acoustics
Amending BB93 to suit new school designs
There has been a lot of talk about the replacement for Section 1 of BB93 amongst acousticians, soundproofing specialists, building control officers and the DfE, but this has yet to reach the ears of many in the construction industry says ELLIE MORRIS.
Building Regulations with regards to sound insulation, reverberation times and indoor ambient noise in schools. Broadly speaking, it covers insulation from external noise; insulation between rooms through floors, walls and partitions; and acoustic design of rooms for speech, music and for pupils with special hearing requirements.
B
The insulation aspect of BB93 deals exclusively with sound transmission and sets out clear standards for precisely how much noise might be allowed to penetrate a classroom or other learning environment. The acoustic design component of the regulations deals with the more complex issue of reverberation. Although distracting noise from external sources or adjoining rooms is problematic and must be addressed, reverberation is particularly detrimental to speech recognition and, therefore, a crucial factor in learning.
B93 was conceived as a means of satisfying requirements E4 of Approved Document E of the
New era So, precisely what was wrong with BB93? On the whole, nothing. That is, there were no flaws written into the regulations, nothing that could be strictly referred to as an error. It's just that the way in which schools were envisioned, designed and built back in 2003 is quite different from the way in which they are envisioned, designed and built now. Although there are many small amendments, there are four key changes: • The removal of reverberation data from the equation to calculate resistance to impact and airborne sound transmission. This is good news for anyone looking to control their budget as the previous equation factored in reverberation without taking into account the fact that said reverberation would be dealt with by the self-same regulations. This could easily result in over-engineered soundproofing measures, designed to combat a problem that would disappear once rooms were adequately treated with sound absorbent materials
• The reverberation time in sports halls has been relaxed from 1.5 seconds to 2 seconds, as it has been recognised that, although this is technically a learning environment, speech clarity is less of an educational factor. Again, the regulations as they stood were leading to over- engineered solutions • A more onerous standard is now in place for open plan areas in recognition of the fact that more and more actual teaching is carried out in these areas • Where pupils with Special Educational Needs are being taught, there is a requirement to treat a broader frequency range than just the mid-frequency that was covered in BB93. Research has demonstrated that low frequency noise creates difficulties for children with Special Educational Needs. Ellie Morris is technical support coordinator at CMS Danskin Acoustics.
www.cmsdanskin.co.uk educationdab.co.uk 53
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64 |
Page 65 |
Page 66 |
Page 67 |
Page 68 |
Page 69 |
Page 70 |
Page 71 |
Page 72 |
Page 73 |
Page 74 |
Page 75 |
Page 76 |
Page 77 |
Page 78 |
Page 79 |
Page 80 |
Page 81 |
Page 82 |
Page 83 |
Page 84