Priority Places for Insulation: Mapping Wales' Home Insulation Needs

Introduction

 Improving the energy efficiency of a home reduces energy bills, improves health outcomes and provides a warmer home for people. With high energy prices and the need to progress net zero ambitions, there has been increased attention on the state of the UK’s housing stock, which is among the oldest and ‘leakiest’ in Europe. Within Wales, a third of cavity walls and eight out of ten solid walls are uninsulated. Even before the dramatic increase in the energy prices, fuel poverty was a considerable concern in Wales with 14% of households estimated to be living in fuel poverty in 2021.

In a bid to improve the energy efficiency of homes and reduce fuel poverty, the Welsh Government will be launching a new Warmer Homes Wales programme later this year. Currently, financial support and advice provision is available through the NEST scheme for households on benefits or other vulnerable households to help them fund energy efficiency improvements.

Although improving Wales’ housing stock is a national challenge, it will be tackled home by home and street by street. The number of homes with poor insulation and household circumstances such as the level of fuel poverty, health and overall age of the population vary between different places. Understanding these differences is crucial for national and local governments to aid decision-making on targeting support and services to the people who need it most. To support this, Which? has pulled together data on a range of factors that determine the need for insulation and created the Priority Places for Insulation Index, which identifies areas likely to be in the most urgent need of insulation.

Methodology

The Priority Places for Insulation Index is a composite index constructed using data from eight different indicators and each has specific metrics of measurement. Five of these indicators focus on the quality of housing stock and are created using data from Energy Performance Certificates (EPCs). These are the average level of all types of wall, loft/roof and floor insulation, average age of local properties and the proportion of properties that are flats. We include age of property in addition to levels of insulation since older properties are likely to be harder to retrofit, while property type matters because flats and apartments need fewer measures to be adequately insulated. 

The three remaining indicators cover household characteristics and comprise socio-demographic and health circumstances of households in a local area. We include income levels as a proxy for fuel poverty, due to data not being available at a local level, as households in fuel poverty will benefit more from having their property insulated. We include the proportion of households aged over 65 because the elderly face worse health consequences from living in a cold home, and similarly we include the incidence of health conditions such as cardiovascular and respiratory diseases as these are worsened by living in a cold home.

The index is constructed individually for each of the four UK nations (England, Wales, Scotland and Northern Ireland) and on three geographical levels. For Wales, these are:

• Lower Super Output Areas, which we refer to as local areas;
• Current Westminster Parliamentary Constituencies; and
• Local Authorities

Further details on the methodology can be found in the technical annex.

Identifying the priority places for insulation

Priority places are local areas which are in the bottom 9th and 10th deciles of the index, meaning they are in most need of insulation. Two-thirds of the priority places in Wales are concentrated in South Wales, with a third in South Wales Central.

Figure 1: Priority places are primarily located in the southern part of Wales

Within South Wales, these priority places are primarily located in the Valleys and major cities.

There are many priority places dotted throughout the towns in the Valleys (Merthyr Tydfil and Rhymney, Blaenau Gwent, Cynon Valley and Rhondda) as shown in Image 1. Since these areas primarily comprise former mining areas, they are characterised by older properties that were constructed with utility and not energy efficiency in mind, resulting in hard-to-treat homes. These former coalfield communities also face challenges related to high levels of deprivation and poorer population health.

Image 1 

Pockets of priority places are also present within cities such as Cardiff, Swansea and Newport, particularly concentrated in the city centres. These clusters of priority places consist of homes with less insulation and are predominantly inhabited by a younger demographic with lower incomes. Encompassing these priority places tend to lie areas of lower priority (see Images 2), which is unlike observed patterns in cities in England and Scotland where the largest cities tend to have relatively low need in the very centre and all cities tend to be characterised by having suburbs that are priority places.

Images 2

Elsewhere, the local level data allows us to identify communities with high levels of need within constituencies and regions that generally have a lower prevalence of priority areas. Looking at the Mid and West Wales region, the majority of the priority places are located towards the inland section of the region, specifically throughout Powys and part of Gwynedd. These communities are largely rural and sparsely populated, with few new housing developments. In some of these areas, although there is a mix of ages, the overall prevalence of health issues is low and the level of fuel poverty is average, suggesting that its residents may not feel the need to urgently insulate their homes. It is not just the rural developments, however, which are high priority. Even in New Towns developed in the 1960s such as Newtown, there are many high priority areas with poorly insulated homes and a significant old population.     

Although only a tenth of priority places are in North Wales, priority places are littered throughout the seaside towns from the North West coasts (Porthmadog, Harlech, and Pwllheli) to Ynys Môn and the Northern coasts of Llandudno and Rhyl (see Image 3). There are many hard-to-treat older properties in these towns due to resort developments in the post-industrial era. These coastal communities also tend to suffer from higher deprivation levels and poorer quality of housing stock, with an ageing population.

Image 3

The index also ranks the need for insulation by constituency. Figure 2 displays the 8 constituencies ranked as having the highest need, along with the indicators that are more dominant in driving the need. Indicators designated as ‘Very High Priority’ mean that the constituency is in the bottom 9th and 10th deciles for that indicator, “High Priority” meaning they are in the bottom 7th and 8th deciles, and so on.

Figure 2: Westminster constituency priority places need heatmap

Supply of insulation installers

Alongside identifying areas most in need of insulation, it is crucial to ensure there is an adequate availability of installers available to service those areas. Using our methodology, we are able to identify installation firms with an online presence and that specify insulation services on the sites that we pulled information from.

The median number of installers in Wales is 17 firms available per 100,000 people, or equivalently, one firm to service 2,262 households which is similar to England. While the lack of installers is a national problem, this is more pronounced in certain constituencies than others. Figure 3 illustrates the relative paucity of firms in more rural constituencies in Mid and West Wales and areas of the North such as Montgomeryshire, Ceredigion, Preseli Pembrokeshire and Dwyfor Meirionnydd.

Figure 3: Supply of insulation installation firms is worse in some constituencies

Combining the data on supply with the need for insulation, we find that five out of the eight priority places have an adequate level of supply compared to the other constituencies in Wales. This suggests that the barriers to obtaining insulation in the priority places are more likely to be consumer-related than a supply chain issue. 

In the retrofit market, certification schemes play an important role in enhancing consumer confidence by ensuring adherence to industry standards and providing methods of redress when issues arise. Therefore, we only categorise suppliers as certified if they are registered with certification schemes that we are confident provide adequate consumer protection. These schemes include TrustMark, Insulation Assurance Authority, and Which? Trusted Traders. 

When considering only certified installers, this reduces the median number of firms in Wales to 14 per 100,000 people, equivalent to one firm per 2,747 households. It suggests that the majority of insulation installation firms in Wales with an online presence are adequately certified.

Conclusion 

Our research reveals that priority places for insulation are distributed throughout Wales, but are more commonly found in South Wales (primarily the Valleys and the city centres of major cities like Cardiff and Swansea). Although there is a lower proportion of priority places in these regions, there are still pockets of priority places throughout Mid and West Wales (inland Powys and in Newtown) and North Wales (many older properties in the seaside towns such as Llandudno and Porthmadog).   

In addition to recognising the need for insulation, the availability of qualified insulation installers is critical in improving the energy efficiency of homes in Wales. Acknowledging the important role of government at all levels in supporting the recruitment and retraining of installers, our research highlights the relatively low levels of installation firms in more rural constituencies. 

We hope that the collation of this data into a single index will prove to be a useful tool for the Welsh Government, policymakers, local governments and others trying to support consumers in improving the energy efficiency of their homes.ex