Dr Matthew Brooke-Peat

The use of materials and products with sustainable credentials could potentially improve resource productivity and aid sustainable development. In order for such items to be widely adopted, the construction industry would need to overcome the barriers common to specification practice. The conservative nature of specifiers has been described by previous research, whereby familiar items are recurrently selected from a trusted palette and alternative solutions are only sought when the palette fails. The body of literature recognizes manufacturers as influential sources of information and has also shown that specifiers often make informal contact with companies known to them when faced with a specification problem. However, some existing work indicates that the active selection phase is not the only time when the decisions of specifiers can be influenced. Promotional material encountered during a state of passive awareness could be retained for later use, thereby expanding the specifiers’ palette. This paper reports and discusses the results of a quantitative inquiry into the extent of publicity currently afforded to materials and products with sustainable credentials in mainstream construction industry periodicals. The findings reveal that problems in the marketing of these items may be acting as a barrier to their uptake by restricting the specifiers’ awareness of the available options.

This seminal text on applied research in architectural technology will enlighten, inform and challenge readers.

© 2018 The International Masonry Society (IMS). Battersea Power Station was the largest brickwork building in Europe when it was completed in 1955. The building is a major London landmark. It was closed in 1983 and part of the roof has since been removed, leaving the interior exposed to the weather. The building is being redeveloped to provide a mix of office, residential and retail accommodation. Grade II* listed status protects the former power station. The external aesthetic is of architectural significance and the internal appearance considered to be industrial archaeology, both are to be largely preserved. There were concerns that upon completion the residual moisture within the masonry, and its drying out driven by the conditioning of the internal spaces, could generate problems, such as mould growth, efflorescence, condensation and frost damage. This paper describes a programme of sampling and testing to evaluate the initial moisture profile though the brickwork, and its physical and hygric properties. Findings are presented from hygrothermal simulations undertaken to investigate the risk of the various moisture related problems occurring in use. The presented outputs illustrate the predicted behaviours through moisture contents, relative humidity, and temperatures plots. The making of judgements on identified risks are explained. Further works to assess risks at specific local features are ongoing.

The use of materials and products with sustainable credentials could potentially improve resource productivity and aid sustainable development. In order for such items to be widely adopted, the construction industry would need to overcome the barriers common to specification practice. The conservative nature of specifiers has been described by previous research, whereby familiar items are recurrently selected from a trusted palette and alternative solutions are only sought when the palette fails. The body of literature recognizes manufacturers as influential sources of information and has also shown that specifiers often make informal contact with companies known to them when faced with a specification problem. However, some existing work indicates that the active selection phase is not the only time when the decisions of specifiers can be influenced. Promotional material encountered during a state of passive awareness could be retained for later use, thereby expanding the specifiers' palette. This paper reports and discusses the results of a quantitative inquiry into the extent of publicity currently afforded to materials and products with sustainable credentials in mainstream construction industry periodicals. The findings reveal that problems in the marketing of these items may be acting as a barrier to their uptake by restricting the specifiers' awareness of the available options.

The use of materials and products with sustainable credentials could potentially improve resource productivity and aid sustainable development. In order for such items to be widely adopted, the construction industry would need to overcome the barriers common to specification practice. The conservative nature of specifiers has been described by previous research, whereby familiar items are recurrently selected from a trusted palette and alternative solutions are only sought when the palette fails. The body of literature recognizes manufacturers as influential sources of information and has also shown that specifiers often make informal contact with companies known to them when faced with a specification problem. However, some existing work indicates that the active selection phase is not the only time when the decisions of specifiers can be influenced. Promotional material encountered during a state of passive awareness could be retained for later use, thereby expanding the specifiers' palette. This paper reports and discusses the results of a quantitative inquiry into the extent of publicity currently afforded to materials and products with sustainable credentials in mainstream construction industry periodicals. The findings reveal that problems in the marketing of these items may be acting as a barrier to their uptake by restricting the specifiers' awareness of the available options.

Internal Wall Insulation (IWI) retrofits reduce heat loss from homes, increase comfort and reduce fuel bills, however, they can result in unintended consequences. This paper uses thermal modelling to show that if only one side of a party wall is fitted with IWI, the surface temperature of the uninsulated side will reduce, and its risk of mould growth and surface condensation increases. This has potential implications for works under the Party Wall etc. Act 1996 that is applicable in England and Wales, and the room by room approaches to IWI retrofits.

The potential to reduce energy demand and thus carbon emissions from the built environment is considerable. As well as benefitting the environment, good energy efficient retrofits can reduce energy bills and improve thermal comfort; however, the discrepancy between expected and actual performance can mean the anticipated benefits are not fully realised. If thermal upgrades are to be accepted and adopted the retrofit solutions should be simple and effective and deliver the performance expected. This paper summarises part one of a two-stage Saint-Gobain funded research project which investigated the change in thermal performance resulting from a number of ‘off-the-shelf’ thermal upgrade measures applied to a circa 1900 solid wall end terrace house situated in an environmental chamber. The project involved a phased programme of upgrades to the thermal elements of the test house; thermal upgrades were applied either individually or in combination. Presented are the quantitative measurements of thermal performance at each test phase which are compared against baseline values measured while the test house was in its original condition. The heat loss coefficient (HLC) of the fully retrofitted dwelling was 63 % lower than the dwelling in its baseline condition. 72 % of the HLC reduction was attributable to the application of a hybrid solid wall insulation system. The fully retrofitted test house had a measured air permeability value that was 50 % lower than in its baseline condition. There was close agreement between the calculated upgrade U-value and that measured in situ for most thermal upgrade measures. The primary conclusion of the paper is that dwellings of this type, which represent a significant proportion of the UK housing stock, have the potential to be retrofitted using off-the-shelf thermal upgrade measures to a standard which meets design expectations and can significantly reduce their requirement for space heating and currently associated CO2 emissions.

© 2017 Elsevier LtdMould growth and surface condensation are problems for many dwellings, and the retrofitting of insulation can increase the risk of these occurring. This is especially the case for historical solid wall properties receiving external wall insulation (EWI), which often have architectural details at the roof eaves that cause discontinuities in the insulation and so can result in excessive thermal bridging. This paper presents the results of an investigation into retrofitted solid wall properties where modelling is used to investigate the problem and effectiveness of insulated coving products which are designed to reducing thermal bridging. Thermal modelling is undertaken to establish the optimum design to reduce risk. The insulated coving was found to be effective in reducing thermal bridging in all the scenarios investigated and to reduce moisture risks occurring in some solid walls situations.

It is not practicable to test every aspect of all the buildings that are built. As we understand the behaviour of buildings from field and laboratory tests the data can be used to produce generalised assumptions about the way a building, and its component parts will behave. These models simulations are now an integral part of our understanding of the performance of buildings. While the assumptions made in models and simulations can be relatively imprecise when first developed, as their development is advanced the models become more detailed, reliable and intelligent. Researchers are constantly updating and calibrating the sensitivity of their models, using new data from the field and in-use studies to improve the reliability and accuracy with which the models can operate. The construction industry is heavily reliant on the use of models and simulations to perform a variety of design and analysis calculations, for predicting energy consumption and performance of finished buildings, and to demonstrate compliance with regulatory or voluntary performance standards.

ARC Building Solutions Ltd manufacture, market and distribute a range of party wall cavity barriers. Part L of the Building Regulations (HM Government, 2013) stipulates that when cavity barriers are used for edge sealing purposes, then the seal must be effective at restricting air flow between the party wall cavity and the external wall cavity or external environment (Figure 1). The Building Control Alliance (2011) describes how an edge seal is to be judged as being effective in a qualitative manner. However, there is currently no standard test for quantitatively demonstrating the effectiveness of edge sealing using a cavity barrier product. ARC Building Solutions Ltd wished to quantify the effectiveness of the edge seal that could be achieved using the Company’s products under test conditions. This information could prove useful when engaging designers, building control bodies and warranty providers. As there is currently no quantitative benchmark for what is deemed to be an effective edge seal this project aimed to compare the performance of a recognised ‘current practice’ solution against ARC Building Solutions Ltd.’s T-Barrier, and as far as possible compare these to an accepted effective edge seal for a number of different party wall and external wall cavity widths. In addition to this comparative testing, this project may also assist in the development and application of a standardised ‘Edge Seal Test’ for which there is understood to be no current standard or specific precedent. Whilst the test rig may not be fully representative of the actual construction of a party wall/external wall junction in situ, it is hoped that the results may provide insight as to how the performance of these products may compare in real building situations.

In the UK, it has become apparent in recent years that there is often a discrepancy between the steady-state predicted and the measured in situ thermal performance of the building fabric, with the measured in situ performance being greater than that predicted. This discrepancy or gap in the thermal performance of the building fabric is commonly referred to as the building fabric 'performance gap'. This paper presents the results and key messages obtained from undertaking a whole-building heat loss test (a coheating test) on seven new-build dwellings as part of the Technology Strategy Board's Building Performance Evaluation Programme. While the total number of dwellings involved in the work reported here is small, the results illustrate that a wide range of discrepancies in thermal performance was measured for the tested dwellings. Despite this, the results also indicate that it is possible to construct dwellings where the building fabric performs thermally more or less as predicted, thus effectively bridging the traditional building fabric performance gap that exists in mainstream housing in the UK.

It is recognized that there is often a discrepancy between the measured fabric thermal performance of dwellings as built and the predicted performance of the same dwellings and that the magnitude of this difference in performance can be quite large. This paper presents the results of a number of in-depth building fabric thermal performance tests undertaken on three case study dwellings located on two separate Passivhaus developments in the UK: one masonry cavity and the other two timber-frame. The results from the tests revealed that all the case study dwellings performed very close to that predicted. This is in contrast with other work that has been undertaken regarding the performance of the building fabric, which indicates that a very wide range of performance exists in new-build dwellings in the UK, and that the difference between the measured and predicted fabric performance can be greater than 100%. Despite the small non-random size of the sample, the results suggest that careful design coupled with the implementation of appropriate quality control systems, such as those required to attain Passivhaus Certification, may be conducive to delivering dwellings that begin to ‘bridge the gap’ between measured and predicted fabric performance.

This book focuses on the impacts of the built environment, and how to predict and measure the benefits and consequences of changes taking place to address sustainability in the development and building industries.

The methodology used for measuring the thermal performance of fabric retrofit systems which were applied to a solid wall UK Victorian house situated within an environmental chamber is explored in detail. The work describes how steady-state boundary conditions were approximated, then repeated at the Salford Energy House test facility. How established methods of measuring the fabric thermal performance of buildings in situ were adapted to test the effectiveness of retrofit measures within a steady-state environment. The results presented show that steady-state boundary conditions enable the change in fabric heat loss resulting from the retrofit of a whole house or individual element to be measured to a level of accuracy and precision that is unlikely to be achieved in the field. The test environment enabled identification of heat loss phenomena difficult to detect in the field. However, undertaking tests in an environment devoid of wind underestimates the potential reduction in ventilation heat loss resulting from an improvement in airtightness, and hides the susceptibility of retrofit measures to various heat loss mechanisms, such as wind washing. The strengths and weaknesses of the methods employed, the Energy House test facility, and a steady-state environment, for characterising retrofit building fabric thermal performance are demonstrated.

Purpose: The coheating test is the standard method of measuring the heat loss coefficient of a building, but to be useful the test requires careful and thoughtful execution. Testing should take place in the context of additional investigations in order to achieve a good understanding of the building and a qualitative and (if possible) quantitative understanding of the reasons for any performance shortfall. The paper aims to discuss these issues. Design/methodology/approach: Leeds Metropolitan University has more than 20 years of experience in coheating testing. This experience is drawn upon to discuss practical factors which can affect the outcome, together with supporting tests and investigations which are often necessary in order to fully understand the results. Findings: If testing is approached using coheating as part of a suite of investigations, a much deeper understanding of the test building results. In some cases it is possible to identify and quantify the contributions of different factors which result in an overall performance shortfall. Practical implications: Although it is not practicable to use a fully investigative approach for large scale routine quality assurance, it is extremely useful for purposes such as validating other testing procedures, in-depth study of prototypes or detailed investigations where problems are known to exist. Social implications: Successful building performance testing is a vital tool to achieve energy saving targets. Originality/value: The approach discussed clarifies some of the technical pitfalls which may be encountered in the execution of coheating tests and points to ways in which the maximum value can be extracted from the test period, leading to a meaningful analysis of the building's overall thermal performance.

To meet targets on fuel poverty, energy efficiency and carbon emissions existing homes need to be more energy efficient. We report the results of a participatory action research project to explore the challenges associated with energy efficiency retrofit programmes and ways to better implement future schemes. Six focus groups were held with 48 participants from a range of energy efficiency roles. Data were analysed thematically using the research question “What are the challenges presented by implementing energy efficiency retrofit programmes”. We identified four themes in the data: Funding mechanisms; Predicting performance; Installation; and People. Challenges include funding mechanisms for retrofit programmes resulting in insufficient time to plan, publicise, implement and evaluate a scheme and insufficient flexibility to specify the most appropriate intervention for individual homes. Site workers sometimes need to adapt retrofit designs because of insufficient detail from the designer and can equate quality of installation with quality of finish. Landlords and occupier behaviour can impact on the programme's success and there is a need for greater information on benefits for landlords and for energy behaviour change interventions run alongside retrofit programmes for occupiers. There is a need for outcome evaluations of retrofit schemes with the results shared with stakeholders.

Leeds was designated a core city for trialling the Government’s Green Deal domestic energy efficiency policy. Leeds Beckett University undertook a monitoring and testing program on 65 dwellings to investigate the effectiveness of the insulation measures installed and to understand any underperformance. This report outlines the findings from a series of investigations including; surveys, air tightness tests, co heating tests, in situ U-value tests, hygrothermal and thermal bridging modelling, in use monitoring and occupant interviews. The surveys revealed that the ‘whole house approach’ to retrofit was, more often, missing, and quality assurance around insulation detailing was regularly absent, leading to avoidable errors and potentially embedding problems in the installations. Furthermore, moisture issues were, in the majority of instances, over-looked or made worse despite over half the sample having some form of damp. Despite this, energy savings were observed and the appearance of the dwellings were improved, thus apparent satisfaction was generally high, even though the installs were imperfect and moisture problems were introduced. Hygrothermal modelling of IWI cases suggests that thermal bridging at party walls can increase by more than 60% and that there could be potential for rot to embedded timbers. Insulation was recorded to reduce background ventilation of the dwellings by around 25% (a factor unaccounted for in government energy models), although some dwellings were still left with air tightness levels worse than modern day UK Building Regulations limits and replacing wet plaster with IWI was seen to undermine the performance of the insulation. The heat loss coefficient of three homes were tested and showed improvements of 25% and 56% for full retrofits with IWI, and 8% for a party wall retrofit; ¾ of these savings were achieved by fabric improvements and the final quarter from incidentally making dwellings more air tight. The before and after in use monitoring suggested the average savings in energy consumption from all retrofit types (EWI, IWI or other) were between 20% and 29%, although small sampling periods limits the certainty of the results. More reliably it was observed that comfort conditions improved; before the retrofit, 14 of the homes were experiencing discomfort from cold; the retrofit brought on average 2 /3 of uncomfortable homes into more reasonable comfort bands. Nearly all of the occupants had positive experiences, although no householders had to pay for the retrofit, reporting being warmer, bringing unused rooms back into operation and feeling more pride in their homes and communities. A variety of perceptions and behaviours were observed around set point temperatures, use of heating controls and motivations for using energy, all of which contribute to make a complex policy landscape. There is huge potential for domestic retrofit and although this research suggests the current

The benefits and risks associated with installing internal wall insulation (IWI) and thin internal wall insulation (TIWI) retrofits into solid wall homes are researched and evaluated for BEIS. In order to deliver this, a holistic approach was adopted and the project was split into four main sections, each of which has an accompanying Annex to this summary report: Annex A: Review of existing literature as well as primary investigations using house surveys, householder questionnaires and installer focus groups into the sociotechnical barriers to IWI and TIWI. Annex B: Technical evaluation of the performance of IWI and six novel TIWI retrofits installed in field trial solid wall Test Houses using before and after building performance evaluations. Annex C: Modelling of the impact on annual energy consumption, EPC rating, overheating risk, condensation risk and moisture accumulation made by IWI and TIWI retrofits in a range of UK house archetypes. Annex D: Laboratory testing of test walls using hygrothermal chambers to quantify the change in moisture and thermal performance of solid brick walls when they are insulated with IWI and TIWI to determine how weather