We want to insulate our garage and the attics above by the interior; a craftsman proposes us for the walls of Styrodur. What worries me is the fact that it burns easily by releasing toxic fumes (?) Especially with the electrical panel in the middle. What do you think? If not, is it a good insulation or is it better to stay on rockwool?
Styrodur is a very interesting product for outdoor insulation because it is not very reactive to water, it is a good insulation that has been proven. However, it is true that it is classified E by the system of European harmonization of Euroclasses reaction to fire; that is to say, it is considered as a combustible product whose standard considers that "the contribution to the general conflagration is very important".
Mineral wools are noncombustible and respond to your concern. You can also use composite panels (insulation + plasterboard) for a good surface finish. Consult our sheet on the installation of composite panels.
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