Insulation

A method of providing a fire resistant layer to a support surface of a building element comprising:

• introducing a combination of first mineral wool fibres having a first composition and second mineral fibres having a second composition into an inlet of a spraying apparatus, the first mineral wool fibres and the second mineral wool fibres having a difference of softening point which is at least 150° C.;
• and
• projecting simultaneously the first mineral wool fibres, the second mineral wool fibres, water and a binder from a spraying nozzle of the spraying apparatus towards the support surface to provide a sprayed layer of mixed mineral wool fibres on the support surface, the sprayed layer of mixed mineral wool fibres comprising (in % by weight based on the total weight of the layer):
• the binder;
• at least 50% wt of the first mineral wool fibres;
• and
• at least 5% wt of the second mineral wool fibres.

A method of providing a fire resistant layer to a support surface of a building element, the method comprising:

• providing a package comprising a combination of loose glass wool fibres and loose stone wool fibres;
• introducing the content of the package into an inlet of a spraying apparatus;
• applying a primer bonding layer on the support surface;
• and
• subsequently projecting simultaneously the combination of loose glass wool fibres and loose stone wool fibres, water and a binder from a spraying nozzle of the spraying apparatus towards the support surface to provide a sprayed layer of mixed mineral wool fibres on the support surface, the sprayed layer of mixed mineral wool fibres comprising (in % by weight based on the total weight of the layer):
• the binder;
• at least 50% wt of the glass wool fibres;
• and
• at least 5% wt of the stone wool fibres.

A sprayed mineral wool insulating product provided on a support surface of a building element, the layer comprising (in % by weight with respect of the total weight of the layer):

• a binder;
• at least 50% wt of first mineral wool fibres having a first composition;
• at least 5% wt of second mineral wool fibres having a second composition;
• in which the first mineral wool fibres and the second mineral wool fibres have a difference of softening point which is at least 150° C., preferably at least 250° C.