Newcastle College required replacement blinds for a large roofed area. The construction of metal and glass allied to the pitch of the pitch of the roof could have almost been designed as a sound reverberation chamber. The light needed controlling; the fabric had to be robust and durable with a very heavy bottom bar being specified on a blind of 6.0 m drop and the acoustics had to be addressed.
Nearly 400sqm of glazing, were shaded with the installation of 36 motorised blinds, each 2.0 m wide x 6.0 m drop using the Acoustis 50 fabric. The fabric colour chosen, 0730 (Slate Grey), providing excellent light control with its Tv (visible transmittance) level of 5% meaning that 95% of the light is prevented from entering the chamber. One fabric supplying both light control and acoustic comfort, change the colour and the same fabric offers acoustic comfort with improved heat control, the fabric in colour white having a Solar reflectance of over 70%.
So what is acoustic comfort? You all know the problem, a busy restaurant, a happy drinks party, you are having difficulty understanding somebody only a few feet away, so you speak louder, they speak louder, everybody speaks louder and nobody can hear a flipping thing. Someone shouts, ‘the acoustics are rubbish in here’ and everybody nods. But what can be done about it?
The problem is not noise volume; it is the lack of clarity to the sound. Referred to by acousticians as speech intelligibility or sound reverberation, unintelligibility is caused by sound rebounding from surfaces of differing distances away from the source, their reflections, or echoes, taking varying lengths of time to return. A single sound becomes a chain, multi syllables and multi-words becoming a constant stream of sound. Multiply that up by a number of people speaking at the same time and there is your problem.
How do you solve it? Remove or reduce the reflections. Hard smooth wall and ceiling surfaces part of the problem – glass one of the biggest culprits.
If you could cover the glass with something that absorbs the sound, but is thin and capable of being quickly removed and put away discreetly when not required.
If you could cover the glass with something that also gives good light control, removing glare and provide daytime privacy.
If only there was a fabric that absorbs the sound, is thin, gives daytime privacy and good heat control.
There is, the Mermet Acoustis 50, an acoustically absorbent fabric, less than 1 mm thick, with both exceptional fire rating and stability.
Acoustic absorbance is a sought after benefit in many instances, but acoustical transparency can be required in others. The interiors industry regularly seek a fabric to cover walls or ceilings that is acoustically transparent in order that acoustically absorbent foams hidden behind them can still work – similarly home cinemas and screening rooms often wish to hide loudspeakers within the wall without muffling the sound. The further requirements of fabrics in installations such as these being dimensional stability, allowing the fabric to be pulled taught into position without sagging over time, top level fire ratings along with an attractive easy to clean finish. The Mermet Screen Vision and Satine fabrics are both used in these respects, in the case of the Sv 10% in some considerable quantity.
Key to Mermet fabric use, be it for acoustic absorbance, transparency or another of its myriad other features, is the glass fibre core to the yarn. Mermet have been weaving in glass fibre for over 60 years, with coated yarns for the solar shading industry for over 40 years. The glass fibre cored yarn does not stretch, being made from sand it does not burn. These features facilitating the weaving of wide fabrics, to over 3.0 m, that do not stretch, do not move, lie flat, do not burn. All features required of interior fabrics particularly in the public sectors, be they for shading, tensile structures or large format printing/signage.
Manufacturing the yarn as well as weaving the fabric gives Mermet the control and expertise to engineer features into the fabrics, the yarn coating carrying UV stabilisers, additional fire retardation elements as well as colour pigment. This means Mermet understand and can control solar reflectance, transmission and absorption. With some of the latest coatings the same attention can be directed at thermal resistance and transmittance. All properties being engineered into aesthetically attractive, workshop friendly, durable and therefore more sustainable fabrics.
The Satine, Screen Vision and Acoustis 50 fabrics referred to are just three of nearly 20 fabrics in the current 2015-18 collection, so many more fabrics, more choice and much more performance.