football pitch, which was completed at the beginning of 2023.

A monitoring and data collection exercise of the energy efficiency of the new homes is currently in the latter stages of being fully complete. Once finished, we hope to be able to share the results widely with our partners including the Scottish government and other local authorities, as promised during the grant funding application.

• Project name: Net Zero Catalyst
• Lead organisation: Wheatley Group

Statement of support

Wheatley Group is actively meeting the challenges of net zero in our retrofit plans as a means not only to address carbon emissions but also in a way that fundamentally mitigates fuel poverty and prioritises local skills and labour. We’re investing across the whole geography of the group and throughout the variety of property types - utilising a range of solutions; all towards making homes more affordable for all our customers.

We estimate that heating our homes produces around 150,000 tonnes of CO2 each year. This is based on typical energy consumption in UK properties and the heating systems used in our homes. Through Your Homes, Your Community, Your Future, we committed to reducing these emissions through our investment in energy efficiency measures.

To achieve this we’re implementing various net zero deep-retrofit projects which combine multiple measures as a single solution. Spanning various property types and localities ranging from dense urban Glasgow ‘non-trad’ Canadian timber through to brick bungalows in the Galloway forest. We’ve worked with our supply chain partners to overcome many technical and logistical complexities. This work is bringing properties at EPC ‘E’ up to EPC ‘A’ in one jump. Combining building fabric whole house improvements, renewable electricity generation, zero emissions heating and customer support solutions which as a collective have been shown to remove not only the carbon emissions from hundreds of homes but in many cases remove over 60 per cent of the cost to operate too.

In terms of the focus projects, in the past year we’ve installed 362 ASHP to replace oil burners, defunct electric storage and even some coal heating, providing around 2,413kg CO2e saving per property and an estimated average cost saving of £987 per home per year. Electricity needed to operate heating will is being generated by installing an average 4kWp solar PV array and 9.5kW battery storage capacity. By installing a high efficiency whole-house insulation approach comprised of rigid EWI insulation board to achieve a target wall U-value below 0.29W/m2/K, loft insulation to 0.11W/m2/K, and underfloor insulation wherever achievable, plus new high specification windows and door. Space Heating consumption has reduced to 70kWh/m2/yr or below, well in excess of forthcoming targets.

Within the current programme another 123 properties are being worked on as this ‘catalyst’ approach gathers pace. Hearing from tenants has been crucial to emphasise that the approach is working. For example Jamie Sneddon, from Upper Nithsdale in Dumfries and Galloway, had the whole house net zero specification upgrade work and said:

• “I think the battery is amazing. I love it and I am really seeing a difference with my energy bills. I really can’t believe how cheap the energy is through this system. When I first moved in the bills were really high with the storage heating and now I’m seeing such a difference”.

Reducing emissions are a key focus, although the solutions we’re implementing have yielded significant knowledge and new processes to enable this work to increase pace whilst reducing costs. We’ve created a set of design and implementation requirements that are very detailed and replicable; taking some of the vagaries out of design which too often has stymied the benefits that should have accrued to customers.

We’re not stopping here as Wheatley Group’s Sustainability Framework plans to replicate this work.

Outcomes and achievements

We have completed 362 new zero whole-house deep retrofits to date, including full external wall insulation, double glazing, solar PV arrays, battery storage backup, loft insulation and zero emissions heating upgrade along with associated distribution and emitters.

To enable this we’ve worked with SPEN to deliver infrastructure upgrades, as well as arranging smart meter changes and flexible tariff switching for customers.

We’ve prioritised local supply and delivery partners, which is specifically important in rural and remote rural areas of Dumfries and Galloway.

In terms of carbon outcomes, based on the transition from oil burner systems to ASHP with accompanying PV generation, we estimate around 2,413kg CO2e saving per property and an estimated average cost saving of £987 per home per year. Therefore a cumulative saving of 873 tonnes of CO2 per year and over £357,000 in the pockets of customers whom otherwise would have continued to struggle with the high cost of fossil fuel heating.

• Project name: Dundashill
• Lead organisation: West of Scotland Housing Association

Statement of support

In spring 2024 West of Scotland Housing association completed Dundashill Plot 3 - the first plot development of the Dundashill regeneration masterplan and one of several that will form part of a new low-carbon, mixed-use community constructed upon the former site of the Diageo Distillery in north Glasgow. Sustainability was a key consideration throughout the design and build process of Plot 3, demonstrating bold new ambitions in energy-efficient home building for social landlords, considering both Scope 1 and Scope 2 carbon emissions for the new site compared to similar past projects.

The homes have been entirely constructed using an advanced version of the CCG iQ Timber System. Manufactured offsite using sustainably sourced timber under zero-waste conditions just 11.7 miles away, the closed panel nature of iQ is advantageous to the creation of Passivhaus homes. Not only do they require to be super-insulated, airtightness is further maximised by sealing all draft zones through the use specialised tape and the introduction of Passivhaus-accredited, UPVC recycled triple-glazed window and enhanced door sets, also manufactured locally, to create a thermal bridge-free construction. Once on site, CCG’s site team carefully assembled components for the entire building envelope to ensure that heat loss was minimised with the residual economic benefit of vastly lower fuel bills for the end user [EPC range from 85 (B) to 94 (A)].

The improved fabric is augmented by solar PV panels that connect directly to the property while the wider lowering of emissions is undertaken using a heat pump water heater for each plot rather than a gas boiler. MVHR is also used to deliver clean warm air flow throughout each dwelling.

The composition of Plot 3 has developed to sit within the confluence of the existing community as well as the neighbouring plots under construction. Each plot is interconnected by pedestrian and cycle routes to encourage active travel, a complementary feature to the inherent low-carbon nature of the development itself.

An Electric Car Club provider has been assigned to the site and a car club will be initiated once 20 residents register.

Each flat has been designed to be flexible and easily reconfigured and dissembled to adapt to tenants’ changing needs.

Our PH assessor will be monitoring the impact on PH standard to understand if it is performing as we expect and see if we can improve on the information and guidance given to tenants to maximise the benefits and minimise energy demand. 

To do this we will be measuring tenants’ energy consumption and the temperature within your home over the next two years. Environmental Loggers will be installed to around 25 per cent of tenant’s flats and a questionnaire will be completed each autumn. The sample will include flats with the Ariston ASHP and the McDonald Cylinder direct electric boiler so that we can understand the difference in the electricity consumption between the two. Similar family compositions have been selected to compare like for like and to identify those who achieving better performance results for the association to learn and develop good practice.

Tenant quotes:

•  “The area is so quiet, and my neighbours are lovely. The views over the city are spectacular. I am delighted that there will soon be a car sharing club. My energy bills are only £41 per month, this is over £150 more that my energy bill from my last home. This extra income has really helped with the cost of living increases.”
• “I absolutely love living in this home, it is warm and have hardly put any heating on since February. My energy bills are really low, massive difference from my previous tenement flat which was expensive to heat.”

Outcomes and achievements

The key outcomes and achievements for the project are:

• Highly energy efficient homes resulting in low energy bills thereby tackling fuel poverty
• High satisfaction rates from tenants
• 70 per cent of design off-site
• Excellent levels of thermal comfort
• 80 per cent of PVC windows were made from recycle materials
• Each flat internally lends itself to dissemble thereby creating flexibility to carrying out adaptations
• Homes were manufactured offsite using sustainably sourced timber under zero-waste conditions, less transport and construction period resulting in lower emissions
• Low carbon heating and hot water systems
• Monitoring systems in place to capture data from residents to monitor the buildings performance and develop/share best practice
• Rain gardens with high ecological plants to maximise biodiversity benefits.

• Project name: The EnerPHit Standard Project
• Lead organisation: Cairn Housing Group
• Partner organisations: Changeworks, John Gilbert Architects, GMR Henderson

Statement of support

The social housing sector is under significant pressure to meet statutory targets for energy efficiency, net zero carbon, and reduction of fuel poverty. The challenge is particularly acute when addressing existing housing stock, especially properties of non-traditional construction or those built over forty years ago. These buildings often present unique obstacles; not just in physical structure but in energy performance, which frequently falls short of modern standards.

One issue is the performance gap between predicted outcomes from Energy Performance Certificates (EPC) and the actual performance of a building. This can lead to substantial investments in energy efficiency measures yielding minimal returns for tenants. Sometimes measures can harm the building, introducing issues such as mould, damp, and poor air quality.

To address these challenges, Cairn implemented the EnerPHit standard on two adjoining post-war houses in Wick. EnerPHit is a rigorous retrofit variant of the Passivhaus standard with shared core principles, including meticulous design to ensure air tightness, elimination of thermal bridging, high insulation levels, and maintenance of excellent indoor air quality. When combined with renewable heating solutions, the EnerPHit standard minimises the performance gap, ensuring tenants benefit from significantly lower fuel costs and healthier living environments.

This project was a pilot study to assess feasibility, costs, and practical implications of applying the EnerPHit standard to existing housing stock. It also aimed to explore impact on fuel poverty and to derive lessons that could inform Cairn’s strategy for meeting the Social Housing Net Zero Standard. The broader goal being to develop a scalable model that enhances energy efficiency across the portfolio and helps eradicate fuel poverty among tenants.

Wick was chosen due to its high levels of fuel poverty and socio-economic challenges. With support from Changeworks, Cairn secured funding from the Scottish government's Social Housing Net Zero Heat Fund. John Gilbert Architects were appointed as architectural consultants, delivering the Passivhaus Planning Package model and full drawing packages, including EnerPHit certification. Local to Caithness, GMR Henderson took on the role of principal contractor.

The results are remarkable. Both homes have been transformed with highest levels of insulation, effectively rendering traditional central heating unnecessary. EPC ratings have soared from F to A, and air permeability has reduced from 20m³/h/m² @50Pa to below 1 m³/h/m² @50Pa.

The significant improvement in energy efficiency not only helps tenants combat the climate crisis but alleviates fuel poverty by significantly reducing energy costs. This project marks an essential step in supporting the Scottish government’s Net Zero transition plan, particularly in rural areas where developing local supply chains is critical.

Achieving EnerPHit was not without its challenges: rising material costs, lack of local specialist contractors, supply chain issues and retrofitting to this standard is more complex than new builds due to intricate thermal and airtightness strategies required.

The dedication and willingness of all involved to learn and innovate were crucial to the project's success. Today, both houses are certified Passivhaus EnerPHit, making Cairn the first registered social landlord (RSL) in Scotland to achieve this status.

Moving forward, while this pilot proved successful, it was recognised as too onerous and costly to replicate and adopt as the standard. Cairn is working to use gained insights to develop more cost-effective retrofit solutions that maintain high performance and energy efficiency, without the stringent requirements of EnerPHit. Future retrofits will be designed with a more pragmatic approach; balancing practicality, buildability, maintenance, moisture risk, health, and cost. Cairn is currently applying this approach to two neighbouring homes to allow comparison. The project has informed wider component specifications to ensure that energy demand can be reduced even when ‘standard’ component replacement is taking place.

Outcomes and achievements

The EnerPHit retrofit of two post-war houses in Wick delivered transformative outcomes, both in terms of energy efficiency and tenant wellbeing. These homes have been elevated from an EPC rating of F to A, and their air permeability has been reduced from 20m³/h/m² @50Pa to below 1 m³/h/m² @50Pa. This dramatic improvement in thermal performance has rendered traditional central heating systems unnecessary, significantly lowering both energy consumption and carbon emissions.

The project also addressed fuel poverty, as tenants of these homes have reported they now benefit from substantially reduced energy bills, along with a healthier living environment characterised by better air quality and consistent indoor temperatures.

As the first RSL in Scotland to achieve Passivhaus EnerPHit certification, Cairn has set a benchmark for future retrofits within the social housing sector. Moreover, the project has highlighted critical challenges, such as skills shortages and supply chain issues in rural areas, providing invaluable insights that will shape more cost-effective and scalable retrofit strategies in the future.

This initiative not only supports the Scottish government’s Net Zero ambitions but also strengthens local capacity and gives the opportunity for them to deliver and manufacture high-performance housing in rural communities.