An investigation of barriers and enablers to energy efficiency retrofitting of social housing in London

Carbon emissions, being hazardous, are triggering social concerns which have led to the housing sector, and draws recommendations to enable effective and efficient retrofitting for social housing projects.


Introduction
Carbon emission emerges as a significant factor that has a dangerous impact on climate change (Solomon et al., 2007). This issue has triggered social concerns that led to the creation of treaties such as the United Nations Framework Convention (1992), Kyoto Protocol (1997, Climate Change Act (2008), the Energy Eff iciency Directive (2012), and Paris Agreement (Change, 2016)these are amongst the few treaties that address the issue of Climate Change. Under the 1997 Kyoto Protocol, the United Kingdom has committed to reducing its carbon emissions by 12.5% over the 1990 levels by 2012 and to achieve a 27% reduction in levels by 2011 (House of Commons, 2016). The initiative by the European Union (EU) includes mandatory carbon reduction targets, the Energy Eff iciency Directive (2012) and the Emissions Trading Scheme. The Climate Change Act (2008) commits the UK to reduce its greenhouse gas emissions by at least 80% over 1990 levels by 2050 (House of Commons, 2016). In addition to this, adoption of the ratification of the Paris agreement (Change, 2016 enables the UK to set a target of net-zero emissions. However, being the oldest member of the EU members (before Brexit), the UK has the oldest housing stock (Davidson et al., 2012). Older dwellings often consume more energy to warm them adequately, compared with more energy-efficient new-built dwellings (Leal Filho et al., 2016). Similarly, Stafford et al (2011), argue that 45% of the UK's carbon emissions are the result of energy-inefficient buildings. In addition to environmental concerns, some other consequences of inefficient energy housing are; public health (physical and mental), social aspects, and fuel poverty which is a significant concern in the UK, with its cold weather and relatively high energy prices. Palmer and Cooper (2013) stated that, in 2011, approximately 10.9% of UK households (2.39 million) were in fuel poverty.
Therefore, a compelling case exists for Energy Efficiency Retrofitting (EER) to domestic buildings in the UK, and especially in the social housing sector. With its high rates of poverty and a higher level of government control over the sector, the national policy can influence retrofitting in social housing more than other forms of tenure. However, initial literature has suggested that the problem of energy efficiency retrofitting in the general building stock has been addressed to some extent whereas little existed on its application to social housing in the UK..
Thus, this paper intends to develop an understanding of energy efficiency retrofitting and common measures reported by the literature as well as the associated barriers and enablers for retrofitting. The paper also brings to light the relevant initiatives and policies set by the UK government, In an and seeks to investigate the barriers and enablers for implementing successful energy efficiency retrofitting in social housing in the London, UK based on the perception of the experts, and making recommendations towards increasing the uptake of such retrofitting.

Social Housing -London
The United Kingdom has the largest stock of social rental housing of about (20%) compared to Spain which merely has 2%. In their study, Arends and García-Almirall (2014) differentiate between the management model of London and Barcelona by focusing on the social and spatial factors to address the housing problem. Therefore, it can be concluded that a relationship between the housing problem, management models, and spatial context exists, and this influences its residents and policies, which is one of the reasons to why this study choses to focus on social housing in London.
Another study by Opoku and Guthrie (2018) argues that the social housing sector experiences an increasing pressure to provide more with less as a result of the UK Government's public debt reduction strategy. This study further explores the delivery of social value in terms of social, economic, environmental impacts in the social housing sector, arguing that organizations often fail to follow the Governmental initiatives and rules imposed, such as the Social value Act (2012) in developing their strategies, policies, and procurement.
Though the government has supported the development of social housing, there has been a substantial decline over the last decade as mentioned by Kleinman (1988). The decline has been uneven, causing differences between the regions and local authorities, where London has been at a disadvantage over the changes in the spatial distribution of lettings. Similarly, Fitzpatrick and Pawson (2007) also reports on the 32 percent decline in the supply of social housing and tenancy turnover for almost seven years until 2004 as seen in Figure 1, which has resulted in added pressure on the allocation system. The Decline in Social Housing and Acceptance of Homelessness Consequently, the limitation to social housing success as argued by Lux and Sunega (2014) is due to the historical and institutional factors such as privatization, informal economy, 'decentralization paradox', and a strong socialist legacy in housing policies.
Therefore, it can be concluded that the government supports social housing by enforcing laws such as the Social Value Act (2012) although there has been a substantial decline in the social housing sector in London due to various factors. Additionally, there exists limited literature that address the problem of energy efficiency retrofitting and its application to social housing in London, which is the main driver behind this research.

Energy Efficiency Retrofitting (EER)
The primary focus of this section is to establish a ground for practical understanding of retrofitting, by considering common measures and governmental initiatives that were considered to aid energy efficiency retrofitting.
According to Eames et al. (2014, p2) retrofitting can be defined as: 'Providing something with a component or feature not fitted during manufacture or adding something that it did not have when first constructed. The term has been used in the built environment to describe substantial physical changes at the building level and has often been used interchangeably with terms such as 'refurbishment,' 'conversion' or 'refit.' This definition is the most accepted definition in the literature, as it provides a comprehensive, clear, and practical understanding of retrofitting, which helps guide this study to investigate Energy efficiency retrofitting and its barriers and enablers. Guided by this definition, this study intends to investigate the most commonly implemented measures of Energy efficiency retrofitting in social housing. In support of this literature reports on a study by Provan and Brady (2015), a sample of 13 housing associations was targeted to investigate the most common measure of energy efficiency retrofitting as shown in Table 1. These were less common and less extensive; older London properties had problems with obtaining planning permission; internal cladding unpopular as loses room space Solar/PV 6 Issues about roof space roofs not facing south, the extent of plumbing needs to be installed. Also, maintenance issues, but some good results, and issues of needing to secure lender consent, even for self-funded schemes.
Air circulations/ ventilation 5 Sources of some problems with tenants in using these Other This includes two with district heating/biomass systems, two with heat pump systems These measures indicate that there has been a positive move towards integrating energyefficient components within social housing. However, there are still certain measures that have not been effectively implemented to enable efficient retrofitting, such as Air circulation measures and Solar/PV, which is an indication of the need for retrofitting in social housing.
In addition to these measures, several studies in the literature report on several government initiatives that have attempted to integrate retrofitting in social housing as described in Table 2. Table 2 Government EER Initiatives

Measure Details
Decent Homes Standard (Urbed, 2016) Intended to improve the condition of social housing. Included modest EE requirements.

EEC replaced by Carbon
Emissions Reduction Target (CERT) (Urbed, 2016) Imposed carbon reduction targets from domestic premises on gas and electricity suppliers.
(Community Energy Saving Programme CESP) introduced (Urbed, 2016) Required electricity and gas companies to deliver EE measures to homes in low-income areas. Promoted 'whole house' approach and high-volume retrofits Phasing Out of Warm Front (Urbed, 2016) Delivered basic insulation and heating improvements to vulnerable households.
A feed-in tariff (Ofgem, 2017) Electricity suppliers must pay for electricity generated by small-scale renewables Energy Companies Obligation (ECO) replaces CERT, CESP and Warm Front (Urbed, 2016) Larger energy suppliers fund the installation of domestic EER measures. Applies to social housing and certain benefits recipients. Low uptake reduced the scheme's impact (Weisselberg, 2015). Intended to complement GD by subsidizing solid wall insulation Green Deal (GD) launched (Urbed, 2016) Lends money for domestic EER, paid back from savings on electricity bills.
Zero carbon homes target and Allowable Solutions Fund scrapped (Urbed, 2016) The Allowable Solutions Fund would have helped retrofit existing housing.

Details
Green Deal Home Improvement Fund closed (Urbed, 2016) The 'Home Improvement Fund' added in June 2014 to kickstart GD. Offered £1,000s in cash, separate from other Green Deal loans, to help domestic EER.
Government ceases funding GD Finance Company (Urbed, 2016) Funding ended due to low take-up and consumer protection concerns. Effectively ended scheme.
Government publishes consultation for changes to ECO in -18 (Urbed, 2016 Changes include a 26% reduction in funding, with focus only on 'affordable warmth' and 'low-cost insulation' Bonfield Report published (Bonfield, 2016) Numerous recommendations to encourage retrofitting, no GD replacement proposed.
Green Deal re-launches using private sector financing (The Green Age, 2017) Additional audits to ensure quality workmanship. Concerns high (c.a. 10%) interest rates and scheme design will discourage uptake.
It is therefore evident from the table above that common measures and governmental initiatives of energy efficiency retrofitting for social housing exist. However, these measures are not integrated effectively due to several barriers and enablers that play a role in effecting the progress of Energy Efficiency Retrofitting in social housing. Therefore, this paper seeks to identify key barriers and enablers for social housing retrofitting as reported by literature.

Energy Efficiency Retrofitting: Barriers and Enablers
Several studies from literature report on a number of barriers and enablers for energy efficiency retrofitting which can be grouped into five categories that include: financial matters, Technical, Government policy and regulation, social factors (including awareness of the energy efficiency agenda), and quality of workmanship (including training for operatives and customer confidence), as presented in Table 3.   (Provan and Brady, 2015) and the 'performance gap' and 'takeback' not as bad as often thought (Webber, Gouldson and Kerr, 2015).

Policy and Regulation
• Strong mandatory national policies (Eames et al. 2014). • Lack of replacement for the Green Deal, Chopping and changing regulations and schemes, Policy vacuumlittle Government attention to energy efficiency matters and Right to buy makes retrofitting more (Weisselberg, 2015).
• Government creating greater access to finance (Bonfield, 2016); • Increasing the cost of inaction and helping spread investment cost (Stafford, Gorse and Shao, 2011

Quality and customer confidence
• Lack of confidence in suppliers (Webber et al. 2015); • Shortage of skills to carry out retrofit works (Vaughan, 2017); • Insufficient information on techniques and best practice for suppliers (Eames et al., 2016); • Loss of knowledge and skills between projects (Stafford, Gorse and Shao, 2011  It therefore seems apparent from the table above that there are no studies that report on the barriers and enablers of the financial, technical, regulatory, social, and quality categories in relation to UK social housing. Accordingly, this paper intends to seek stakeholder's views of the barrier and enablers within the context of London, UK social housing.

Methodological Steps
A qualitative approach based on semi-structured interviews and survey was used to identify the barriers and enablers for social housing retrofitting from the key stakeholders' point of view. The following methodological steps were therefore followed: • Interviews: A set of interviews were conducted to understand stakeholder's view of the barriers and enablers of energy efficiency retrofitting in social housing , targeting a sample of 7 key London based professionals including; employed as sustainability consultant, development manager, and investment planning officer in companies like National consultancy, local authority, housing associations, and construction repairs & maintenance contractors • Ranking Survey: Experts/professionals as such; consultants, contractors, large and small housing associations and local authorities were asked to rank the categories based on their perception. This approach is intended to corroborate and triangulate the findings from the literature and the interviews against the perception of Energy Efficiency Retrofitting for Social Housing experts based on the ranking generated by the survey.
These methodological steps will assist with developing an understanding of the stakeholder's perceptions of the barriers and enablers to energy efficiency retrofitting of social housing in London.

Data collection and analysis
This section explains how the methodology outlined above was put into practice to develop an understanding of Energy Efficiency Retrofitting challenges facing Social Housing from the perspective of key professionals.

INTERVIEWS
The semi-structured interviews assist the research in determining the barriers and enablers for each category, from the key professionals' perspective.

Profile of interviewees
The table below shows a summary of the interviewees' profiles, where 3 of the interviewees worked in National consultancies, 2 for a housing association, and others at the local authority. The interviewees mostly worked as sustainability managers or project managers with experiences ranging between 6 to 16 years, while being between at least 2 to 6 years in their current post.

BARRIERS AND ENABLERS
Several studies from literature report on grouping the barriers and enablers into five most significant categories as shown in Table 3; however, the interviewees perceived IT and Disruption to residents as significant standalone categories, which resulted in identifying seven Peel, Ahmed, and Saboor Construction Economics and Building, Vol. 20, No. 2, June 2020 main categories. This section, therefore, presents the interviewee's perceptions of the barriers and enablers for each of these categories, which include: financial matters, Technical, I.T, Government policy and regulation, social factors (including awareness of the energy efficiency agenda), quality of workmanship (including training for operatives and customer confidence) and other factors, as discussed below:

Financial
The interview results showed that 'Financial' issues are the biggest barrier. For example, interviewee A argued that "The major barrier is definitely financial, and also again concerns about contractors' workmanship and quality of design and specification as well." The rest of the interviewee's comments are summarised in Table 5a, highlighting the financial issues as barriers and enablers for retrofitting energy-efficient components in social housing. Therefore, it can be concluded from Table 5a, that from the perception of key professionals, 1% rent cut, financial situations of SLs, low level of grant funding and split incentives between SLs and residents/leaseholders were considered as the most important barriers.

TECHNICAL
Some of the most highlighted technical issues of EERSH found from the interviews are the need for individual design, poor workmanship, and performance gap as described by Interviewee A: "Definitely poor workmanship that would be one thing. Poor selection of products and in the worst cases not installing the specified products.". Similarly, Interviewee E mentioned: "I would say there are probably three elements you would look at. One aspect you would look at designs…. So, I would say design and client understanding is a really big one. On the back of that is budget …, so behavioural change is quite a difficult one, particularly in social housing. And maintenance is another one." The rest of the interviewee's comments are summarised in Table  5b, highlighting the technical issues considered as barriers and enablers for retrofitting energyefficient components in social housing.  The rest of the interviewee's comments are summarised in Table 5c.  The rest of the interviewee's comments are summarised in Table 5d, highlighting the 'government policy' and 'regulation issues' considered as barriers and enablers for retrofitting energy-efficient components in social housing. There is no longer trust in Government schemes after the repeated changes to ones such as ECO, GD, FIT, etc. which were major funding streams for EER. The changes prevent contractors from upskilling and investment in the supply chain. The start-stop nature of Government schemes and the difficulties caused by SLs having leaseholders under the right to buy was ranked as the most important of these factors.

Social Factors and awareness of energy efficiency
Interviewee B highlighted the resistance and concerns related to energy efficiency retrofitting by stating "Generally people welcome it as a good thing, but you know, it depends on the measure, it depends on the context, you will have, you might have a block with 20 residents, who look at doing (solid wall insulation?), you know 18 residents will be quite happy that they are, you know, the block is being given a new façade, you know, a new look, but you will have a couple of residents who just don't want the work because they may not want the disruption ….., it is a mixed picture.". However, regarding the concern and demand of residents for energy-efficient retrofitting Interviewee D stated: "I think they are interested, but they don't bombard me with requests and calls for support …. if they are struggling to pay their bills. They are always interested to learn ways in which they could help themselves reduce their bills etc." Table 5d continued An investigation of barriers and enablers to energy efficiency retrofitting of social housing in London The rest of the interviewee's comments are summarised in Table 5e, highlighting the 'Social factor' and 'awareness issues' considered as barriers and enablers for retrofitting energy-efficient components in social housing. The balance of concern for fuel poverty vs. carbon reduction Three interviewees thought fuel poverty was a major concern. Another thought the balance changes at different times, with another saying they were an equal concern. One interviewee thought they could not be addressed separately, and another thought they can conflict.
Barrier 4 Lack of concern from SLs Fabric is a higher priority; EE is 'nice to have' not essential, a lack of awareness of the benefits to SLs of EE works Barrier 3 Low social and national concern re EE Not taken seriously at the national level and awareness has gone down recently Barrier 2 Low levels of concern and awareness amongst SLs leaseholders Barrier 2 Resistance to works by residents Some fear central heating will be more expensive to run or do not like changes to buildings' appearances.

Enabler 6 Concern from SLs
There is plenty of concern regarding EE, especially in terms of fuel poverty, lots of discussion of EE, having board-level buy-in and general concern is an enabler. Some SLs have targets.

Quality and Customers confidence
Issues related to quality and customers' confidence for energy efficiency retrofitting for social housing can be witnessed through the statement of Interviewee E "I would say it is just as bad. Probably 2 years ago, because of the Green Deal, everyone thought it was something to get into, so you got a rush of trained people. Whether or not they are of particularly good quality is difficult, but in theory that is what the PAS 2030 was supposed to help with, but certainly before and now, a lot of the companies have gone out of business, so there is a lot smaller market it is probably better than the building industry as a whole, because it was so specialized, for a little while, and there is obviously not as many projects coming up.". The rest of the interviewee's comments are summarised in Table 5f, highlighting the 'quality' and 'customer confidence' issues considered as barriers and enablers for retrofitting energy. Lack of staff, resources, and skills to effectively monitor works is a barrier. Two interviewees mentioned the overall lack of people with skills in EE and contract administration. One contractor state that the project is 'as good as the client.' One interviewee disagreed and believed SLs do have the skills needed.

Enabler 4 Availability of competent contractors
This split opinion -four interviewees thought there were sufficient, whereas two thought there is a problem. The need for due diligence to avoid problems was raised by two interviewees.

Other Factors
In addition to the above-mentioned categories that have been mentioned by the literature, the interviewee mentioned other factors that form barriers to energy efficiency retrofitting, which include 'disruption to residents' and 'concerns raised by Grenfell Tower fire'. Has discouraged retrofitting and led to cancellation/suspension of some projects. Interviewees expressed views such as the need for improved communication with residents, reviews of Building Regulations, and trust-building with the public to overcome such problems.
Moreover, to improve the reliability of the findings gained through interviews, a ranking survey was constructed to aid corroborating and triangulating the opinions of energy efficiency retrofitting experts. The survey also determines the most significant issues already identified from literature and interviews, which will be discussed in the next section.

RANKING SURVEY
To understand the relative importance of the categories of barriers and enablers found from the literature and validated through semi-structured interviews, professionals were asked to rank these categories. For ease of interpretation, the ranking of the categories has been displayed graphically in Figure 2.  Weighted average rankings for survey data the categories of barriers and enablers Furthermore, for a better understanding of the data collection and analysis phase, a corroborated and triangulated analysis are summarised in Table 6. The table summarises the ranking survey's results, linking categories' ranks with the three most important ranking factors in each category. This provides a useful summary from which conclusion can be drawn. 3.14 Therefore, the most prominent findings that have been identified in relation to energy efficiency retrofitting are summarised below: • Issues of finance, technical difficulties, and issues of government policy and regulation are considered the most significant barriers and enablers to EERSH. • The low level of social concern for environmental and EE issues is a barrier to EERSH and the wider EE agenda. • Government policy, while being deficient in many areas, has had considerable success in encouraging EERSH, notably through ECO and its predecessors, CERT and CESP and the Decent Homes Initiative. • Government support and attention in terms of compulsory national targets for EERSH, potentially mirroring EE(PRP)R 2015, would drive change and are looked upon favourably by EERSH professionals. • Repeated changes in Government policies, especially reduction/removal of promised funding streams (ECO, GD, FIT), have eroded trust and hampered development in the supply chain. • Low levels of grant funding, including reductions to ECO, are regarded by most professionals in the field as a significant barrier to EERSH. • The 1% rent cut is having a significant impact on SLs business plans, complicating their ability to carry out EERSH. • Hard to treat properties are a significant barrier. This is an increasing problem as the 'low hanging fruit' of easy to treat properties are upgraded. • Overall, there is not a great concern at the availability of competent contractors or the ability of SLs to manage works; however, continuing development is needed. • The availability of good quality stock condition and SAP data is critical for SLs to target investment.

Conclusion
This paper has developed an understanding of retrofitting for social housing and its common measures. Government initiatives that integrate energy efficiency retrofitting in social housing have also been reported from literature, which showed that despite the numerous efforts and initiatives that have been taken, there still seems to be a lack of energy-efficient retrofitting in social housing in the UK. This paper has, therefore, targeted key stakeholders from the social housing industry to get a deeper insight into the barriers and enablers for retrofitting in the sector. The study concluded that 'financial' and 'government policy' barriers were the greatest barriers facing retrofitting for social housing.
Based on the above findings, the following recommendations can be made for key stakeholders within the Social Housing sector, to enable a more efficient and effective retrofitting.
• Introduction of legally binding national EE targets for the SH sector. • Much greater stability in Government policies and funding. • More grant funding for EE works.
• Developing better and more innovative ways of funding and retrofitting hard to treat properties, especially ones with solid walls. • Research into innovative solutions for hard to treat properties. • Research into the financial benefits to SLs of implementing EER to help make the business case for internal funds.
Although the problem of energy efficiency retrofitting in social housing has been addressed to some extent by this scoping study, future research intends to focus on a wider sample of stakeholders across the UK with more sophisticated data analysis techniques such as Delphi and Analytical hierarchy process (AHP), to increase the reliability and validity of the results and aid the stakeholders (decision-makers) to prioritize their efforts to overcome the barriers highlighted by this study.