Lignotrend: 20 years of acoustics with wood

By JMG Communications Published on Sunday, February 20, 2022 at 01:00

Photo credits : LIGNOTREND

It all started with a concrete problem. In production halls, it was difficult to hear even one's own words, as a Baden-Baden manufacturer, a global player in technical fabrics, in Murg, Germany, desperately discovered. At that time, the conventional metal architecture of the production halls struggled to provide acoustic solutions to the ambient noise of the machines. Even several attempts to improve the situation for employees, such as suspended elements under conventional sheet metal roofs, were never able to sufficiently reduce the noise level.

How a simple customer request became Lignotrend's core skill

Nearly 20 years ago, in 2001, a new production hall changed everything. The emergence of an acoustic innovation in wood provided an ideal solution. LIGNO® cross-laminated timber elements, equipped with a sound absorber, are integrated directly into the roof or ceiling construction elements. Once a simple pilot project, this has now become Lignotrend's core expertise. The specialist and supplier of cross-laminated timber products is celebrating its 30th anniversary this year.

Wood for structure and acoustics

Solving problems, developing details, recognizing new trends, and creating them—the Lignotrend company didn't choose its name for nothing. Since 1992, the cross-laminated timber specialist has been developing and manufacturing more and more innovative construction products.

During the construction of the new production hall in Murg in 2001, the conventional trapezoidal roof sheets were replaced by LIGNO® cross-laminated timber elements, which were laid on the metal structure as self-supporting elements. However, this unfinished roof panel would have required additional acoustic elements, unless the reinforced roof element already incorporated a sound-absorbing effect.

This idea from the designers immediately captivated and stimulated the creative minds at Lignotrend. The developers quickly succeeded in combining static and interior acoustics in a single element. At the factory, during the manufacturing of the elements, the absorbing layer is integrated between the slats, i.e., in the hollow spaces of the cross-laminated timber element. The underside of this layer is equipped with acoustic grooves. Thanks to the use of soft natural wood fibers instead of mineral absorption materials, the new element is made entirely of wood. LIGNO® Classic Acoustics was born.

The noise level has been significantly reduced

In laboratory acoustic efficiency tests, wood fiber proved to be the most effective sound absorber. With 3 m² of roof area made of classic LIGNO® Acoustique Q, the interior noise level in the fabric manufacturer's production hall was significantly reduced. While the specifications called for a reduction of 000 dB, it actually dropped by 3 dB. The noise level was thus reduced by a third.

This success story quickly gained traction. Shortly after this first project, the architects at Gerkan, Marg & Partner used the same system for two exhibition halls in Friedrichshafen. These projects demonstrated that a timber acoustic solution not only reduced noise levels but also optimized the sound quality of the exhibition rooms. Integrated into the supporting structural element, the interior acoustics requirement was already addressed at the structural level. There was no longer any need for additional, time-consuming and expensive interior work.

Over the past twenty years, Lignotrend acoustic elements have been constantly improved. In addition to the classic profile on the static support element, there are now variants with a knotless design and a refined grooved appearance. These solutions bring a special aesthetic to rooms with low ceilings.

For a second integration or further reinforcement of interior acoustics, LIGNO® Acoustique light acoustic panels are now also available as cladding for walls or ceilings. Recently, designers have been able to freely configure the individual appearance and performance characteristics of the panels or supporting elements and thus meet all the requirements of the planned project.