An AT webinar supported by Geberit explores the value of optimising acoustic comfort within buildings.
Acoustics is a Cinderella of design. Look at an architect’s drawing and, however good it is, there will be little indication of how the space behaves acoustically. Yet sound (or, if we don’t like it, noise) is incredibly important. A YouGov study, sponsored by piping and sanitaryware designer and manufacturer Geberit, found that more than half of the 2000 UK-based respondents suffered from unwanted noise in their homes, and that 35 per cent of them said that this noise affected their sleep. In particular, 28 per cent said that they were regularly disturbed by bathroom sounds at night, and 19 per cent that they were regularly disturbed by flushing toilets, running taps or pipes and drains.
In association with
Webinar Participants
Dr Anthony Chilton
Senior partner, Max Fordham
Ben Burgess
Associate director, Buro Happold
Dr Oliver Wolff
Head of building physics, Geberit
Helen Sheldon
Associate, RBA Acoustics
Geberit’s state-of-the-art sound laboratory is used to investigate acoustic issues relating to bathroom design (ph: Michael Suter)
Understanding the issues
Speaking at Architecture Today’s ‘Noise Matters’ webinar Dr Oliver Wolff, head of building physics at Geberit, showed just how complex the issues are and how much knowledge his company has. He demonstrated, for instance that, while reducing the sound emitted from pipes is important, the first peak of sound occurs when flushing the WC before there is any water in the waste pipe – the sound then carries through the wall and into adjacent rooms. This kind of information is produced in the company’s sound laboratory, and Wolff showed the kind of forensic analysis that it can use to put problems right. Nevertheless, he stressed that the best way to deal with noise problems is to consider them as early as possible in the design process, and this was a common theme throughout the discussion.
Acoustic considerations for housing
Helen Sheldon, an associate at RBA Acoustics, talked about the acoustic design of residential buildings. There is no simple answer, she said, to the question ‘How loud is too loud?’ since it depends on individual preferences, and also on the time of day and on activities. There is a pressure to redevelop brown-field sites, to build close to transport links and create a sense of community. The down-side of this, she said, can be noise from roads and railways, from bars and from gyms that are part of a development. Careful design is needed if we are not to tip over from a sense of a vibrant place to suffering from noise pollution.
Geberit’s new White Paper, ‘A Sound Solution’, calls for a radical rethink of UK regulations relating to sound insulation in the home
The importance of ‘auralisation’
Dr Anthony Chilton, senior partner at Max Fordham LLP, said that we don’t always go for the best acoustic answer because we have to balance acoustics against cost, the need for fresh air and against environmental issues, such as the embodied carbon of the building. The best way to define what you want to achieve, he said, is to ‘take a wellbeing-based approach’. A space should support the occupants’ ability to perform a task; it should give them a sense of autonomy and it should make them feel comfortable.
Defining this is essential he said. One important aid can be ‘auralisation’– the ability to show how a building sounds, as opposed to a visualisation, which shows how it will look. One of the examples that Chilton discussed was Burridge Gardens, a residential scheme designed by Hawkins Brown that backs onto the busy railway lines near Clapham Junction, south London.
Acoustically-optimised Geberit Duofix prewall installation frame with concealed cistern and Geberit iCon wall-hung WC
By working with the architects on the position of the buildings, Chilton was able to help them use one building to shield the others from sound. On this one building, the engineer worked with the architect to help meet the client’s wish to avoid a sealed facade with mechanical ventilation. Instead, it used noise-cancelling vents that can provide adequate ventilation on all but the very hottest days. Chilton also discussed open-plan offices which can he said, ‘look very similar, but be different acoustically’ because of the nature of the tasks. ‘You need to understand what people are doing in the space,’ he said.
Buro Happold is employing a ‘box within a box’ strategy for acoustic isolation at the BBC Symphony Orchestra’s new Stratford home (CGI: Allies & Morrison)
Key considerations for better acoustic design
Ben Burgess, associate director at Buro Happold, said that there were six key factors in acoustic design. They were: noise break in from, for example, transport; noise break out from activities in the building or plant that could affect the neighbours; the level of sound insulation between spaces; room acoustics and reverberation control; internal service noise; and the design of AV and sound systems. ‘As a take home,’ he said, ‘you can treat this like a tick list. If the design has information on all these elements, you can be confident that it is comprehensive.’
Buro Happold’s ‘box in a box’ concept details for the BBC Symphony Orchestra building in Stratford
He also talked about the new home for the BBC Symphony Orchestra on the former Olympic Park site. A ‘box in box’ design protects classical performances from both external noise and from rehearsals and performances of rock music that will happen immediately below. In addition, the architect, Allies & Morrison, wanted part of the building to cantilever four metres, which was only achievable with a lighter structure, which was more acoustically challenging. Buro Happold achieved this with a change in structure and a composite timber floating floor. As Burgess concluded, ‘Engaging acoustic engineers really is useful. They can pull off fantastic results from unusual processes.’ Sound advice, indeed.
