Each volume of Journal of Building Survey, Appraisal & Valuation consists of four 100-page issues in both print and online.
The articles published in Volume 12 are listed below.
Volume 12 Number 4
Traditional buildings have a central role to play in Europe’s plans to be the first climate-neutral continent by 2050, with the building sector being the single largest energy consumer in the EU with 40 per cent of total energy use. Seventy-five per cent of the existing housing stock is energy inefficient with minute numbers renovated each year. Existing buildings offer huge potential for energy use reduction. Research has shown that a historic retrofit can emit less carbon compared to demolishment and rebuilding. Reductions in carbon emissions of up to 62 per cent were observed across a body of case studies by Historic England, including a 95 per cent reduction in the mews case study described in this paper. Moreover, carefully managed thermal retrofits, taking a ‘whole house approach’, have many benefits, including improved indoor comfort and air quality as well as reduced operational costs. These are factors which are fundamental in ensuring the continued use of historic constructions while improving their standards of preservation and durability. Thermally upgrading traditional building is still a much-debated topic. Inappropriate thermal interventions with unsuitable materials and finishes can have unforeseen consequences, resulting in building damage and a reduction in internal comfort, health and well-being. This paper aims to contribute to this discussion by providing an overview of key considerations when thermally upgrading the walls of traditional buildings while preserving unique characteristics and functionality. Advantages of adopting thermal mortars such as cork lime are put forward, and their potential efficacy is discussed, concluding with a case study focusing on the deep retrofit of a London mews within a conservation area.
Keywords: thermal mortars; lime; thermal retrofit; plasters; energy efficiency; heritage; historic; climate change; traditional buildings
This paper is about water damage in buildings and the resulting mould infestation, its causes, detection, identification, remediation and health Implications. The author believes based on science, practical experience and successful case studies over the last 37 years that by proper understanding of the causes, much misdiagnosis, misidentification and mistreatment can be avoided, and correct testing, identification and enumeration of the moulds is the vital key to successful remediation measures. All moulds are not equally destructive, toxic or pathogenic. It is important to determine the type and extent of both visible and non-visible mould and hidden moulds in floor voids, wall voids and other confined spaces.
Keywords: water damage and mould; causes of mould; moulds and health Implications; detection of mould; hidden moulds; mould remediation
The Energy Performance of Buildings Directive (EPBD) is the European Union’s main policy instrument for reducing the built environment’s contribution to climate change. Energy Performance Certificates (EPC) are a tool of this policy, providing buildings with a performance rating. In the UK these have become the benchmark by which the Minimum Energy Efficiency Standards (MEES) are judged, rendering residences lower than an E illegal to rent out. This has pushed property owners to undertake energy retrofitting interventions to ensure compliance. In traditional buildings this is potentially problematic. Buildings of this type rely on permeability to control moisture dynamics; the insertion of less permeable barriers can interrupt their internal hygrometry leading to condensation, damp and decay. As a result, subsequent damage to the building fabric can bring energy policy into conflict with heritage conservation. Existing frameworks that attempt to mitigate the tension within these agendas often fall short in explicitly considering the the problem holistically. This research first asks if pressure from policy is leading to incompatible retrofits. Secondly, it aims to develop a holistic framework that unites heritage and energy agendas with current policy. An inductive, pragmatic approach was undertaken. Using a historic estate’s residential portfolio as a case study, condition surveys were carried out to assess whether properties retrofitted with secondary glazing were experiencing problems with condensation. The results of this were significant, supporting the argument that energy policy is driving incompatible retrofitting interventions. Exploratory data analysis was carried out on an existing EPC dataset to highlight inconsistencies with the EPC methodology. Finally, these findings were combined with questionnaire survey results, targeted at both professionals and occupants, to inform a decision-making framework that incorporated energy efficiency, heritage values, life cycle cost analysis (LCC), building assessment, occupant behaviour, with a feedback loop promoting a bottom-up approach to policy. This issue contains Part 2 which will deal with the methodology and results. Part 1 in the previous issue set the scene.
Keywords: energy policy; EPC; framework; life cycle cost analysis (LCC); retrofitting; sustainable heritage
The roof of Melin Daron, a derelict Grade II listed mill building in Aberdaron, on the Llŷn Peninsula in northwest Wales, had succumbed to leakages over two decades, which left some structural timbers exposed to the elements with some section decayed beyond repair. Mortar joints to the mill building’s exterior walls had almost perished with sections of the internal walls of the corn dryer section partially collapsed, leaving the structure in a precarious situation. In the short term some of the most important structural timber elements had to be repaired, along with repointing masonry and patch repairing the roof with a limited pot of money secured by the client while they sourced a larger funding pot through the National Lottery Heritage Fund (NLHF) to fully repair and preserve this unique building in the long term. This paper seeks to explain the thinking behind the steps taken to make the mill building weathertight while preserving and sympathetically altering historic details that give its unique character. It examines the identification and assessment of defects, before considering various options for conservation and repair.
Keywords: preserve; conservation; historic fabric; authentic; traditional roofing; significance; historic detail
This paper describes the conservation and conversion of a disused metal water tower into a family home. As well as being engineering exemplars, water towers have historically been vertical and legible landmarks in the landscape. They have the capacity to reinforce a sense of place, evoking our shared industrial history and inspiring connections to our past. Challenges for the project included planning, the dilapidation of the steel structure and preserving and amplifying the character of the primary structures. The focus of this design has been to connect the hitherto mechanical structure to nature: sunlight, views, air, foreground, background, fields, trees, horizon and sky.
Keywords: reuse; water tower; biomimetic structure; community build
Volume 12 Number 3
This paper looks at the opportunities presented by the latest monitoring technology to minimise risk from movement, deformation or variations in environmental conditions such as noise, dust and vibration. Secondly, it outlines the associated methods used to review, analyse and validate monitoring sensor triggers in the cloud. Lastly, it investigates how a proactive approach to monitoring can reduce legal risk, engage stakeholders and improve public relations.
Keywords: geospatial; wireless monitoring; deformation; environmental; digital twins
The UK has some of the oldest buildings in Europe. They are also some of the worst performing in terms of energy performance. In tandem with these issues the UK has committed to making a substantial reduction in CO2 emissions. UK homes are currently responsible for almost 20 per cent of CO2 emissions. This leaves little option other than to make considerable progress with the retrofitting of homes to improve their energy performance. This is a technical process, however, and can introduce risks to building and their occupants. Examples exist of homes being retrofitted with disastrous consequences. Some of these issues can be due to the lack of thorough examination of a home before it undergoes a retrofit. This paper proposes a method that provides a detailed pre-retrofit assessment of a home, to fall in line with PAS 2035, a standard that provides guidance around publicly funded retrofit in the UK.
Keywords: retrofit; building performance; pathology; energy pathology; defects; energy
This paper considers the impact and relevance of consequential losses in commercial property claims. As with all civil claims relating to property, the amount of damages sought should be a reflection of the claimant’s loss as a result of the breaches of covenant. In some instances, this is much more than the cost of the works required to remedy any physical breaches of contract. By the same token, due to the effect of section 18(1) of the Landlord and Tenant Act 1927, the loss can be significantly less than the cost of works. This is because section 18(1) seeks to limit damages for breaches of repairing obligations in leases to the impact of those breaches on the value of the landlord’s interest under consideration, be it leasehold or freehold. Further, section 18(1) introduces the concept of supersession whereby the cost of remedying a breach of contract is negated by the subsequent actions of the landlord. For example, the cost of remedying cracking in an internal partition wall is rendered nugatory if the same wall is subsequently demolished by the landlord. The cracking is irrelevant and no loss has been suffered. Whereas the preparation of a schedule of dilapidations is an essential first step in calculating the claimant’s loss, the cost of works arrived at through the costed schedule should be seen as exactly that — an essential first step. Consideration also needs to be given to whether the scheduled works are actually representative of the consequences of the breaches on the value of the interest. This will entail looking at the likely future of the building following the end of any tenancies, the state of the property market at the time those tenancies end and in particular whether rental levels are stable, volatile or somewhere in between. In many instances, this will involve discussion with practitioners in other disciplines associated with the property cycle. As important as the consideration of valuation, diminution and supersession to the assessment of loss is the analysis of the many different areas in which consequential losses may apply. These are complicated and potentially taxing areas but are no less relevant to the calculations of loss as those posed by the principles expressed by section 18(1). This paper seeks to explore the principles surrounding consequential losses so that practitioners will have an understanding to enable them to consider the types and magnitude of those applying to their various situations.
Keywords: dilapidations; consequential losses; loss of rent; quantifying loss
The Energy Performance of Buildings Directive (EPBD) is the European Union’s main policy instrument for reducing the built environment’s contribution to climate change. Energy Performance Certificates (EPC) are a tool of this policy, providing buildings with a performance rating. In the UK these have become the benchmark by which the Minimum Energy Efficiency Standards (MEES) are judged, rendering residences lower than an E illegal to rent out. This has pushed property owners to undertake energy retrofitting interventions to ensure compliance. In traditional buildings this is potentially problematic. Buildings of this type rely on permeability to control moisture dynamics; the insertion of less permeable barriers can interrupt their internal hygrometry leading to condensation, damp and decay. As a result, subsequent damage to the building fabric can bring energy policy into conflict with heritage conservation. Existing frameworks that attempt to mitigate the tension within these agendas often fall short in explicitly considering the the problem holistically. This research first asks if pressure from policy is leading to incompatible retrofits. Secondly, it aims to develop a holistic framework that unites heritage and energy agendas with current policy. An inductive, pragmatic approach was undertaken. Using a historic estate’s residential portfolio as a case study, condition surveys were carried out to assess whether properties retrofitted with secondary glazing were experiencing problems with condensation. The results of this were significant, supporting the argument that energy policy is driving incompatible retrofitting interventions. Exploratory data analysis was carried out on an existing EPC dataset to highlight inconsistencies with the EPC methodology. Finally, these findings were combined with questionnaire survey results, targeted at both professionals and occupants, to inform a decisionmaking framework that incorporated energy efficiency, heritage values, LCC, building assessment, occupant behaviour, with a feedback loop promoting a bottom-up approach to policy. This issue contains Part 1 which will set the scene, with Part 2, to be published in the next issue, presenting the methodology and results.
Keywords: energy policy; EPC; framework; LCC; retrofitting; sustainable heritage
This paper takes a close look at the mechanism of fire spread, highlights some of the fire safety challenges posed by heritage buildings and gives some practical advice on limiting the spread of fire while respecting the historic fabric.
Keywords: heritage buildings; refurbishment; fire spread; firefighter protection; firefighting; building works; stately homes; building protection; historic town centres; lath and plaster; cathedrals; HSG 168: Fire Safety in Construction.
In this paper, Liz Miller writes about her personal experience, with her husband Tom, of retrofitting and extending a brick and flint cottage to form a family home. As an architect, it is the realisation of a dream to work on one’s own house, and the paper explores the aims, design process, choices, experience of building and the final result. Taking this traditional Suffolk cottage, the paper describes the approach to both retrofit and new build, the materials that were used, the construction method, the relationship with the contractor, difficulties that were overcome through the process and the experience of living in the house. The project is an example of the power of good, simple, environmentally responsible design. The paper describes the decisions made to achieve a low-budget, comfortable, delightful home, carefully crafted for its inhabitants.
Keywords: retrofit; extension; sustainable; design; house
Volume 12 Number 2
Following on from the COVID-19 pandemic and the challenges faced during that period, valuers now have new issues to consider, as rapidly rising inflation and volatile interest rates not witnessed for a generation have had an effect on markets during 2022 — especially in the final quarter and going into 2023, as we see far reduced investment volumes and ongoing price discovery across European markets. This paper looks at how rising inflation and interest rates affect values and also how valuers need to develop new skills and understanding in valuing real estate assets in increasingly interconnected global financial markets.
Keywords: valuation; inflation; cost of capital; debt; sentiment; discount rates
By 2017 Lady Haig’s Poppy Factory was in a poor state of repair and in need of significant investment to bring it up to modern standards. It provided neither a suitable working environment for the ex-service men and women who worked in the building, nor was it fully accessible for visitors. Prior to this date a full range of options had been considered for the future of the factory, including potential relocation to another site outside of the city. The Grade C listing of the building in 2019 focused attention on the opportunities for improvement rather than demolition and a scope of works was put in place to refurbish the building. This case study describes the refurbishment programme and the scale of works which were required to bring it up to standard. It includes a particular focus on asbestos removal, replacement of roof coverings and rooflights, upgrading rainwater goods, repairs to walls and accessibility improvements to allow the building to meet the needs of both employees and visitors.
Keywords: Edinburgh; Poppy Factory; refurbishment; damp; asbestos; rooflights; roof; accessibility
The Party Wall etc. Act 1996 is an important piece of legislation which adjudicates in the midst of what are often the competing needs of neighbouring parties. Party wall surveyors are charged with the role of facilitating the exercise of the building owner’s rights while simultaneously safeguarding the interests of the adjoining owner. The Act confers upon the party wall surveyor the power and jurisdiction to properly discharge this role and laid out within the Act are a set of rules and directions that guide the surveyor as to the execution of that role. Nowhere within the four corners of the Act, however, is the party wall surveyor guided as to how to address the discharging of their role in the throes of a dispute between the parties as to the location of the boundary that separates their properties. The difficulty that arises is that much of the Act is predicated upon the location of the boundary being of settled knowledge or agreement. Indeed, knowledge of where the boundary lies goes in many instances to the heart of the operation of the Act. In his roles as third surveyor, the author is often met with referrals from appointed surveyors with differing views as to how to address a party wall matter in an instance in which there is disagreement between the parties as to the location of the boundary. This paper examines the arguments often put by surveyors in such circumstances, examines the extent of the surveyor’s powers in this regard under the Act, considers industry and judicial treatment of the matter, and sets out what is in the author’s view the conclusive position.
Keywords: jurisdiction; Party Wall etc. Act 1996; quasi-judicial; matters of law; Loost v Kremer; power to determine the location of the boundary; legal opinion
The Supreme Court has provided a landmark judgment in the law of private nuisance, overturning the decisions of the High Court and Court of Appeal, and being decided by a narrow 3:2 majority to create one of the most captivating judgments handed down in recent times for property litigation. This case concerned the appeal to the Supreme Court from the residents of luxury flats overlooked by the Tate Modern Gallery viewing platform. The viewing platform was once considered one of London’s best free viewpoints; indeed, the Supreme Court Justices describe it as a ‘striking view of London’. It has, however, caused a great deal of controversy with its neighbours over the last six years and their story has generated a remarkable amount of publicity. While it had previously been acknowledged that nuisance need not amount to physical interference, the question of whether there was, or should be, a right to prevent public overlooking had never been considered within the scope of private nuisance before.
Keywords: law; property; litigation; tort; nuisance; planning; privacy
This paper is a brief summary of the history of the evolution of the magazine in Esquimalt Harbour that served the Royal Navy’s Pacific Squadron, based in the same harbour after 1862 and which was intimately entwined with the development of the British colony of Vancouver Island after its foundation by the Hudson’s Bay Company (HBC) during the 1840s. It also chronicles the conservation, repair and informed restoration of the magazine site over the last ten years, in which latter endeavour the author became periodically involved after 2014, culminating in a five-month stay upon the island, as resident mason-conservator and default caretaker, between July and November 2021. The paper draws upon the author’s original 2014 condition survey, and upon a paper ‘Lime in Canada’ written by the author for the Building Limes Forum Journal in 2020, while incorporating subsequent research and additional material and correcting some of the errors and omissions in both earlier accounts. The project was driven by the deployment of traditional skills and like-for-like materials within the modern western Canadian context, within which such skills and such an approach are scarce, seeking to demonstrate the benefits of these to the built heritage across the province of British Columbia and to encourage their widespread use for the conservation and repair of traditional buildings in the province.
Keywords: lime; Cole Island; Pacific Northwest; Royal Navy architecture
The decline in high-street retail over recent years has prompted the UK Government to introduce the Levelling Up and Regeneration Bill, which at time of writing is making its way through Parliament. It aims, among other things, to reduce the number of vacant units on high streets in England and Wales by giving local authorities the power to put vacant high-street properties into rental auctions. This paper examines the key provisions of Part 10 of the Bill, as currently drafted, and the effect it is likely to have on the market for high-street properties.
Keywords: high street; town centres; regeneration; retail; hospitality; auctions; vacancy rates
Volume 12 Number 1
This paper looks at the technical and practical challenges faced during the conservation repair of a large 15th-century trussed roof structure of a Grade I listed church building. Urgent repairs were required after a section of ceiling plaster fell, after years of water ingress, resulting in tight programme and budget constraints, with the added pressure of a global pandemic. The paper describes the early stages of the contract, with surprising discoveries such as a hive of over 40,000 honeybees, bat roosts, a secondary roof structure, concrete and extensive deathwatch beetle decay. The engineer’s economic solutions to complex structural problems are explained, as well as architect designed details to address ongoing causes of decay, such as new ventilated eaves and ridge details. This paper sets out to describe how technical challenges were overcome, but also explains how opportunities were taken to introduce new oak carvings and lead details, to leave a legacy and add to the historic narrative of the building. This paper will be of particular interest to anyone working on ecclesiastical or listed building structures, where there has been a history of poor maintenance or previous repairs. It should offer technical information relating to a wide range of traditional building trades, but particularly structural repairs of historic timber structures.
Keywords: roof; structural repairs; carvings; lead; timber decay; conservation
This paper discusses the importance of groundwater risk assessment in basement waterproofing design. It discusses why it is required to allow the design of a cost-effective waterproofing system and also to determine whether the simple design approach in BS8485 can be used to assess risk from ground gases. It is also an important part of assessing the risk of vapour intrusion into basements from hydrocarbon contamination. External drainage for basements can be designed to be an effective and durable solution that lowers the hydrostatic pressure on the waterproofing system. It does require discharge to an outfall, however, and discharge to sewers is not appropriate, because water companies will not allow groundwater to be drained into public sewers. The rate of groundwater flow may also exceed the allowable discharge rates that are used in sustainable drainage (SuDS) design. This limits where external drainage can be provided to locations where a soakaway or a watercourse is available for discharge. The same constraints should also apply to cavity drain discharges. Where a basement is located in hydrocarbon contaminated groundwater or ground gas is present (such as methane or carbon dioxide) it is important to complete an appropriate risk assessment that considers whether flow into the basement will be via gas/vapour phase migration above the groundwater or dissolved phase below it. The simple screening and points system in BS8485 is not suitable where basements are below the groundwater table. The durability of materials (membranes, cavity drains, etc.) in contact with contaminants also needs consideration. Where contamination such as dissolved methane is present, cavity drains will require intrinsically safe pumps. Groundwater and contamination intrusion assessments are best completed by qualified ground engineering professionals and SoBRA accredited risk assessors for permanent gas and/or vapour intrusion respectively.
Keywords: basement waterproofing; groundwater; ground gas; vapour intrusion
This paper provides a detailed overview of how to validly exercise a break clause in a lease. While straightforward in theory, break notices frequently end up before the courts as the margin for error is small and implications high. There have been several high-profile cases in recent years where the validity of break notices has been challenged as the break clause has not been complied with ‘to the letter’. If successful, this will often result in the lease continuing (including obligations relating to payment of rent) until the lease expires or terminates for some other reason. This paper addresses some of those challenges, including ensuring valid service of a break notice and compliance with common conditions attached to the break (such as returning the property with vacant possession and complying with the lease covenants). There is a wealth of case law in each of these areas, with this paper providing an insight on the key issues to be aware of, and most notable reported cases.
Keywords: service; conditions; vacant possession; Mannai; Capitol Park
To limit global warming, a rapid reduction in the carbon emissions from our buildings is required. Heating buildings contributed to 17 per cent of the UK overall carbon emissions in 2018 which is why it is important we look to decarbonise the heating systems that serve our buildings. In 2020, only 7.9 per cent of the energy to heat our buildings came from renewable sources. In the UK, existing heating is predominantly by natural gas. The most significant challenge is the rural buildings that are not served by mains gas but have oil supplies, due to the high carbon content of this fuel. The Diocese of Gloucester was invited to participate in a research project carried out by Historic England into viable methods of low and zero carbon heating in churches and their associated buildings. The focus of this research explores oil-fired heating systems as this fuel produces more carbon dioxide emissions than other fuels used to heat buildings. The key finding from this research is that no single heating technology is recommended for either all historic buildings or even each historic building type. Across the six case studies, air source heat pumps, biomass and electric heating were recommended in an equal proportion of cases. It is not possible to determine the most viable heating technology without carrying out a detailed technical feasibility study at the early concept stage of a project. The recommended heating technology depends on many factors including the building’s site and location, the size and form of the buildings, the use and operation of the buildings, the condition of the existing heating system and the existing utility infrastructure. The wider background to this research includes the 2030 net zero carbon target set by the Church of England and the UK government’s 2050 net zero carbon target.
Keywords: churches; decarbonisation; heating; oil; rural
The first part of this paper offers a brief overview of the history and use of lime mortars through time, from early history up to the present day. It describes the uses and methods of various intermixtures to ensure best results in building practices. It gives examples of the use of lime mortars in important historic buildings, and explains their advantages and disadvantages. The second part of the paper features two case studies that document and discuss the use of lime mortar in the repair of two historic buildings in Norfolk, England..
Keywords: lime; hot lime; conservation; slaked; hydraulic
The Traditional Buildings Health Check (TBHC) scheme in Stirling was set up in 2013 as a fiveyear pilot to support owners of older buildings to tackle repairs. It also aimed to effect culture change in attitudes to proactive maintenance, encouraging owners to undertake repairs regularly. The scheme has been very successful and continues to be delivered by the Stirling City Heritage Trust, recently expanding beyond the city boundary. With increasing concerns over the impact of climate change, the TBHC has a role to play is supporting owners to ensure that their buildings are in good repair and dry before installing appropriate measures to improve their energy efficiency. The scheme is currently unique in Scotland but there is potential for expansion elsewhere to support tackling disrepair and the climate emergency.
Keywords: proactive maintenance; conservation; repair; Stirling; energy efficiency
With one quarter of Britain’s mammals in serious decline and one-third of those most under threat being our more elusive bats, people who own, manage or access a variety of buildings are playing an ever more vital role in helping to conserve wildlife, often without even realising it. Buildings have become important roosting sites for bats, including houses, bridges, barns, mines, and historic buildings and churches. As older structures that have escaped modernisation, churches can provide ideal habitats for bats. In small numbers, bats in churches often go unnoticed, but where they roost in large numbers, or where multiple species use the same church, a conflict can arise between the wildlife and the community using the building and caring for the artefacts inside. In contrast to residential and commercial buildings, where bats and people are separated by a ceiling, churches often have open-roof architecture. This means that bat droppings and urine can damage historic items, the fabric and interior of the church, and create an unmanageable cleaning burden for the church community. This is why the Bats in Churches project is so important. This partnership between the Church of England, Historic England, Natural England, Bat Conservation Trust and Churches Conservation Trust was granted funding by the National Lottery Heritage Fund in 2018 and runs through 2023. The project brings together ecologists, church architects and heritage experts to trial and implement systems to manage the issues created by bats in churches, through a specially designed licence. The UK has 17 breeding bat species. Sadly, the loss of natural roosting sites coupled with factors such as intensive agriculture and urbanisation, including increasing levels of light pollution, have all had a dramatic impact on bat populations, which have seen serious declines in the last century. As well as making up a significant proportion of Britain’s mammal biodiversity, bats are indicator species. This means changes to our bat populations can reveal wider changes to local wildlife populations signalling the health of the environment upon which we all ultimately depend. This is why all species of bat in the UK and their roosts are protected by law. This means it is illegal to damage, destroy or disturb any bats or their roosts without having taken the necessary precautions and sought the correct advice from the Statutory Nature Conservation Organisation (SNCO) for your country. In England, this is Natural England, via the Bat Conservation Trust. This does not mean, however, that building work, roof repairs and other maintenance works cannot take place. It is entirely possible to carry out works alongside resident bats, but it requires careful planning and consideration of timings. This paper will discuss the law relating to bats and building works. It will cover how bats use churches and other buildings, and the impact they can have on church interiors and communities. It will consider the practicalities of surveys and licensing and will describe some interventions and mitigation solutions created by the Bats in Churches project.
Keywords: bats; churches; heritage; buildings; wildlife; biodiversity; ecology
