Periodic Reporting for period 2 - papabuild (Advanced physical-acoustic and psycho-acoustic diagnostic methods for innovation in building acoustics)
Reporting period: 2018-02-01 to 2020-01-31
This is achieved by a methodology that consists of 5 work packages:
(WP1) Improving the diagnostic methods for objective assessment of physical properties of buildings elements (ISO140). Accurate measurements are needed in order to adequately assess and compare the performances of sound insulation elements. This is mainly challenging for low frequencies, due to the non-homogeneous distribution of the sound pressure levels in the sending and receiving room of a test facility. In this project, different measurement methods are compared and new ones are developed and validated.
(WP2) Involving subjective assessment of sound insulation to help propose a suitable single-number quantity (ISO 717). It is well known that due to physiological and psychological reasons, people's judgement of the sound insulation performance of a building element is more complex and depends on multiple aspects of the sound. Nevertheless, for the sake of pragmatical comparison of the sound insulation performance in practical situations, it is useful to have a single number rating for that performance. In this project. by performing a variety of listening tests, we are assessing the adequacy of the currently used single number ratings in terms of their consistency with people's subjective assessments, and we are trying to further fine-tune ratings for optimum adequacy.
(WP3) Enabling sustainable product innovation based on improvements achieved in diagnostic methods. Besides their acoustic insulation insulation performance, there are several other aspects of building elements that need to be taken into account during the product development. Innovations of products that are beneficial for some aspects of the performance can be harmful for other aspects. Also, improvements of product features are only sustainable if those improvements are also appreciated by their users. Therefore, in this work package, we take a helicopter view on multiple aspects of building insulation elements, in order to see which innovations are compatible with all aspects, as well as which ones have most societal value.
(WP4) Disseminating all relevant techniques and results via proper media and personal contacts to designers, architects, as well as ISO policy makers, so that the efforts are investments in this project find their way to society, improving the life of EU citizens.
Main result: Development and validation of objective methods for laboratory and in-situ field measurement of sound insulation.
In a first step, alternative measurement approaches with Laser Doppler Vibrometry (LDV) and accelerometers measurement methods have been tested and applied for investigating the influence of construction details and the workmanship on the sound insulation of light weight building elements. The application of the alternative measurement approaches using LDV and accelerometer measurements supported the development of a first approach of a prediction model for predicting the acoustical behaviour and the acoustical interaction of thermal insulation layers - External Thermal Insulation Composite Systems (ETICS) - connected to traditional heavy walls (brick wall with ETICS) as well as for double transparent skin facades (DTF). An extended series of measurements have been carried out with standard and the new alternative methods for the selection of sound insulation characteristics of wall constructions with different (practical relevant) dominant influence of specific construction details to be applied as basic filters for creating listening test stimuli (supporting WP 2 and basic findings for WP 3).
WP 2. Subjective assessment of sound insulation performance
Main result: a methodology for listening tests has been validated.
The measurement methodology was tested by a series of listening tests that have been designed within this project. Various sound (noise) stimuli were chosen, including stationary sound sources and time variant sound sources. A series of listening tests were conducted.
WP3. Sustainable product innovation
Main result: a questionnaire probing people’s relative valuation of acoustic aspects in their living environment was set up and distributed.
This information is crucial in order to sustainability dose and channel efforts and investments in building insulation improvement.
The joint measurement technology, using classical microphone methods, laser Doppler scanning vibrometry, and accelerometer grid measurements will allow for a fully reliable assessment of sound insulation properties of building elements from 50Hz to 5000Hz, covering the full relevant range of the audible part of the spectrum. The different approaches will have been cross-validated on the basis of masonry walls, wooden panel assemblies, External Thermal Insulation Composite Systems (ETICS) and wooden noise barriers.
WP2: Subjective assessment of sound insulation performance:
By the end of this project, we will have assessed, by performing listening tests, whether (improvements of) acoustic insulation features are audible. This will allow to verify if the efforts in innovation and materials are spent in the most sustainable way. The project will also have yielded a novel single number rating (SNR)‘Rmod’ that, according to listening tests and a to theoretical considerations, which has a very good correspondence with subjective Loudness perception, substantially better than other single number ratings such as Rw and Rliving.
WP3: Sustainable product innovation
Besides the degree of audibility of differences in acoustic insulation quality mentioned above, also the value as such that people give to acoustic comfort is of great importance when taking decisions concerning priorities in investments in R&D or when choosing between different products. In view of that, an important axis of the project concerns the development and implementation of a questionnaire, which tries to probe people’s priorities when judging their daily life comfort and when considering their priorities when moving to another place or when to deciding on renovation investments. The roll-out of this questionnaire, by sending an online link to the social network of people in the network and via the PAPABUILD website http://papabuild.eu/questionnaire/ is ongoing. By the end of the project, responses of a large number of people will be available, allowing to assess people's sensitivity to acoustic comfort in their overall comfort assessment. Also, an analysis will be available on the importance and compatibility of different aspects of requirements of building elements (acoustic, thermal, fire safety, material cost, recycling cost, ecological sustainability, ...) that relate to their sustainable design and production.