Building Research Establishment Research Articles

How Accurately Does Breeam Measure Sustainability?

The aim of this paper is to review the Building Research Establishment Environmental Assessment Method (BREEAM) in terms of how adequately it addresses sustainability. To achieve the aim, a literature review and semi-structured interviews with BREEAM assessors were conducted. Relevant literature has been reviewed to establish the meaning behind the concept of sustainability and to compare BREEAM with other environmental assessments in the built environment. An in-depth review of BREEAM and sustainability was then carried out through a series of semi structured interviews with seven experts in the field. It is concluded that BREEAM is an efficient tool in establishing the environmental performance of buildings through design and procurement. However it does not address the concept of sustainability in its entirety choosing to focus more on the environmental aspects. Some inconsistencies in its methods were also observed.

Energy Efficient Construction Methods in UK Dwellings

This paper examines the thermal performance of housing in the UK and the associated costs for different fabric construction methods of the envelope for a typical four bedroom detached house. The energy ratings were assessed using the UK Government’s Standard Assessment Procedure (SAP), which is based on the Building Research Establishment Domestic Energy Model. The capital costs were estimated from data published by the Building Cost Information Services applied to Leicester UK area in 2011. Through alterations to the dwelling fabric alone, a reduction of 30.1% in carbon emissions of the base property could be achieved. Standard methods proved to be as effective as alternative methods at reducing carbon emissions by 22.6% for an average capital cost increase of 9.1% against the base property. This was equivalent to an extra cost of £13.7 for each kg of CO2 emissions reduction. It was found that alternative methods could reduce carbon emissions by 20.5% for an extra cost of 18.4% over the base property. The optimum construction method that would help achieve the UK government’s carbon emissions target was also discussed. The paper also discusses the methods for improving energy efficiency in new extensions to existing dwellings, using a typical solid-wall terraced house with a new single storey extension, as a case study. In this study, it was found that by increasing refurbishment costs by only 4.7% could result in carbon emissions reduction by 21.7%.

Influence of Mineral Admixtures on early Shrinkage of Ordinary Concrete

In this paper the influence of mineral admixtures on early shrinkage of ordinary concrete with the same water-binder ratio is studied by self-made equipment and CABR-NES deformation instrument developed by China Academy of Building Research Institute. All concrete specimens are cured with one surface exposed to air and others are covered with plastic film. The replacement ratio of mineral admixtures is 10%, 20% and 30%, respectively, and a mixture of a combination of both fly ash and slag is also studied. The results indicate fly ash reducing the early shrinkage of ordinary concrete, and the shrinkage decreases with the increasing of replacement ratio, but the effect is not so significant when the replacement ratio is above 20%. Slag also reduces the early shrinkage of ordinary concrete, and the shrinkage decreases with the increasing of replacement ratio, but the effect is not so significant when the replacement ratio is below 20%. Mixture with a combination of both fly ash and slag has lower shrinkage than mixture with fly ash.

Influence of Mineral Admixtures on early Shrinkage of Ordinary Concrete

In this paper the influence of mineral admixtures on early shrinkage of ordinary concrete with the same water-binder ratio is studied by self-made equipment and CABR-NES deformation instrument developed by China Academy of Building Research Institute. All concrete specimens are cured with one surface exposed to air and others are covered with plastic film. The replacement ratio of mineral admixtures is 10%, 20% and 30%, respectively, and a mixture of a combination of both fly ash and slag is also studied. The results indicate fly ash reducing the early shrinkage of ordinary concrete, and the shrinkage decreases with the increasing of replacement ratio, but the effect is not so significant when the replacement ratio is above 20%. Slag also reduces the early shrinkage of ordinary concrete, and the shrinkage decreases with the increasing of replacement ratio, but the effect is not so significant when the replacement ratio is below 20%. Mixture with a combination of both fly ash and slag has lower shrinkage than mixture with fly ash.

Retrofitting Listed Buildings: Measures, Savings and Requirements

The paper presents a case study where the energy demand for a listed building constructed in 1900 is reduced. Many older buildings are listed and have restrictions that include the entire building or that include only its exterior. For the building presented, only its exterior facade is listed. The paper demonstrates measures for the improvement of the thermal insulation of the building with solid brick walls. Durable customised measures are shown. The customised measures are required not to change the overall exterior architecture as the building is considered to contribute to the uniqueness of the local urban environment and therefore listed. The reduced energy demand, related to individual measures, is estimated and building physics requirements are addressed together with the economic options for evaluating the profitability. Tightened requirements to the thermal insulation of new buildings and the resulting demand for a reduction of the energy consumption for heating and comfort, in order to re- duce CO2 emissions, mean that existing and especially older buildings are categorised as having a very low thermal stan- dard compared with today's requirements. Therefore, there is an increased interest in improving the thermal insulation standard of many existing and older buildings. However, many older buildings have restrictions that protect the entire building or that protect only its exterior. Therefore custom- ised solutions reducing the energy consumption are needed for these buildings. Moreover, close attention should focus on preventing degradation of the existing construction when the energy needed for heating and thermal comfort of a building decreases, as a result of measures to improve the thermal insulation. Besides lower heating costs and reduced CO2 emissions, the improvements of the standard of insula- tion could contribute to the elimination of other aspects of discomfort. The aim of the paper is to show solutions that improve the thermal insulation standard of a building with a listed exterior facade. The paper includes technical solutions for improving the thermal insulation standard by showing cus- tomised thermal insulation measures of the building enve- lope. It also addresses issues that must be considered in order to prevent moisture-related degradation of the original build- ing. Furthermore, a simple and accurate method for estimat- ing the decreased energy demand after improvements is ap- plied. Finally, the profitability of the measures is evaluated. The paper is based on guidelines on how to improve the thermal insulation of existing buildings and blocks of flats published by the Danish Building Research Institute (1).

Understanding and predicting construction waste

For the last 12 years, Building Research Establishment (BRE) has been working on developing better data in terms of the amount and type of waste being produced as a result of construction activity. The means of collecting and aggregating these data have been refined over the years to arrive at the current large-scale and long-term benchmarking exercise being undertaken by way of BRE’s site waste management planning tool – Smartwaste Plan. Concurrently, a 3 year project ‘Understanding and predicting construction waste’ has been funded by Defra to develop robust reporting procedures and detailed waste benchmarks. A further objective is to demonstrate the use of such benchmarks as a means of predicting the amount and type of waste likely to be produced as a result of construction activity on a local and regional basis. This is potentially useful in working out gaps in suitable resource management facilities or under/over capacity relating to reprocessing specific waste materials. Interim results from these activities, conclusions and future/ongoing work are summarised in this paper. A range of performance indicators for waste arisings from new build construction were produced for a variety of different project types and for different waste types. These performance indicators have been use to produce benchmarks for standard, good and best practice.

Dual Barrier Protected Membrane Roof Assemblies

Abstract Durable roof design is accomplished through the selection of proven high performance materials that are detailed to accepted standards and assembled by skilled tradespeople. Leak prevention is a high concern of building owners that can be addressed by protected membrane dual barrier roofs. The case studies herein illustrate the improvement of the membrane and insulation. Typically, roofing membranes are generally the only barrier for managing moisture (rain, vapor pressure, air movement) through a building’s roof. The position of the insulation is also an important consideration because insulation on the membrane’s exterior protects it from thermal shock and generally extends the roof membrane’s service life. Largely for this reason, protected roof membranes have been recognized for their superior performance over that of conventional roofs because the insulation protects the primary roofing membrane from wide temperature fluctuations, solar radiation, and foot traffic over the roof membrane. The concept of dual barrier roofing simply includes (a) designing a new roof assembly to include at least one “extra” layer of moisture protection or (b) simply designing the standard existing roof components to resist the elements in order to further improve the performance of a protected roof assembly. Case studies are presented that summarize the physical attributes for dual barrier roofing, both in new construction and for roof replacement/renewal projects. Measured performance comparisons indicate that a dual barrier protected membrane roof can be on the order of 10 % to 20 % more thermally efficient that a typical protected membrane [Tobiasson, W., and Richard, J., “Moisture Gain and Its Thermal Consequence for Common Roof Insulations,” NRCA Fifth Conference on Roofing Technology, US Army Cold Regions Research & Engineering Laboratory, Gaithersburg, Maryland, April 1979; Beech, J. C., and Saunders, G. K., “The Performance of Lightweight Inverted Flat Roofs, Building Research Establishment,” NRCA Second International Symposium on Roofing Technology, Princes Risborough Laboratory, Buckingshamshire, United Kingdom, September 1985]. Additional performance and service life benefits are also summarized.

Experimental investigation of structure vulnerabilities to firebrand showers

Attempting to experimentally quantify the vulnerabilities of structures to ignition from firebrand showers has remained elusive. The coupling of two facilities has begun to unravel this difficult problem. The NIST Firebrand Generator (NIST Dragon) is an experimental device that can generate a firebrand shower in a safe and repeatable fashion. Since wind plays a critical role in the spread of WUI fires in the USA and urban fires in Japan, NIST has established collaboration with the Building Research Institute (BRI) in Japan. BRI maintains one of the only full scale wind tunnel facilities in the world designed specifically for fire experimentation; the Fire Research Wind Tunnel Facility (FRWTF). The present investigation is aimed at extensively quantifying firebrand penetration through building vents using full scale tests. A structure was placed inside the FRWTF and firebrand showers were directed at the structure using the NIST Dragon. The structure was fitted with a generic building vent, consisting of only a frame fitted with a metal mesh. Six different mesh sizes openings were used for testing. Behind the mesh, four different materials were placed to ascertain whether the firebrands that were able to penetrate the building mesh assembly could ignite these materials. Reduced scale test methods afford the capability to test new vent technologies and may serve as the basis for new standard testing methodologies. As a result, a new experimental facility developed at NIST is presented and is known as the NIST Dragon's LAIR (Lofting and Ignition Research). The NIST Dragon's LAIR has been developed to simulate a wind driven firebrand attack at reduced scale. The facility consists of a reduced scale Firebrand Generator (Baby Dragon) coupled to a bench scale wind tunnel. Finally, a series of full scale experiments were conducted to visualize the flow of firebrands around obstacles placed downstream of the NIST Dragon. Firebrands were observed to accumulate in front of these obstacles at a stagnation plane, as was observed when the structure was used for firebrand penetration through building vent experiments, due to flow recirculation. The accumulation of firebrands at a stagnation plane presents a severe threat to ignitable materials placed near structures.

Incorporating an economic measure in sustainability assessment

Breeam, The Building Research Establishment's environmental assessment method, is a suite of tools designed to measure the environmental performance of buildings. Although originally designed for a UK context, it has been adapted for and influenced a range of building rating systems worldwide. The domestic scheme, Ecohomes, was originally designed as an environmental assessment method. This paper analyses the spread of indicators used and seeks to address any gaps. Analysis of the indicators found that there is a very reasonable coverage of environmental indicators in the scheme, and this is complemented by a reasonable coverage of social indicators. However, there is a complete avoidance of the economic dimension. A means of incorporating an economic dimension should be considered to make the scheme a three-dimensional sustainability assessment method. The approach develops a sustainability ratio based on the existing scheme score to measure the environmental and social dimensions, while capital construction cost defines the economic dimension. It is possible that with further industrial consultation the approach could be transferred and applied to other building rating methods.

Fire Safety Assessment Research for High-Tech Plants

Most of the buildings for high-tech plants are fireproof and the process equipment in the clean room is in compliance with high-standard fire prevention evaluation regulations such as National Fire Prevention Association (NFPA), Factory Mutual (FM),and Semiconductor Equipment and Materials International (SEMI). However, fire management is usually neglected though fire protection higher than domestic fire control regulations is applied. Fireproof and smoke-proof design of the original buildings can be damaged due to expansion of production facilities, causing a potential danger of a fire. Cases of fires in domestic semiconductor manufacturing factories were explored in this research and claim settlements provided by MSIG Mingtai InsuranceCo.,Ltd., Taiwan to high-tech plants were analyzed for determination of the quantified weights used by the insurance companies when evaluating fire risks of a building. The fire safety badge promoted by Architecture and Building Research Institute, and Ministry of the Interior was also discussed for reference of fire safety assessments of high-tech factory buildings in the future.

Small Problem, Big Crisis: A Study on the Importance of Fire Separation in Tall Buildings

Risk is a concept that denotes the probability of the occurrence of dangers. The factors that generate fires and dangers are numerous, and always emerge in unapparent places. Once these factors are identified, a fire accident would happen and lead to great loss. For the fires happening in tall buildings that caused immense loss, the function of planned fire separation system was destroyed because the users had weak fire prevention concepts. One of the typical examples is the fire that happened and spread over Don-ke Building in Sijhih City, Taipei County, Taiwan. Based on the damage prevention concepts of property insurance agents, the study focused on the importance of the fire prevention management in tall buildings. The other part that was paid attention to is the Fire Safety Building strongly encouraged and propelled by the Architecture and Building Research Institute of Ministry of the Interior, with which the study conducted an investigation on fire risk management.

The Building Research Establishment

The Building Research Establishment

Sustainability as a Driving Force in Contemporary Library Design

The drive for energy efficiency arising from a growing awareness of the dangers of climate change is leading to new approaches to library design. The article explores the interaction between library architecture and sustainability by reviewing the many complex strategies employed for saving or recycling evermore scarce natural resources. Although the focus is upon energy consumption, the article also investigates how concepts of comfort and climate are changing under the impact of environmental sustainability. These topics are discussed mainly in the context of public and university libraries built over the past decade, with some reference to library designs still awaiting construction. The methodology is developed primarily through comparative case studies, exploring the approach to environmental sustainability under a number of headings drawn from widely employed environmental assessment methods such as BREEAM (Building Research Establishment Environmental Assessment Method), commonly employed in the United Kingdom and much of Europe; and LEED (Leadership in Energy and Environmental Design), the assessment tool frequently used to anticipate the environmental credentials of projects still on the drawing board in the United States and Asia. In many ways the architectural approach to the twenty-first century library is returning to the roots of the modernist library found in Scandinavia with its emphasis upon high levels of daylight, natural materials, social harmony, and contact with nature.

Radon concentrations in abandoned mines, Cumbria, UK: safety implications for industrial archaeologists

Abstract. This paper presents a number of surveys performed in a geographical area of the UK, part of which until recently was considered low radon risk. The Cumbrian region was identified by the Building Research Establishment (BRE) in its 1999 guide as an area without a significant radon problem in the built environment. The geology of the region, which includes the Northern Pennine Orefield is varied, but consists of granites, andesites, tuffs, carbonates, sandstones and shales. Mineralisation has taken place (mostly lead and copper ores) primarily along fault and fracture zones, one example being Copper Valley, northwest of Coniston village. This work quantifies the risk of exposure to radon in a number of abandoned mine environments. High radon levels, up to 28 589 Bq m−3, have been measured in parts of one mine. This study demonstrates that industrial archaeologists (such as the Cumbrian Amenity Trust Mining History Society or CATMHS members) and explorers of abandoned mines can be at risk from radon exposure and it proposes a management scheme to allow industrial archaeologists to continue exploration whilst minimising the risk to health from radon.

Breathable Walls — Sustainable Innovation for Future Built Environment

I won a major project just before I left BRE (Building Research Establishment, UK) in November 2008. The project was accepted for funding by the Technology Strategy Board (TSB) in the UK. The Technology Strategy Board is an executive non-departmental public body, established by the UK Government in 2007 and sponsored by the Department for Business, Innovation and Skills (formerly Department of Trade and Industry, DTI). The Technology Strategy Board is about supporting innovation, to stimulate technology-enabled innovation to help stimulate UK growth and productivity by removing barriers to innovation and accelerate the exploitation of new technologies. The project was to be funded under the technology priority: Components and Materials for Low Impact Buildings, which was intended to help development of innovative materials and components to be integrated into buildings to achieve the government’s target for zero carbon housing for new build by 2016. The proposed project would involve a development of a range of novel walling products manufactured using bioresin made from waste vegetable oils and natural fibres such as hemp and flax. Gypsum plasterboard was also included in the project proposal. The innovative biocomposite products would be ‘‘breathable’’ and have high thermal and acoustic properties. The materials should remove pollutants and moderate the humidity in the infiltrating air. These pollutants could be generated outdoors e.g. nitrogen dioxide, polyaromatics and particulates from traffic or be released indoors (e.g. VOCs and formaldehyde from building products). The products would be prefabricated to allow a high degree of airtightness in the construction of homes, but the breathable walls would allow sufficient air permeation and pollutants removal to ensure a low impact on the health and wellbeing of occupants. The products should contribute to a high rating required by the Code for Sustainable Homes [1]. The project required a participation of industrial partners, who are world leaders in design, production and distribution of construction products for the building industry. The production of the innovative product would fit well with the industrial partners’ business strategy for product development that would contribute to low impact, low carbon emission and energy efficient buildings. However, due to the novelty of the products, this would represent a considerable risk to the industrial company but the funding by TSB would alleviate this risk to make the project worthwhile and would contribute to the design of buildings that have ‘‘health and wellbeing’’ as the central core of consideration. Also considering the downturn situation being experienced by the construction industry, the knowledge transfer and spill-over would be an important add-on value to the project had it been funded by TSB. Indoor Air Quality and health and wellbeing were not part of the central business objectives of BRE; therefore the Environmental Consultancy and Indoor Air Quality Team was disbanded and I left BRE, the day before the announcement of funding by TSB. The project was abandoned. As there will not be future opportunity for me to work on this project, I would like to share the idea with you, maybe one day we can have innovative breathable walling products developed and incorporated into housings to contribute to the sustainable development

The design and construction of filled building platforms

Building platforms are described, and their purposes are explained. Historically, construction standards for engineered fill were not good, but following development of new specifications in the UK, and after major failures in Hong Kong, good practices were established to improve the construction of building platforms. In the UK this work was strengthened by the Building Research Establishment, with valuable contributions from individual authors. The paper summarises the advice in the literature in the context of almost 50 years' experience in the UK, central Europe and China, and sets out recommended procedures for constructing filled building platforms. Site practices in the UK and elsewhere do not always follow the established guidelines. Several examples of good practice and departures from best practice are provided, with some photographs. For legal and commercial reasons the cases are not identified.

A comparison of the UK Standard Assessment Procedure and detailed simulation of solar energy systems for dwellings

The drive to reduce worldwide carbon emissions that are directly associated with dwellings and to achieve a zero carbon home dictates that renewable energy technologies will have an increasingly large role in the built environment. The Standard Assessment Procedure (SAP), formulated by the Building Research Establishment (BRE), is the UK Government's approved methodology for assessing the energy ratings of dwellings. This article presents an evaluation of the advantage given to SAP ratings by the domestic installation of typical photovoltaic (PV) and solar domestic hot-water (SDHW) systems in the UK. Comparable PV and SDHW systems will also be simulated with more detailed modelling packages. Results suggest that calculation variances can exist between the SAP methodology and detailed simulation methods, especially for higher performance systems that deviate from the default efficiency parameters.

실험조건에 따른 임팩트 볼의 바닥충격음 변화 고찰

본 연구의 목적은 일본의 표준 중량충격원인 임팩트 볼을 국내의 표준중량충격원으로 도입시 바닥충격음 실험에 있어서 정확성에 대해 실험을 통해 알아보고자 했다. 이를 위하여 임팩트 볼을 이용하여 낙하 높이별, 가진위치를 바꾸어서, 수음점 높이에 대한 논의를 진행하였고, 임팩트 볼을 이용한 바닥충격음을 측정하고 이를 실제 충격원인 뛰는 충격음과 비교하여 실제 충격음과 가장 유사한 낙하 높이에 대한 검토를 실시하였다. 또한 일본 주택에서 주로 사용되고 있는 목구조와 국내 공동주택의 기본 구조인 콘크리트 구조에서의 바닥충격음 특성차이를 알아보기 위해 실험동에서 같은 조건으로 시험을 실시하여 시공재료 및 구법에 따른 차이를 알아보고자 하였다. 이에 대한 결과는 목구조에서는 낙하 높이가 10 cm에서 30 cm사이의 충격음이 실제 충격음과 비슷한 음압레벨을 갖는 것으로 나타났고 콘크리트 구조에서는 유사한 음압의 높이는 없었다. 또한 사람이 임팩트 볼을 운용하면서 표준낙하높이를 기준으로 상 하 10 cm 높이차로 생기는 오차는 역 A특성 값에서 약 1 dB이하 정도로 작은 오차를 나타내긴 하지만 우리나라에 표준 중량충격원으로 도입할 때에는 다양한 콘크리트 바닥구법에 따른 바닥충격음의 특성에 따른 적합한 임팩트 볼의 낙하 높이 및 측정 마이크로폰의 높이에 대한 고려는 신중히 하여야 한다. In Japan, bang machine has been considered to have problems about not only the impact force and frequency response which are different from the real impact sources such as children's jumping and running, but also damage in the wooden structure housing. Therefore, a new impactor for lower impact force to prevent demage in wooden structure housing was developed. The impact ball was adopted as the second standard impact source in JIS A 1418-2 and ISO 140-11. In the present study, floor impact sounds generated by impact ball with drop heights in four floors of mock-up building of Building Research Institute (BRI) similar to typical Japanese wooden structure housing were investigated and also compared to jumping sound. The results show that Impact ball sound dropped at 10 cm to 30 cm was most similar to jumping sound. And The impact sound levels at 250 and 500 Hz were more sensitive to drop height than other lower frequencies. The error that may occur from the difference of height of 10 cm up and down based on the standard drop height caused by the impact ball operated by human hands was approx. 1 dB or less only in its value of characteristic, but it must be carefully taken into Impact ball in the Korea Standard.

The effect of current thermomodernization projects on energy performance of multi-family residential buildings and perspectives for new regeneration projects: the case of a housing estate in Lublin

Managers of large housing estates whose stocks consist mainly of precast concrete plate buildings of 1970ies, due to their sheer size and technical condition far from being perfect, are especially concerned with searching for solutions that would reduce energy consumption. Thermal modernization projects provide an opportunity to adopt a holistic approach to the problem of obsolescence of this relatively new housing stock and to consider it in terms of urban regeneration. The paper describes the energy saving policies in Poland and results of pilot studies of Building Research Institute (ITB) aimed at defining optimal scope of thermomodernization of precast concrete plate housing. The paper investigates into the effects of thermomodernization of a particular, though typical, housing estate in Lublin in order to give grounds for future actions in the field of energy saving measures.

Modified Elastofiber Element for Steel Slender Column and Brace Modeling

An efficient beam element, the modified elastofiber (MEF) element, has been developed to capture the overall features of the elastic and inelastic responses of slender columns and braces under axial cyclic loading without unduly heavy discretization. It consists of three fiber segments, two at the member ends and one at midspan, with two elastic segments sandwiched in between. The segments are demarcated by two exterior nodes and four interior nodes. The fiber segments are divided into 20 fibers in the cross section that run the length of the segment. The fibers exhibit nonlinear axial stress-strain behavior akin to that observed in a standard tension test of a rod in the laboratory, with a linear elastic portion, a yield plateau, and a strain-hardening portion consisting of a segment of an ellipse. All the control points on the stress-strain law are user defined. The elastic buckling of a member is tracked by updating both exterior and interior nodal coordinates at each iteration of a time step and checking force equilibrium in the updated configuration. Inelastic postbuckling response is captured by fiber yielding, fracturing, and/or rupturing in the nonlinear segments. The key features of the element include the ability to model each member using a single element, easy incorporation of geometric imperfection, partial fixity support conditions, member susceptibility to fracture defined in a probabilistic manner, and fiber rupture leading to complete severing of the member. The element is calibrated to accurately predict the Euler critical buckling load of box and I sections with a wide range of slenderness ratios (L/r=40, 80, 120, 160, and 200) and support conditions (pinned-pinned, pinned-fixed, and fixed-fixed). Elastic postbuckling of the Koiter-Roorda L frame (tubes and I sections) with various member slenderness ratios (L/r=40, 80, 120, 160, and 200) is simulated and shown to compare well against second-order analytical approximations to the solution even when using a single-MEF element to model each leg of the frame. The inelastic behavior of struts under cyclic loading observed in the experiments of Black et al., Fell et al., and Tremblay et al. is accurately captured by single-MEF-element models. A FRAME3D model (using MEF elements for braces) of a full-scale six-story braced frame structure that was pseudodynamically tested at the Building Research Institute of Japan subjected to the 1978 Miyagi-Ken-Oki earthquake record is analyzed and shown to closely mimic the experimentally observed behavior.