University campus will way exceed Part L — without renewable energy
A new university campus in Wales shows how Part L can be comfortably exceeded without heavy investment in low- and zero-carbon technologies.
The design for a new city-centre campus for the University of Wales Newport has achieved a 14.5% improvement on Part L and a BREEAM ‘Excellent’ rating without heavy investment in low- or zero-carbon technologies. As well as carrying out an initial BREEAM and sustainability assessment, Faber Maunsell | AECOM designed M&E services, fire engineering, acoustics, ICT and advanced security.
This £35 million campus is due to open in 2010 and is the first phase of an intended £50 million 2-phase development for the university with partnership funding from Newport City Council and the Welsh Assembly Government (WAG). Sustainability is a key consideration underpinning the whole design, and a condition of the funding from the WAG was that the campus building should achieve a BREEAM ‘Excellent’ rating.
‘We took the BREEAM issue on board right from the start,’ said Faber Maunsell | AECOM project director Chris Lynn. ‘On some projects the BREEAM assessor can be rather passive, with a tendency not to get too involved in some of the key design decision making. ‘We took a very different view and involved our in-house sustainability consultants from day one, who regularly provided input to the design process. They were instrumental in influencing the conceptual thinking of the design team and held workshops to communicate the key elements for consideration. In this way sustainability was always a high agenda item and integral to every design decision.’
There was also an aspiration to exceed the requirements of the current Building Regulations Part L by at least 10%. In the event, the design has achieved a 14.5% improvement through simplicity of design, avoiding the need for renewable energy sources to meet the targets.
‘There are some projects where clients wish to include renewables as a visual token gesture, even though they may bring very little real practical added value,’ Chris Lynn explains. ‘In contrast, the university took a very honest view and was adamant that renewables should only be included if they offered real added value and benefits to the project. The simplicity and effectiveness of the integrated design solutions negated the need for renewables. However, the design does include some provision for future retrofitting of renewables at a later date, if required.’
It was clear to the designers from the computer modelling that a simple low-energy ventilation system would be one of the key elements in achieving the required energy performance, whilst helping to reduce potential maintenance cost — this being a key consideration for the estates team. However, the proximity of a main road with recorded noise levels of up to 80 dB(A) obviated the use of natural ventilation as sound levels in many teaching spaces were predicted to reach around 50 dB(A) during the day with open windows.
‘Because of these influences we’ve opted for displacement-ventilation in teaching spaces using the floor space as a supply air plenum and introducing the supply air through swirl diffusers at 19°C and low velocity to avoid draughts. In lecture theatres the diffusers are located under the seating,’ explained project manager Kevin Searle. ‘Air is extracted at high level, and heat is recovered at the air-handling units using a number of energy-saving measures including, for example, a thermal wheel.
‘There will be some mechanical cooling in areas with high IT usage and in the sound studios. Ceiling heights were kept to an optimum level for cost reasons, which prevented the use of chilled beams so, where necessary, we will be cooling supply air from the air-handling units supplying these areas.’
To further optimise the performance of the ventilation system, spaces with variable occupancy will have carbon-dioxide sensors to provide demand-controlled ventilation. The design team also developed an understanding of the projected use of the various spaces to achieve further fine tuning.
‘We worked very closely with the university to understand the usage and occupancy patterns of the various spaces and to set permissible peak temperatures based on this information,’ recalled mechanical engineer Sarah Gealy. ‘This enabled us to raise set point temperatures in areas where temperature wasn’t critical and in teaching spaces that will not be in use during the summer months. In other areas, such as lecture theatres, temperature was considered critical, and strict limitations were placed on peak temperatures.’
Heating will be provided by gas-fired condensing boilers serving a combination of trench heating and low-level radiators. Using flow/return temperatures of 65/45°C will provide good condensing and optimise the efficiency of the heating plant.
Thanks to BDP's innovative design approach the internal spaces will enjoy the benefits of high levels of natural daylight, and the lighting design takes full advantage of this. Lighting in teaching spaces uses dimmable T5 linear fluorescent light sources, which are controlled in relation to daylight levels and occupancy to minimise electricity consumption. Where decorative lighting effects are required, light-emitting diodes (LEDs) will provide accent lighting, again with minimum energy consumption.
‘Budgetary constraints meant that we had to give very careful thought to the lighting system,’ explained Kevin Searle. ‘Working with BDP we have created layers of light using a minimum number of fittings, providing a high-class feeling at a relatively low cost — a happy compromise.’
Except for some initial enabling works, the main works began onsite in December 2008 and is set to deliver not just a new campus but an iconic landmark for Newport by 2010. Throughout the design phase there has been close collaboration between all team members, and with the client.
