Building Performance Analysis & Strategy
Air tightness requirements in buildings are becoming increasingly demanding. Consequently it is crucial that airtight design principles and techniques are embedded in the design and construction process to ensure that the requisite airtightness levels are achieved at practical completion. We provide consultancy services that systematically work through architectural detailing and construction methods to reduce the likelihood of air leakage. During construction inspections and smoke survey can be undertaken to assess the quality of workmanship and highlight leakage paths. Interim air pressure testing with fans can also be undertaken to determine the air permeability result at a given stage in the construction process and inform the anticipated test result at practical completion.
Computational Fluid Dynamics (CFD) modelling is used in various situations within buildings to assess the effectiveness of ventilation strategies in achieving the desired air quality and indoor temperatures, either by natural means or forced convection. CFD is critical to assess the effectiveness of systems to achieve the desired air flow through zones. The modelling results inform the recommendations and guidance on thermal mass, equipment location and the optimal ventilation and mechanical services specification.
A microclimate analysis is used to ensure a development provides a comfortable outdoor environment through the control of climatic conditions on a micro scale. Multiple environmental factors can be modelled such as; temperature and thermal comfort, solar exposure and shadowing, air direction and speed, dust and noise pollution.
Condensation in building components occurs when warm moisture-laden air meets cold vapour-resistant surfaces. Condensation has two primary forms: surface condensation (visible on surface) and interstitial condensation (between construction layers and hidden). A good building envelope design will have systematically designed-out the risk of condensation by performing a Condensation Risk Analysis which would highlight the potential risk and verify that the proposed design solution has mitigated that risk.
Dynamic Condensation Risk Analysis using WUFI software provides a highly detailed and accurate evaluation of the risk of interstitial condensation, mould growth, frost risk and corrosion. This hygrothermal (the interactions between heat and moisture) analysis provides the basis for recommendations on material types and thicknesses, cavity dimensions and appropriate ventilation levels to achieve a best practice design standards such as EN 15026. This is now a requirement for all internally insulated external walls.
Daylight and Sunlight Impact Assessment & Right of Light, Interior Daylight Calculations and Glare Assessments
Daylight and Sunlight Impact assessment calculate the impact on the daylight levels on the existing neighbouring amenities (dwellings, non-domestic uses, gardes, open spaces) by proposed developments. The daylight impact is measured in terms of VSC, ASPH, No-sky line and daylight hours.
A right of light (ROL) may be acquired by ‘anyone who has had uninterrupted use of something over someone else’s land for 20 years without consent, openly and without threat, and without interruption for more than a year,’ according to RICS. Where development will have any impact on the light received by neighbouring properties then Right of Light must be considered. The Right of Light assessment calculates the book value compensation and highlights the options for dealing with the resulting ROL issues.
An Internal daylight analysis calculates the daylight levels and distribution of the daylight inside a room, which is key tool in the design of a building’s fenestration and form. As well as ensuring the building will receive the necessary levels of daylight and maximise occupant comfort, the analysis can be used to comply with the BREEAM or LEED daylighting credits.
Glare occurs when direct light is received on a screen and there is high contrast between the screen and the surrounding areas. The glare analysis highlights the areas where glare risk is high, evaluates the daylight glare probability (DGP) for different workstations in the space and provides recommendations to reduce the glare.
Energy Performance Certificates (EPCs) estimate the amount of energy a building will consume and are the ultimate output from Part L energy modelling. They are a legal requirement for domestic and non-domestic buildings under the Energy Performance of Buildings Directive. EPCs are typically produced at project practical completion and can also be produced for existing buildings. Low EPC ratings could in part be due to poor modelling, consequently Eight Associates always ensures that all calculations are done in full detail and not benchmarks to ensure the most accurate result.
Display Energy Certificates (DECs) reflect the actual real-life amount of energy a building has consumed over the past 12 months, based on an A to G scale. They are a legal requirement for all public buildings over 250 sq metres under the Energy Performance of Buildings Directive. They can be used a useful tool to compare how a building is performing in comparison to its predicted energy consumption, which is provided by the EPC.
Energy Assessments are the accompanying reports for planning applications for domestic and non-domestic buildings that demonstrates the proposed CO2 emissions reductions over Part L and the financial contribution for ‘zero carbon’ homes. The reports demonstrate compliance with national and local policies and regulations, thus establishing a scheme’s suitability for planning approval and ensuring the approved scheme can achieve it’s planning conditions at practical completion.
As part of an Energy Assessment an ‘LZC study’ assesses the feasibility of installing low and zero carbon energy technologies and quantifies the anticipated energy savings and CO2 emissions reductions. This report can be used to gain BREEAM credits and demonstrate compliance with planning requirements.
Energy modelling is required for domestic and non-domestic buildings to demonstrate compliance with Part L for Building Control and CO2 emissions targets for planning. It is an essential part of the design and construction process and aims to ensure buildings are designed with energy efficiency in mind. An LZC study assesses the feasibility of installing low and zero carbon energy technologies and quantifies the anticipated energy savings and CO2 emissions reductions. This report can be used to gain BREEAM credits and demonstrate compliance with planning requirements.
ASHRAE energy modelling uses the ASHRAE methodology (mainly used in North America, but also Australasia and the Middle East) to determine the likely energy consumption of a building and demonstrate compliance with the ASHRAE standard and achieve LEED energy modelling credits.
Energy management of existing and newly occupied buildings is essential to closing the performance gap whereby buildings use multiple times more energy in operation than predicted during design. This requires a thorough audit of the building’s systems and operational strategy, subsequently, an action plan can be implemented that reduces energy consumption whilst maintaining occupant satisfaction. Our energy management service is aligned with ISO 50001 standards and can be used to achieve ESOS compliance and ISO certification.
Eight Associates works with clients from all sectors to ensure long term environmental, social and economic sustainability objectives can be embedded into operations through robust policy, plans or project strategies. A clear understanding of our client’s aspirations is paramount to adopting feasible goals and we aim to assist with ease of integration into current practices.
Establishing sustainability objectives in large organisations requires detailed planning and careful implementation. Eight Associates works with key stakeholders within an organisation to establish their priorities and provides the technical knowledge of the environment to establish the trade-offs and likely outcomes of implementing the objectives. A bespoke appraisal criteria and toolkit can be produced by Eight Associates to allow the organisation to make decisions and prioritise their resources most effectively for the optimum sustainable outcome, or an ISO 20400 framework can be followed to achieve alignment with a global sustainability standard.
Indoor Environmental Quality (IEQ) comprises the fundamental metrics for a healthy indoor environment; air quality, lighting, thermal comfort, acoustics and ergonomics. All of these metrics impact on occupants so their enhancement improves human health, quality of life and reduce stress.
An Indoor Air Quality Plan is a typical document used plan and manage the air borne contaminants within buildings. Indoor Air Quality Plans contain advice on the levels of contaminants that are acceptable, measures for specifying materials with low emission levels, detailed procedures for flushing out buildings and advice on pre-completion testing to ensure acceptable levels have been met.
Staff costs are typically the largest single operating cost for a service business, strategies that improve employees’ health and productivity over the long run can have a large return on investment. Moreover, successful IEQ strategies can increase the resale value of a building and reduce liability for building owners. We undertake empirical measurements and sampling of all IEQ metrics on site, so we can verify the success of the design aspirations, and you can be confident that the results reflect exactly what was built.
Life Cycle Assessment (LCA) is a methodology for assessing the environmental impacts of a building or material from its origin through to disposal; its entire ‘lifecycle’. The environmental impacts from the consumption of resources and emissions of substances into the environment are quantified at each point in the lifecycle, which provides a holistic summary that can be used to inform decision making and provide an accurate comparison of options, crucially on a like for like basis.
LCA is now a fundamental part of the BREEAM process and is both a cost-effective and environmentally beneficial way to achieve the required credits for Excellent and Outstanding BREEAM ratings. LCA is also the tool to undertake Circularity studies and produce Circular Economy Statements to showcase the credentials of a building or construction system.
Post-Occupancy Evaluation (POE) is the process of obtaining feedback on a building’s performance in use. Eight Associates’ clients are increasingly recognising the value of POE as a tool to improve poor building performance and reduce impacts on running costs, and enhance occupant well-being and business efficiency. In some instances a POE can be conducted in one day, and involves analysis of energy consumption patterns and interviews with building occupants.
The UK government has made it mandatory (as of April 2019) for large businesses to report on their annual energy and carbon emissions. This is part of the government’s Clean Growth Strategy and aims to simplify the energy and carbon reporting landscape within the UK by implementing SECR. Businesses will need to comply with SECR if they meet at least two of the following criteria: more than 250 employees, over £36m in turnover or a balance sheet total greater than £18m. Organisations are exempt if they are in the public sector or use less than 40MWh over the reporting period.
The benefits of SECR include highlighting potential risks from volatile energy and commodity prices, identifying low-cost efficiency opportunities, and boosting sustainability credentials while tracking environmental KPIs. Eight Associates has extensive energy management expertise and works with relevant stakeholders to guide companies through the SECR process and identify operational cost savings.
Moisture must be controlled within buildings to prevent increased risks of condensation, damage to materials, reduced thermal conductivity of insulation and associated indoor air quality issues. Existing buildings, often constructed with moisture-permeable materials, must have appropriate strategies to avoid these risks. A structural moisture survey measures the current levels of moisture in a structure and aims to ascertain its cause. Subsequently, appropriate ventilation rates can be recommended to minimise the risks of structural moisture. This is a mandatory requirement for BREEAM Domestic Refurbishment and should be considered best practice for extensive refurbishment projects.
Karsten Tube testing may be required for existing building elements to calculate the water absorption (A-value) of materials e.g. brickwork which provides the essential data for WUFI condensation calculations to determine the interstitial condensation risk.
Thermal bridging analysis is often crucial in achieving Part L targets and is used to reduce the risk of condensation within the building fabric. Thermal bridging results where one or more elements meet that are more thermally conductive than the rest of the building envelope. These bridges can be designed-out through an iterative process of detailed psi-value calculations and careful architectural detailing.
Fenestration products have complex component geometries and material properties, which require the use of finite element analysis (FEA) in order to quantify the heat losses in thermal bridges such as frames, transoms and mullions. Calculating the heat losses of these products and systems determines the U-values than can be used for Part L energy modelling and the potential risk of surface condensation.
Dynamic simulation modelling is used to ascertain the risk of overheating and maximise occupant comfort within a building. The analysis aims to ‘design-out’ and reduce need for active cooling as much as practically possible. Guidance on U-values, thermal mass, airtightness, shading and the optimal ventilation and mechanical services strategy can be provided based on the modelling outputs.
Natural ventilation uses outside air movement and pressure differences to both passively cool and ventilate a building without the use of fans, which reduces installed plant costs and energy consumption. A successful natural ventilation strategy must also deliver high thermal comfort and adequate fresh air for the ventilated spaces, which requires dynamic thermal modelling to ascertain the level of effectiveness and the exact speed and volume of air flow.
Detailed calculations that determine gains, heat losses and other environmental conditions are often required to determine the heating and cooling load requirements for buildings and spaces. These data can then be used for sizing HVAC plant and ventilation rates as well as optimising the the building fabric and fenestration design.