Natural strength

Durable acoustic cladding of ceilings and walls

Troldtekt cement-bonded wood wool is a rugged and durable material. The setting and curing process transforms the cement in the panels into concrete and gives the material its strength. The natural properties of the wood make the material breathable and permit diffusion. Troldtekt panels are suitable for screw installation and are also easy to work with and cut.


Troldtekt panels can absorb and release moisture and are therefore ideal for ceiling and wall cladding in wet rooms, such as bathrooms and swimming pool centres. Troldtekt panels can also be used outdoors, for example under overhangs. The material cannot rot and does not provide a breeding ground for fungi or other microorganisms.

Stable shape

Troldtekt panels have an extremely stable shape and retain their flatnes – even in moist environments. There is no warping over time. If the air humidity in a room changes by one percentage point, the panel dimensions only change by 0.005 per cent.

Download test report regarding moisture deformation.

Troldtekt acoustic panels withstand moisture and are therefore very suitable as acoustic ceiling and wall cladding in, for example, swimming pools

Ball impact certification

Troldtekt is ball impact tested in accordance with ‘Prüfung der Ballwurfsicherheit, DIN 18032 Teil 3, Sportshallen für Turnen und Spiele’ (requirements and testing of ball impact safety, DIN 18032, Part 3, sports facilities).

A wide range of constructions with Troldtekt are testet and approved for application as wall and ceiling in sports facilities and gyms where it is exposed to considerable impact when, for example, a handball strikes at high speed.

For further information about test method and certificates, please contact our local distributor


Natural strength
Troldtekt, Harboøre Sports Centre

Ceiling and wall cladding in sports facilities and gymnasiums are exposed to stress from ball impacts.

In Germany, documentation is required for the ‘certification to withstand ball impact’ of the materials in accordance with ‘Prüfung der Ballwurfsicherheit, DIN 18032 Teil 3, Sportshallen für Turnen und Spiele’ (requirements and testing of ball impact safety, DIN 18032, Part 3, sports facilities). The tests are carried out at a laboratory in the facility for research and materials testing for the construction industry (Forschungs- und Materialprüfungsanstalt für das Bauwesen (FMPA)) at the Otto-Graf Institute at the University of Stuttgart. The CE standard for suspended ceilings, EN 13964, also includes ball impact certification as a parameter, and the German tests are performed accordingly. In accordance with EN 13964, Annex D, Impact resistance, Troldtekt is classified as class 1A.

A wide range of structures fitted with Troldtekt acoustic panels have been tested at the institute in Stuttgart and have been approved for use as ceiling and wall cladding in sports facilities. This applies to structures on wooden battens as well as structures suspended in C60 profile systems.

Prüfung der Ballwurfsicherheit DIN 18032, Teil 3, Sportshallen für Turnen und Spiele / EN 13964, Annex D, Impact resistance.

Ceiling cladding

A handball is thrown 36 times against the test ceiling at a velocity of 16.5 ± 0.8 m/s. The shots are thrown 2 × 12 times at an angle of 60° and 1 × 12 times at an angle of 90°.

Wall cladding

A handball is thrown 54 times against the test wall at a velocity of 22.5 ± 1.2 m/s. The shots are thrown 2 × 12 times at an angle of 45° and 1 × 30 times at an angle of 90°.

Safety is paramount in indoor shooting ranges

Troldtekt meets the high requirements for indoor shooting ranges in accordance with the German Shooting Range Regulation (Schießstandrichtlinie, SRL) with regard to:

  • the ricochet and rebound behaviour – a projectile energy of up to 7,000 joules
  • preventive fire protection
  • noise protection

35 mm Troldtekt acoustic panels of the ‘Extreme Fine Structure’ type with an intermediate mineral wool/stone wool layer of 40 mm – 50 kg/m3 were tested. Pages 1+26 of the shelling report (VPAM test regulation ARG 2012 version 2 of 14/05/2014) download here or request in full from the relevant Troldtekt project consultant or area manager.

Troldtekt acoustic panels are made of the natural materials of wood and cement and are CE marked in accordance with DIN EN 13168. Troldtekt is classified as a flame-retardant building material (B-s1, d0) and is tested and classified as non-flammable (A2-s1,d0) (download certificates). Troldtekt acoustic panels achieve high sound absorption values over the entire frequency range. (Download sound absorption values).

Natural strength
Natural strength

When planning indoor shooting ranges, special requirements pursuant to the Shooting Range Regulations of the Federal Ministry of the Interior (BMI) (of 23 July 2013, first amendment of 13 March 2013) must be observed in regard to the sound absorption and fire protection. In addition, precautions must be taken against ricocheting and rebounding projectiles or projectile parts when designing indoor shooting ranges.

Sound absorption

Behind the firing line, the walls and ceiling of the shooting range must be covered with sound-absorbing material, depending on the precise use, as residents and other persons must not be affected by the shooting noise (up to 160 dB).

Indoor shooting ranges are facilities in accordance with section 3(5) of the German Federal Immission Control Act (BImSchG) and are subject to the requirements of section 22 of that act. The permissible immission reference values of the Technical Instructions for Protection against Noise (TA Lärm) must be observed.

For the selection of sound-absorbing materials within the shooting range: the mean reverberation time should not exceed the required value of T60 < 0.5 s over the frequency range from 125 to 4000 Hz. The mean sound absorption level should not be less than the required value of αs > 0.5 at the octave average/mean frequency of f = 500 Hz, which is relevant for shooting noise.

Fire protection

It must be ensured that the wall and ceiling materials used do not drip or develop toxic gases in the event of a fire. The sound-absorbing wall and ceiling coverings used in indoor shooting ranges must be at least flame retardant according to building material class B 1 in accordance with DIN 4102, Part 1. According to DIN EN 13501-1, at a minimum the criteria C, s1 and d0 must be met.

Ricochet protection for ceilings and walls

The cladding must be smooth and ricochet-proof. The following safety requirements for the materials to be used must be ensured:

Impacting projectiles must be safely absorbed at a hit angle between 25 degrees and 60 degrees. Projectiles or parts thereof may not ricochet back from the surface towards the shooting positions; the visible material surface must be flat and resistant to abrasion and mechanical stress. Test confirmations or certificates for the resistance of the material used against ricochet and rebound must be available.

Shooting range Gersfeld

After an extensive renovation, the shooting ranges in the German town of Gersfeld have been brought up to date with the latest technology.

Of immense importance are the rebound-proof panels which cover the floors, walls and ceilings of the shooting range. Among other things, Troldtekt acoustic panels were used for this purpose.

The acoustic panels not only optimally insulate the sound and retain the heat in the premises, but they also reflect the light evenly and slow down projectiles to keep them from becoming a danger to the markspeople. 

>> Read more and see more photos

Natural strength