ᐅ Electrician's chases – how to fill them?

Hello everyone,

We are building a KFW 55 house. Now a question has come up for us: Should the shafts installed by the electrician for the cables be filled with a special mortar (insulating or similar), or is it sufficient to use regular mortar?

Best regards,
Ramona_91

Are they unused?

Sorry, no, there are pipes in there. However, before applying the interior plaster, some filling should still be done.

Do you mean dedicated shafts, or the usual channels in the walls?

I mean the standard slots.

Under no circumstances use mortar... it will just cause everything to deform later... simply use bonding plaster, for example Rotband.