If a property is in close proximity to an airport, motorway or in a busy inner-city location it is likely to be affected by high levels of environmental noise. The levels of external noise entering the home can be attributed to many factors; however one of the key factors is the performance of the windows installed in the property.
Define dB Levels Required
Improved sound reduction in a room is often achieved with high-performance acoustic glazing. The very best acoustic performance is achieved where glazing panes are made from laminated glass which can vary in thicknesses. It is important to quantify the required acoustic performance required and ideally, a sound engineer should be consulted to help in this assessment. Once you have defined the reduction in noise you are looking for, this needs to be matched to a glass type that will offer the required performance. Your window manufacturer should have data on the glasses which are available.
Highly experienced Bereco staff are on hand to discuss acoustic glazing options and offer guidance on the glass types we can offer to suit individual projects.
Manufacturing Capabilities
Often overlooked at this stage manufacturing capabilities is a crucial consideration for the window type you currently have or want. Manufacturers of windows have many different designs, which can often only accommodate double glazed units up to a certain thickness. There is little point in having a glazed unit chosen for its acoustic value if the unit size cannot be accommodated within the product you require.
Most manufacturers currently are able to accommodate 24mm double glazed units into their profiles although acoustic glass can be a lot thicker. The use of laminated panes of glass, which offers the best acoustic performance often means this thickness can be up to 36mm. Many manufacturers would be unable to fit such wide glazing units within their window types, particularly on the more traditional types of windows such as sash windows.
The skilled workmanship and technical advances in our factories mean we have the manufacturing capabilities necessary to produce sash windows with profiles up to the 36mm necessary to accommodate the most superior acoustic glazing. Our Sliding Sash designs can achieve decibel ratings of up to 45 dB.
Window Performance
The overall performance of the window also has a significant impact on acoustic performance and is often overlooked. There is little point in investing in acoustic glass that it is then fitted into a window that has poor performance characteristics. Any gaps between sashes, however small, will allow the noise to penetrate regardless of the glass type used. Windows in general should have independent testing from a third party independent body such as BM TRADA or BSI. Look for the windows which have severe weather ratings which are independently tested and accredited in high-performance schemes such as the BM TRADA Q Mark scheme.
Bereco’s acoustic sash windows have achieved outstanding weather testing results and we are one of only 3 manufacturers in the UK covered by the BM TRADA Q Mark High Performance Window Scheme – link
Ventilation
It is also important to consider how the use of trickle vents can impact a windows’ acoustic performance. Whilst trickle vents are published with acoustic values this can often be misleading due to the criteria on which they are valued. Where high acoustic performance is required trickle vents should be avoided as they will have a detrimental effect. Acoustic block ventilators are large, aesthetically unattractive and often cannot be accommodated in window designs.
In the event of an acoustic glazing requirement, we advise alternative means of airflow via mechanical extraction rather than the use of Trickle Vents.