Probably the single most important issue facing the Ventilation industry today is energy efficiency and carbon reduction and housebuilders everywhere are looking for cost effective means of achieving the best possible ratings which comply with required standards.  Ian Davis, Technical and Quality Manager at Burton-on-Trent’s Vortice Ltd explains some of the key issues.

Emission Rates are expressed as the mass of carbon dioxide in kilograms emitted per square metre of floor area per year as a result of the provision of heating, cooling, hot water, ventilation and lighting, assuming a standardised household.  The ADL was issued by what is now known as the Department for Communities and Local Government as part of the Government’s drive to improve our environmental credentials.  The “Code for Sustainable Homes” followed this and sets out six target levels for improvement on the ADL requirements; called the “sustainability rating system”.

Level 4 of the code is defined by the Energy Saving Trust’s (EST) “Best Practice” standard for energy efficiency, and represents a 44% improvement over ADL, level 6 calls for ZERO Carbon Emissions.  All publicly funded Social Housing new build have had to achieve a minimum of level 3, however, soon level 4 compliance is necessary and because many developers build for the social sector, they have to provide dwellings to this standard - the Dwelling Emission Rate must be a minimum of 44% lower than the Target Emission Rate.

So, if a theoretical dwelling had a Target Emission Rate of 24 kilograms of carbon dioxide emitted per square metre of floor area per year, then in order to achieve Level 4, the Dwelling Emission Rate must be no more than 13.44 kg per year.  “Best Practice” is not only about ventilation requirements and compliance may be demonstrated also by taking into account additional factors such as U-values, air permeability and lighting in order to achieve improvements on CO2 emission rates.  However, the EST Demonstrating Compliance Best Practice (2006 edition) outlines ‘Best Practice’ compliance to ensure good construction quality and continuing performance of the dwelling.  

These construction standards are required because compliance with Best Practice could otherwise be achieved for example, by specifying a ‘wood stove’ in a very poorly constructed dwelling.    The EST’s document GPG268 Energy Efficient Ventilation in Dwellings – A Guide for Specifiers details the ventilation requirements for compliance with the “Good Practice” and “Best Practice” performance standards.

The “Best Practice” performance standard represents a readily available higher standard and if an improved ventilation system is chosen in order to meet the standard, the ventilation options are limited to continuously running extract only fans (MEV or continuously running fans) and MVHR (ADF systems 3 & 4, respectively).  Compliance to these criteria is demonstrated by having product tested to Standard Assessment Procedure (SAP) Appendix Q (SAP Q) test procedures.

In general, a technology may use one form of energy (e.g. electricity) to achieve savings in another form of energy (e.g. gas or oil, in heating).  As a consequence continuously running extract only fans (MEV or single-room units) and MVHR are the only 2 forms of ventilation accepted to improve the efficiency calculation of the dwelling and the only 2 forms of ventilation that SAP Q can be applied to. 

The scheme is currently operated by the Building Research Establishment (BRE) and the Vortice Heat Recovery unit and Vortice Centralized Ventilation Extractor are two Vortice SAP Q Eligible products.  There is of course, no such thing as a SAP Q approved product, as the rating depends on so many other factors, but products designed to be eco-friendly may be Appendix Q Eligible.

The SAP Q Calculation Spreadsheet outputs energy saved and energy used data that the SAP Assessor then inputs into a SAP Q section of the SAP Worksheet. The SAP Worksheet then takes this information into account in calculating the Dwelling Emission Rate (DER).  (Of course it also takes many other factors into account, such as wall constructions, windows, lighting, etc.)  The SAP Assessor finally compares the calculated Dwelling Emission Rate (DER) with the Target Emission Rate (TER) to ensure that the required improvement over ADL (a 44% reduction if the dwelling is being built to the Code for Sustainable Homes Level 4) is reached.

Vortice is Europe’s leading ventilation and air-conditioning company and has launched a series of new eco-friendly products developed with the Code for Sustainable Homes.  

Vortice kicked off 2010 with a brand new smaller size heat recovery system launched at Eco-build in March.  The Vort HR200 follows on from the highly successful Vort Prometeo HR400 launched last year and used to great effect in many high profile developments in 2009.  Vort Prometeo HR400 is designed to the highest environmental standards, with a tremendous heat exchange efficiency of up to 92%. It has SAP Appendix Q eligibility when installed on a ground breaking Kitchen plus up to 8 additional wet rooms configuration.

The main benefit of the Vort HR200 is that the compact dimensions of the unit make it small enough to fit into a cupboard space; the unit is ideal for apartments and smaller housing units. The Vort HR200 is SAP Q Eligible and is suitable for a kitchen plus up to 3 additional wet rooms. 

Technical Manager Ian Davis said: “Nowadays market trend for new private and social dwellings is essentially focused on smaller houses and apartments, therefore causing a migration from bigger sized HRUs to smaller units.  The Vort HR200 is designed specifically for this market and, with the Code for Sustainable Homes embedded into its design ethos, it extracts from wet rooms and recovers heat for use elsewhere in the home.  Together with the other highly energy efficient ventilation products launched in 2009, the Vortice portfolio is incredibly strong on eco friendly fans and heat recovery systems taking us forward to a more carbon friendly future.”

Vortice also launched the Vort Notus (one fan for any room), the Vort Platt ES (ideal for apartments and small spaces), Vort Penta ES (continuous running extract fan for up to 6 rooms) and the Vort Leto MEV (available in hard wired and radio frequency remote versions) during 2009, all of which can be seen on the website www.vortice.ltd.uk

Content provided by Ian Davis Technical & Quality Manager of Vortice Ltd

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