**2.1 The drivers of adaptive reuse of listed churches**

In Europe, many religious heritages are under threat and the buildings are often ill adapted to the needs of modern society [22]. This is because a lot of these buildings are reaching the end of their useful life and in most cases do not respond well to contemporary needs. As a result, they are often less desirable to occupy, can remain empty and ultimately deteriorate. In England, three quarters of 16,000 parish churches of England are listed as buildings of architectural and historic interest. The churches listed Grade I comprises about 45% of all England's buildings (i.e. Castles, mansions, banks, railway stations, etc.). However, with the declining congregational sizes, a number of these buildings are becoming less used and closed for worship (**Table 1**). Thus, one of the drivers for retrofitting of heritage buildings is redundancy.

It can be seen from **Table 1** that from 1969 to 2014, over a thousand church buildings have been closed and considered for alternative use. Perhaps, this is as a result of historical factors such as population shifts, changes in religious practice and habits, or even the construction of new buildings for religious use. According to [24], redundant buildings are buildings that have reached the end of their original working lives, but often have huge potential to be adapted to economically viable new uses. It should be recalled that one of the Council of Europe's statutory duty is to safeguard the ideals and principles of the common heritage of member states and to which religious buildings bear witness ([25], p. 1). This brings to fore religious buildings' importance in terms of their architectural and historical


#### **Table 1.**

*The future of closed church buildings since (1969–2014).* 

significance and their longstanding concern for the integrated conservation to ensure a future for the past. In the UK, heritage buildings such as churches and farm buildings are being reused. Meanwhile, due to their population (**Figure 1**) more listed churches are converted to alternative use and/or demolished.

 When a religious building is no longer viable; efforts should be made to ensure a future use, whether religious or cultural, as far as possible. However, this should be compatible with the original intention of its construction and as such should be carried out with the understanding that a church or any other major religious building is often the focal point and central feature of a community and a local landmark. While there are numerous successful examples throughout Europe of the preservation and protection of redundant religious buildings, through their sensitive adaptation to new uses, thus this paper poses a challenge to responsible stakeholders (e.g. churches, government, local authorities and heritage building professionals) and other heritage building experts to (i) consider effective measures to preserve redundant religious buildings and secure wherever possible their appropriate future use; (ii) promote projects for reuse and re-adaptation not incompatible with the original function of the building and do not cause irreversible alteration to the original fabric; (iii) encourage a more imaginative use of existing religious buildings as well as (iv) encourage the research necessary for the continuous upkeep of religious buildings. This challenge provided the motivation behind this research and action required to implement strategies aimed at promoting energy efficiency and limiting energy consumption as a fundamental aspect of reuse of built heritage. Thus, informed by the aforementioned challenge, this paper seeks to investigate current retrofitting strategies and interventions in the reuse of heritage buildings with a view to assess the current performance of LCBs through the viewpoint of energy efficiency.

The adaptive reuse of church buildings becomes significant in conservation fostered by the economic benefits associated with tourism they could generate

#### **Figure 1.**

*Post war listed building types in England. Source: Author's survey [30].* 

*Improving Environmental Sustainability in Reuse of Some of England's Churches: Challenges… DOI: http://dx.doi.org/10.5772/intechopen.81222* 

 [26, 27]. However, retrofitting of these buildings is faced with the challenges of meeting the global challenge of coping with climate change. A major challenge for heritage buildings is how they can successfully be rehabilitated and made energy efficient at a time that the need for their renovation and re-use appears to be urgent and make them fit for the twenty-first century. "In Europe, the legislation concerning this area is based on the certification of energy efficiency, developed in the early 1990s as a primary strategy to reduce energy use and carbon emissions as well as the energy policy adopted in 2007, called Horizon 20-20-20" ([28], pp. 1294; [29], pp. 1493–1502). However, low energy use as a key contemporary demand for better standards of living and as a response to climate change has not yet been extended to the retrofitting of LCBs. The scale of the problem is exacerbated by the fact that churches are difficult to modify to meet up with current energy efficiency standard. Nonetheless, users of rehabilitated church buildings also need to have healthy and thermally comfortable internal environments at an affordable installation and running cost. The problem is that certain restrictions deriving from the specific historic character do not permit major interventions to improve the building's energy performance. Indeed, when dealing with protected buildings of significant architectural merit, altering the building envelope will be prohibited. This difficulty is partly due to the nature of the materials from which they were built as traditional buildings; which affects their thermal performance in terms of heat loss requiring significant updating.

 LCBs continue to present a retrofit dilemma all of their own. For instance, the fabric of heritage buildings functions in a certain way due to the way they were built. Thus, makes it challenging to improve their fabric thermal performance. However, to avoid degradation of their fabric they should be preserved because of their breathable elements. Thus, a clearer understanding of their values and needs must be found so that an appropriate intervention can be adopted. Specifically, the challenges of rehabilitating Heritage buildings could be attributed to several factors such as heritage factors, embodied energy, economic factors and building factors (**Figure 2**).

In addition, it is difficult to understand their current energy performance. LCBs traditionally have solid walls, meaning they are 'hard to treat buildings' and hard to

#### **Figure 2.**

*The drivers and the challenges of retrofitting and environmental sustainability of heritage buildings. Source: Akande [30].* 

deal with when alterations are locally permitted. If the fabric of the building cannot be readily improved, the question that this study seeks to answer is what options are available to reduce the energy consumption of Heritage buildings with specific reference to investigate operational energy performance involving existing adaptive reuse of LCB projects. Thus, this paper's aim is to investigate current retrofitting strategies and interventions in heritage buildings. The objective is to assess current performance of the existing reuse of heritage buildings through the viewpoint of energy efficiency.
