Energy Efficient Ventilation In Dwellings

GPG268

Energy efficient ventilation in dwellings – a guide for specifiers

Contents

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Introduction About this guide Building regulations and ventilation Why ventilate? The principles of ventilation Energy efficiency savings Improving airtightness Ventilation system design Installation issues Ventilation systems in dwellings Energy Saving Trust standards for new housing Applicationfor refurbishment Passive stack ventilation (PSV) Description Control Installation Maintenance and cleaning Criteria for establishing energy efficiency of passive stack ventilation Intermittent extract fans and background ventilators Description Control Installation Maintenance and cleaning Criteria for establishing energy efficiency of intermittent extract fans

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Single room heat recovery ventilators (SRHRVs) Description Control Installation Maintenance and cleaning Criteria for establishing energy efficiency of single room heat recovery ventilators Mechanical extract ventilation (MEV) Description Controls Installation Maintenance and cleaning Criteria for establishing energy efficiency of mechanical extract ventilation (MEV)14 14 14 14 14 14 15 15 15 15 15 15

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10 Whole house mechanical ventilation with heat recovery (MVHR) Description Control Installation Maintenance and cleaning Criteria for establishing energy efficiency of whole house mechanical ventilation with heat recovery 11 Other systems – positive input ventilation (PIV) Description Control Installation Maintenance References

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This publication has been revised with the assistance of the technical committees of the Residential Ventilation Association and The Electrical Heating and Ventilation Association.



Energy efficient ventilation in dwellings – a guide for specifiers (2006 edition)

1 Introduction

All dwellings need a supply of fresh air,not just for the health and comfort of the occupants, but also to control condensation, remove pollutants, and to ensure the safe and efficient operation of some combustion appliances. The amount of fresh air should match the needs of the dwelling and the people living within it. To achieve an energy efficient standard of ventilation requires consideration of both the building fabric and theefficiency of the ventilation system. Whether designs for new or existing buildings are under consideration, ventilation should be thought of as part of an integrated design approach for achieving energy efficiency. Thermal insulation, heating systems and controls, and householder advice are some other important aspects to consider during the design process. Home energy use is responsible for 27 percent of UK carbon dioxide (CO2) emissions. (CO2 is one of the main gases that contribute to climate change.) By following the Energy Saving Trust’s best practice standards, new build and refurbished housing will be more energy efficient – reducing these emissions, and saving energy and money, as well as safeguarding the environment. Traditionally, many UK dwellings have relied on natural airinfiltration to provide ventilation. This can result in excessive ventilation rates that increase energy consumption for space heating, and cause discomfort to occupants because of cold draughts. Energy loss due to ventilation accounts for approximately a fifth of space-heating energy demand in an older poorly insulated dwelling. In a new energy efficient house the high insulation levels mean that theproportion of space-heating demand due to ventilation increases to around a third. Equally, natural air infiltration alone can result, at times, in too little ventilation. This leads to poor indoor air quality and other, more readily visible impacts such as condensation and mould on indoor surfaces. The objective of a good ventilation strategy is, therefore, to provide a balance between energy...