BREEAM (Building Research Establishment Environmental Assessment Method) is a widely used method for assessing the sustainability of buildings in Europe. It focuses on ecological aspects and awards buildings points based on various sustainability criteria, including acoustic requirements. Acoustic measurements are an important part of BREEAM certification and contribute to the overall assessment of the building.
BREEAM (Building Research Establishment Environmental Assessment Method) is a sustainable development assessment method for planning, infrastructure and buildings. BREEAM certification is the most widely used method of building assessment in Europe. It places special emphasis on ecological aspects. BREEAM as a method of assessing buildings was created in Great Britain by the Building Research Establishment, or BRE. In the context of acoustics for designed buildings, appropriate changes are introduced that will allow to meet the BREEAM requirements, while for existing buildings, certain acoustic parameters are measured, which should not exceed the limits given in the requirements. Acoustic measurements are one of the elements of full building certification.
The certification requires buildings to meet the requirements in 10 categories: management, water, energy, transport, health and well-being, resources, waste, ecology, pollution, materials, recycling and innovation. Points with appropriate weights are awarded for meeting these requirements. The sum of these points determines the final score. Additionally, points can be earned for custom solutions that make the building more environmentally friendly in the above categories.
The BREEAM certificate significantly increases the value of the property. Certification is a guarantee of creating an energy-efficient, environmentally safe and comfortable building for residents or users. If the building has a BREEAM certificate, you can be sure that many high-class experts worked on its design. In addition, certified buildings are ecological and energy-efficient.
As part of the certification, you can get one of 6 grades. The best of them for a result above 85% is “Outstanding”, the next one for a score above 70% is “Excellent”, above 55% we get “Very good”, above 45% “Good”, above 30% “Pass”, and for values less than 30% buildings are assessed as “Unclassified”. The certification categories have criteria that must be met and for which the building does not receive points.
BREEAM certification applies to buildings in the design phase, buildings under renovation, districts in the planning phase and existing buildings. BREEAM therefore includes several possible schemes. Each of these schemes is provided with a separate document. BREEAM International New Construction 2016 applies to buildings under design, BREEAM International Refurbishment & Fit-Out 2015 to buildings under refurbishment, BREEAM Communities 2012 to districts, and BREEAM International In-Use to existing buildings. Depending on the building that is certified, the appropriate BREEAM document must be adapted.
One of the parts of the BREEAM certification are the points that the building receives for meeting acoustic requirements. The first of these requirements is for BREEAM 2008 Pol 08 and for BREEAM 2013 Pol 05. This document concerns noise emitted into the environment from a certified building. The second document is Hea 13 (Breeam 2008) or Hea 5 (Breeam 2013). It is related to the reverberation time in rooms and the insulation between rooms in a certified building.
The BREEAM certification includes several critical points that each certified building must meet. One of these points is the record that says about the obligation to employ a qualified acoustician to prepare an acoustic project covering the most important aspects of acoustics in a given building and to meet the requirements related to acoustic parameters. Working with room acoustics at the design stage can bring many benefits. At this stage, it is possible to identify the sources of noise and react appropriately by using acoustic materials or other solutions.
The requirements that an acoustician must meet in BREEAM certification are specified in the document Hea 13/ Hea 5 – Acoustic Performance. An acoustician is defined as SQA (suitably qualified acoustician), i.e. a specialist who must have a higher education in the field of acoustics. In addition, a minimum of 3 years of experience in the last 5 years is required. The project can be prepared by an acoustician who does not meet the above requirements, but in this case it is necessary to approve the project by SQA.
BREEAM certification in the field of acoustics means meeting the appropriate requirements related to the noise level in office spaces, canteens, conference rooms and acoustically sensitive rooms. Additionally, for rooms that are to be fully certified, the sound insulation between acoustically sensitive rooms and other rooms must be measured. The requirements for room parameters are contained in the document Hea 13/Hea 05. Insulation measurements should be performed in accordance with ISO 16283. The levels of the equivalent sound level A LAeq,T should be measured, and these measurements should be performed in already built rooms, but without equipment. The noise assessment should be carried out in accordance with EN ISO 717-1:1996. Measurements should be taken for a period of 8 hours between 9:00 and 17:00, but this is not required if a short, representative period of time can be determined.
In the BREEAM International 2013 document, in the Pol 5/Pol 8 – Noise Attenuation section, there is information that an assessment of noise emissions to the environment should be carried out for areas sensitive to noise within 800 m of the building under examination. Such areas are primarily residential buildings, hospitals, schools, libraries and places of worship. The difference between the emitted sound level A and the background level should be less than 5 dB during the day and less than 3 dB at night. Daytime is defined as the period of time from 7:00 to 22:00, and nighttime is defined as the period of time from 22:00 to 7:00. In addition, for the purposes of Pol 05/08, it is also necessary to measure noise emissions to the environment in accordance with PN-ISO 1997-1:2006 or in accordance with British standards BS 4142 and BS 7445. If there are no external sound sources within the building, measurements can be omitted. Instead of measurements, the acoustics prepare a document confirming the absence of noise sources.
According to BREEAM certification, acoustically sensitive rooms are those in which privacy is important. Such rooms are offices, meeting rooms, consultation rooms, as well as study rooms and lecture halls. The designer of the building can decide whether a given room is acoustically sensitive.
Background noise measurement guidelines include noise from both internal and external sources. If the windows are to be opened in the room, the measurement should be taken with the windows open. There is no need to include noise from room equipment. The measurement should be performed in at least 4 rooms where we expect the highest noise levels. Measurements shorter than 5 minutes should not be performed, representative results can be obtained already for measurements for about 30 minutes. The insulation should be measured for 4 pairs of rooms most exposed to noise.
For rooms used for speech work, i.e. where speech intelligibility is important or for music playback, it is necessary to measure the reverberation time. Depending on the volume of the room, the reverberation time for speech should increase from 0.4 s for rooms with a volume of 50 m3, up to 1 s for rooms with a volume of 2000 m3, while the reverberation time for music should be from 1 s to 1.6 s. Lecture halls, recording studios and libraries have their own separate requirements. For the purpose of assessing these rooms, we measure the reverberation time for the middle frequencies. For lecture halls it should be below 0.8 s for small rooms (less than 50 people) and below 1 s for rooms where more than 50 people may be present. Recording studios should have a reverberation time between 0.6 and 1.2 seconds, while listening rooms should have a reverberation time below 0.5 seconds.
The background noise levels in a room, as permitted in BREEAM certification, are most stringent for lecture halls – below 35 dB noise level. Noise below 40 dB should be maintained in general purpose rooms and small office spaces, as well as in meeting rooms. The requirements for such rooms as open spaces, kitchens, restaurants and commercial areas are specified in the range of 40 to 55 dB.
In Poland, the SVANTEK Measurements Laboratory prepares projects, measurements and reports for BREEAM certification. Our acousticians meet SQA requirements and have the appropriate experience in measurements for BREEAM certification. Reports prepared for certification purposes are complete and meet all requirements.
