Meeting the low carbon building challenge
In a bid to meet Kyoto carbon targets the Government is continuing to roll out a raft of energy efficiency legislation. Since buildings are responsible for nearly 50% of the EU CO2 emissions, with much of this generated by energy hungry services, it is consultants that have been set the challenge of delivering low carbon buildings. Commercial buildings are responsible for around 13% of total carbon emissions in the UK and although they do not have as much of an impact as domestic property they still have a vital role to play in the struggle against climate change.
The key legislation designed to reduce building carbon emission is the Energy Performance of Buildings Directive (EPBD) which was introduced in January 2006 with a three-year implementation period. With EPBD Energy Performance Certificates (EPCs) being introduced from 6 April 2008, the industry has a clear responsibility to improve the energy efficiency of commercial buildings and reduce carbon emissions.
The theory is that EPCs will show the energy performance of a building by giving a rating of A-G in a similar way to electrical domestic appliances, where A is very efficient and G is inefficient. This will allow prospective buyers, tenants, owners, occupiers and purchasers to see information on the energy efficiency and carbon emissions of a building so they can consider this and fuel costs as part of their investment. In addition, an EPC is always accompanied by a recommendation report that lists cost effective and other measures (such as low and zero carbon generating systems) to improve the energy rating of the building.
Under the umbrella of the EPBD, the latest revisions to Building Regulations Part L and Part F has had a significant effect on the drive for better air quality, greater energy efficiency and the reduction of carbon emissions in commercial buildings.
The latest revision of Part L signalled a significant shift towards energy efficient buildings and set the standard for the maximum carbon dioxide emissions for whole buildings. This performance-based approach offers designers the flexibility to choose suitable solutions to allow for adequate means of ventilation for people in the building in line with Part F, and which are energy efficient, cost effective and practical.
Document F has also been influenced by the requirements of Document L illustrating an important shift towards energy efficient ventilation. This has pointed towards improving building standard assessment procedure (SAP) ratings with heat recovery devices, efficient types of fan motor or energy saving control devices in ventilation systems, and shows the joined-up thinking now underlying the Government’s Standard Assessment Procedure for the Energy Rating of Buildings, Document F and Document L. SAP 2006 represents a 20% improvement in energy efficiency over SAP 2002.
In many commercial buildings, particularly older ones, ventilation is achieved either by opening windows or from natural air infiltration from gaps in the building fabric, which can result in excessive ventilation rates. This increases energy consumption and causes discomfort to occupants due to cold draughts. Too much ventilation is wasteful of energy, but too little ventilation is detrimental to the health and well being of both the occupants and to the building itself. It is critical to the success of any commercial building to provide indoor air quality suitable for a productive working environment whilst using the minimum amount of energy possible, in line with the requirements of the EPBD, Part L and indeed Part F of the Building Regulations.
With many commercial properties being built today, the principle is to ‘build tight – ventilate right’, minimising uncontrolled air leakage through the building envelope and providing an adequate ventilation rate via a controlled system. Reducing air leakage is essential with new build properties being tightly built; optimising ventilation and heat recovery are the key to providing a comfortable environment.
Therefore, the way to achieve adequate ventilation with minimal waste of heat is to implement a well thought-out ventilation strategy that provides a proper balance between energy efficiency and indoor air quality. To implement such a strategy it is important for designers to take into consideration the technological advances that have been made in ventilation and to utilise such systems to help them achieve a workable balance.
Controlled mechanical ventilation using heat recovery is an energy efficient ventilation offering which deserves consideration if Government targets are to be achieved. While the emphasis is on providing filtered, fresher air and the extraction of stale air and allergens to keep occupants healthy, there is also a clear focus on energy saving. Heat recovery systems provide a real means of achieving both the air flow requirements for human comfort in Part F and the energy efficiency requirements of Part L with full controllability, and the ability to recover as much as 95% of heat from a ventilated room. In fact, changes to Part L and Part F of the Building Regulations conspire to make central extract or whole-building heat recovery the preferred ventilation low carbon solution in the new-build market place.
Never before has it been as important to balance the requirements of ventilation and energy efficiency. It’s at this point that leading players, like Vent-Axia, have an important role to play. That’s why we have introduced a dedicated and comprehensive Vent-Axia Lo-Carbon ventilation range supported by unrivalled access to extensive technical advice, design and ventilation applications expertise. The VA Knowledge Bank, as it’s collectively known, exists to act as a low carbon ventilation resource for professionals within the building services industry, allowing them to easily access information on how to reduce energy consumption and cut emissions on a diverse range of projects.
At Vent-Axia we have developed a Lo-Carbon ventilation range to ensure full compliance to Building Regulations. Alongside commercial fans, it also includes residential fans, heat recovery systems, air handing units and the award-winning Sentinel on-demand ventilation systems which provides impressive energy saving performance in schools, theatres, offices and public building applications. Lo-Carbon ventilation is therefore relevant for all types of commercial projects as well as the increasingly popular mixed-use developments. Throughout this extensive range we have calculated not just the energy savings that can be made when comparing these high efficiency products to ordinary ventilation units but also the carbon savings that can be achieved based on typical usage.
On-demand ventilation systems, such as Vent-Axia’s Sentinel, are another key component in meeting low carbon targets and complying with the EPBD. Designed to meet modern building management control principles, this type of system responds to the exact ventilation requirements of a room at any one time, providing the right level of supply or extract only when required. Incoming fresh air is cleaned and filtered, and an optional heat recovery capability within the system allows Sentinel to recover over 80% of heat in winter that would otherwise be wasted. System design also cuts out outside noise distractions, heat losses and other pollutants that typically come with opening windows.
Vent Axia is committed to low carbon ventilation solutions and investing in the VA Knowledge Bank will be rewarded with specific low carbon knowledge and solutions to help ensure quick, easy and reliable ventilation specification. It all adds up to an ongoing drive for modern, cost effective and energy efficient air management solutions to provide indoor air quality to meet the needs of the marketplace and the requirements of legislation.