London Green Register bite size session, Thursday 13th October: Window Design and Acoustics

Posted by IT MACH

London Green Register bite size session, Thursday 13th October: Window Design and Acoustics

29th January 2018Eco Buildings, Low Energy, Sustainable Acoustics, Window Design

Find out how to take a green, forward thinking approach to all aspects of building acoustics including window design.

In this bite size session, Ze Nunes, founder of MACH Acoustics, has been invited to present some lessons learned from lecturing & studying at the University of Bath (MSc in Sustainable Architecture and Phd “In the Visualization of Sound”). Ze has recently published two hugely significant books ‘Sustainable Acoustics’ and ‘The Future of Windows’. Signed copies of both books will be available subject to printing dates being achieved.

MACH Acoustics recognises the importance of noise control through window design. Where simple traditional design limits the use of open windows, MACH have now developed a range of unique software tools to help overcome noise break-in in residential buildings, offices and schools to prove that open windows can be used in noisier environments than previously thought.

Ze will demonstrate how to take a green, forward thinking approach to all aspects of building acoustics including window design. Best practice, the latest data, as well as useful ‘sustainable rules of thumb‘ are included in this presentation as well as an introduction into MACH Acoustics’ Web Based Design Tools, showing how best to position a building on site, how to minimise levels of embodied energy and select partitions between rooms.

IOA Annual Conference – MACH Acoustics presents

29th January 2018Acoustic Design, FDTD modelling, Talks/ Conferences, Window Design

The annual Institute of Acoustics Conference was held on 5^th and 6^th September in Kenilworth and MACH Acoustics’ Chris Jones was honoured to be invited to speak and present his paper. Chris has been researching “STANDARDISING THE TESTING AND MODELLING METHODS OF PREDICTING THE SOUND REDUCTION THROUGH OPEN WINDOWS” and this was extremely well received.

The current approach is to simply use a 10 – 15 dB reduction across the open window. This does not account for the window type, open area or angle of incident sound. Whilst research has been conducted into these factors, the lack of a standard method of testing, modelling and quantifying the acoustic performance has prevented the uptake of an improved method by acoustic and facade engineers.

This paper builds upon the research of collaboration with MACH Acoustics and The University of Bath – Blanco, Nunes and Lo (2014) and Jones (2015) in summarising the challenges in quantifying the performance by considering existing test methodologies from British Standards and extensive laboratory testing by Napier University (2007).

The potential of using FEM and FDTD modelling as a tool of visualising and understanding sound propagation through an open window is summarised. 2D FDTD modelling by Jones (2015) has examined the effect of the window variables and the accuracy of simulations by recreating Napier University (2007) test data, before using this to propose the concept of a simple mathematical model.

Visualizing components of sound propagation through an open window

The aim of this paper is not to conclusively recommend a standardised method, but to present existing information and new research in a balanced manner that will inspire a discussion within the acoustics industry as to how such a method might be agreed.

Posted by IT MACH

Green Register Bite Size Session – The Future of Windows

29th January 2018Window Design

Bite-Size Session: The Future of Windows – a sustainable approach to acoustic design – Bristol

Find out how to take a green, forward thinking approach to all aspects of building acoustics including window design – this talk takes place on May 12th in Bristol and has been commissioned by the Green Register.

In this bite size session, Ze Nunes, founder of Bristol based MACH Acoustics will present some lessons learned from lecturing & studying at the University of Bath (MSc in Sustainable Architecture and Phd “In the Visualisation of Sound”). Ze has recently published two hugely significant books ‘Sustainable Acoustics’ and ‘The Future of Windows’. Signed copies of both books will be available subject to printing dates being achieved.

Bath University “The Hive” plays a part in The Future of Windows

29th January 2018Window Design

The HIVE is a £1 million ground-breaking building project designed to support research into construction materials and is the first building project being developed at the Building Research Park. A University of Bath initiative, the HIVE is a natural coupling for MACH Acoustics to work hand in hand with as MACH exploors and progresses its work on The Future of Windows.

Over the past months Andrew, Ze, Yang from MACH have investigated various facades and window configurations, taken measurements and surveys and used this for their research. As Andrew says of this recent work: “Without this real life situation to investigate bold concepts in a cost effective manor we would not be able to validate our new façade modelling techniques. This will in the future provide the confidence to our clients that we can provide a fast evolving and robust façade scheme design such to incorporate natural ventilation into more buildings on noisy sites”.

For further information about The Hive use the following link:

http://www.bath.ac.uk/research/centres/brp/

Posted by IT MACH

The Future of Windows

29th January 2018Natural Ventilation, Sustainable Acoustics, Window Design

When the Romans invented the glass window, they couldn’t have anticipated the environmental context and settings years later: Windows continue to let in light ages on, however undesirable levels of air and sound also intrude.

MACH Acoustics recognises the importance of noise control through window design. Where simple traditional design limits the use of open windows, we have now developed a range of unique software tools to help overcome noise break-in in residential buildings, offices and schools to prove that open windows can be used in noisier environments than previously thought.

Working with your design, we will improve the acoustic performance of open windows and provide the solution that will work best for your project. It could be as simple as an extended window frame, proven to reduce sound; external baffles; or changing the shape of the window itself.

Download our book for free from iTunes to read how our ground-breaking, software tools can show you the future of windows, and check out the video clip also below.

https://itunes.apple.com/us/author/mach-acoustics/id1041471077?mt=11
https://www.youtube.com/watch?v=0IzL8MpbtOs&feature=youtu.be#

Posted by IT MACH

Keep passing the Open Windows

29th January 2018Natural Ventilation, Window Design

Introduction

This Blog Post is taken from the latest MACH Acoustics book “The Acoustics of Open Windows” – Chapter “The Future of Windows”. This book can be downloaded as an iBook from: https://itunes.apple.com/gb/book/the-acoustics-of-open-windows/id1049860606?mt=13

This book publishes part of Ze Nunes’ ongoing PHD, on the subject of visualizing sound and air in low carbon buildings.

At MACH we see that natural ventilation is one of the strategies of choice for forward thinking clients interested in low-energy buildings. However environmental noise break-in can be an issue, resulting in clumsy acoustic attenuators or windows being kept shut.

MACH Acoustics recognizes the benefits of noise control through window design. The team at MACH has therefore developed unique modeling tools, assessing noise mitigation solutions based around improving the acoustic performance of open windows, such to overcome noise break-in issues to residential buildings, offices and schools.

Extended Window Frame

One of the key factors affecting the sound reduction of an open window, is its ability to screen sound, i.e. the harder it is to see the sound source through the opening of the window, the better its acoustic performance. Hence by simply extending the frame of the window, as shown, the sound reduction of a simple window can be enhanced. The next two slides illustrate this effect, with an interactive model showing the effects of extending the frame and a video providing a subjective illustration of this change.

Baffled Facades – Illustrations

An alternative way of enhancing the performance of an open window it is place a baffle over its opening. MACH Acoustics’ analytical tools and measurements facility can be used to determine the size and position of the baffle such to provide the required acoustic performance from an open window.

Posted by IT MACH

Noise free open windows…A tall story?

29th January 2018Acoustic Design, FDTD modelling, Window Design

A new build range of large residential projects within an Asian capital city (confidential) for the public sector fitted well with our commercial research and development. MACH’s uniqueness in this field facilitated the creation of a new in house software package, implementing Finite-Difference Time Domain (FDTD) mathematics. This software package allows us to model bespoke constructions on a project by project basis, such that solutions are new and innovative.

Sound Insulation of Open Windows and Balconies

Introduction

The use of purge ventilation to naturally ventilate a building, can provide a significant challenge in regards to external noise ingress through the façade and open windows. Typifying the burgeoning requirement for affordable and luxury city centre accommodation, our client wanted bespoke options for a number of confidential, high-rise residential,overseasprojects.

The challenge is providing noise control measures without the use of bulky attenuators, thermal dampers and ugly weather louvers. We pooled our experience in building acousticswith Dr Steve Lo, Senior Lecturer in Sustainable Environmental Engineering at the University of Bath, to investigate the potential of noise mitigation by balcony shaping and other façade design options, in order to screen open windows from external noise sources such as road traffic.

Acoustic Modelling of Noise Ingress and Mitigation

The FDTD software was mainly developed in-house, but also through two MSc projects being supervised by Dr GwenaelGabard and Dr FillipoFazi at the ISVR, funded by MACH Acoustics.

FDTD is similar to commercial Finite Element (FE) modelling but has the advantage that the sound pressure field can be animated over time, allowing the wave propagation to be visualized, measured and assessed. A visual representation is a strong advantage in understanding the reflection and diffraction around walls, windows, balconies and screens.

‘Quiet’ Balconies

Balconies exhibit interesting differences in sound propagation depending on the height and distance from the road.The linked model video belowshows the nature of sound reflections off the balcony façade and soffits, used to assess one of the towers within this development. Adjusting the shape and finishes of these surfaces has shown value in reducing noise ingress into the proposed residential accommodation.

Figure 1: FDTD video of road traffic noise propagating into balconies of a high rise residential building

From the above model, a more detailed view can be presented to show just a single flat/balcony. The images below show a standard single balcony, with a reflector then built from the soffit in the direction of the source (road traffic) to direct sound back away from the balcony.

Figure 2: FDTD model of a single balcony with (bottom) and without (top) a noise mitigating reflective panel