Marine Panels
Rockwool Marine & Offshore is a world leading supplier of core material for a large range of marine panel producers.
The marine approved sandwich panel is a well know building method for accommodations, where the requirements are often a combination of the need for B-15 / B-30 fire protection and a request for noise reduction between the individual cabins, salons, public areas, etc. The Rockwool range of Marine Slab products offers an excellent choice in material, as it provides both a high fi re resistance, mechanical strenght and superb noise reduction ratio to the weight.
The design of marine panel system provides a high range of different solutions. Similar to heat transfer in fire, great care has to be taken concerning joints and edges, as poor design here can lead to passage of sound.
As seen in the test result Rockwool has performed a reduction measuring on a principle built-up of an A-30 fire protection combined with a standard 25 mm panel. The result is a Rw value of 62 dB.

Standard 25 mm single panel. Typically 0.8 mm steel sheets on each side with, as example, 160 kg/ m3 Rockwool lamellas as core material.
Rw will typically be in the area of 30 - 38 dB. These are in the low range of noise reduction, but still impressively high result for such a thin construction.

Noise Panel by i.e. 50 mm. A noise specified panel, where a simple single panel solution is required. A much higher reduction can be obtained if the panel is made with an air gab in the middle.
This requires more specialised built-up but with a single 50 mm panel it is achievable to gain a reduction around Rw 42 - 50 dB. Studies have shown that an approx. 3 mm gab is best for a general average damping. If damping in specified frequency ranges is required other size of air gabs is needed.

Where the need is for highest reduction, it will be required to make a double panel system. Here it is also possible to create to some extent a specifi ed frequency damping, depending on the distance between the two panels.
It will also be an advantage to fill the void between the two panels by some Rockwool in lighter densities, i.e Marine Batts 45, to avoid standing waves. Depending on panel type, inter distance and infi ll it is possible to obtain reduction values of as high as; Rw 48 - 70 dB.