Insulating element for externally attachment to an external wall, consisting in a single block, normally rectangular, of insulating material, the insulating material being expanded polystyrene, EPS, or extruded polystyrene, XPS, the block having a back side, a front side, a top, a bottom, a first and a second side, wherein the back side in use will be facing a wall it will be mounted to, and the front side which in use will be facing away from the wall it is to be assembled to, and a first set of a plurality of drainage channels in a first orientation through the insulation material, wherein the first set of drainage channels are arranged in a vertical orientation from top to bottom of the insulation element, wherein the first set of drainage channels comprise a plurality of vertical drainage channels in two or more vertical layers relative the back side in the insulation element, wherein a second set of a plurality of drainage channels is arranged in a second orientation through the insulation element, wherein the second set of drainage channels are arranged in a horizontal orientation from the back side toward the front side of the insulating element, or the second set of drainage channels are arranged in an angular orientation, different from 90 relative the orientation of the first set of drainage channels from above on the back side downward toward the front side of the insulating element, wherein each drainage channel in the second set of drainage channels opens out, in one of: space created by projecting dimples/lugs arranged on the front and/or back side (6, 7) for channeling diffusion moisture towards the drainage channels, and into a first recess on the back side, and a second recess on the front side. the block having a back side, a front side, a top, a bottom, a first and a second side, wherein the back side in use will be facing a wall it will be mounted to, and the front side which in use will be facing away from the wall it is to be assembled to, and a first set of a plurality of drainage channels in a first orientation through the insulation material, wherein the first set of drainage channels are arranged in a vertical orientation from top to bottom of the insulation element, wherein the first set of drainage channels comprise a plurality of vertical drainage channels in two or more vertical layers relative the back side in the insulation element, wherein a second set of a plurality of drainage channels is arranged in a second orientation through the insulation element, wherein the second set of drainage channels are arranged in a horizontal orientation from the back side toward the front side of the insulating element, or the second set of drainage channels are arranged in an angular orientation, different from 90 relative the orientation of the first set of drainage channels from above on the back side downward toward the front side of the insulating element, wherein each drainage channel in the second set of drainage channels opens out, in one of: space created by projecting dimples/lugs arranged on the front and/or back side (6, 7) for channeling diffusion moisture towards the drainage channels, and into a first recess on the back side, and a second recess on the front side. space created by projecting dimples/lugs arranged on the front and/or back side (6, 7) for channeling diffusion moisture towards the drainage channels, and into a first recess on the back side, and a second recess on the front side.