The calcium silicate boards should lie flat during installation. If your substrate (wall or ceiling) has unevenness or holes, we recommend that you first level it so that the calcium silicate boards can lie flat during subsequent installation. Smaller unevennesses can be evened out with the silicate adhesive, for larger unevennesses or holes we recommend lime cement plaster.
We recommend that you pre-treat the substrate with the silicate primer before installing the calcium silicate boards.
