Birmingham Control Tower

Birmingham Control Tower


For the air traffic controllers at Birmingham Airport, concentration is critical to ensuring the safety of the hundreds of passenger jets that take off and land every day. Studies show office workers lose concentration when noise levels hit 55dB; however, the sound of just one medium-sized aircraft descending at 1,000ft is 70dB.


With this in mind, noise reduction was an essential factor in the specification of the insulation for the 105ft air traffic control tower. The airport’s developers consulted Knauf Insulation’s Technical Support Team for advice. The Technical Support Team recommended Rocksilk® RainScreen Slab, a non-combustible Rock Mineral Wool insulation designed for use in high-rise rainscreen façade systems.

Mineral Wool insulation has superior acoustic performance because of its open structure, which traps sound between the individual strands and turns it into heat energy.

Rocksilk® RainScreen Slab is quick and easy to install and adapts to minor imperfections in the substrate. Slabs are flexible and knit together eliminating air gaps for maximum acoustic and thermal performance, making it perfect for use on the curved walls of the funnel shaped control tower. 

The same level of acoustic performance could not have been achieved with rigid foam boards, which have closed cell structures that offer virtually no sound absorption. Rigid foam boards are also more prone to air gaps, reducing acoustic performance further.

As well as excellent acoustic and thermal performance, Rocksilk® RainScreen Slab is non-combustible with Euroclass A1 reaction to fire classification. This means it will not contribute to the spread or development of fire should it occur.

Another factor in the specification of Rocksilk® RainScreen Slab was sustainability. It is manufactured with ECOSE® Technology, Knauf Insulation’s unique bio-based binder, which contains no added formaldehyde or phenol. It is made from natural raw materials that are rapidly renewable, and is 70% less energy-intensive to manufacture than traditional binder, so it is more environmentally friendly. Products made with ECOSE® Technology generate low levels of dust and VOCs, and have been awarded the Eurofins Gold Certificate for Indoor Air Comfort.

Thanks to Rocksilk® RainScreen Slab the air traffic controllers at Birmingham Airport can enjoy a quieter, warmer, safer and more sustainable workplace.


Acoustic protection, energy performance, fire safety and sustainability were all crucial factors taken into account during the design of the air traffic control tower and so all materials specified with the project needed to meet these multiple requirements. We are extremely pleased with the building.
Will Heynes, Birmingham Airport’s Development Director
Client Birmingham City Airport
PROJECT: Birmingham Control Tower
MAIN CONTRACTOR: Simco External Framing Solutions Ltd