A method for mounting a prefabricated construction element comprising concrete to another construction element, wherein the method comprises a connecting step for connecting the prefabricated construction element by means of repeatably openable and closable mechanical connection means to said another construction element so that a joint is formed between the prefabricated construction element and said another construction element, a grouting step for grouting the joint by covering the joint at least partly with grout and allowing the grout to harden, and a coating step for coating surfaces of the prefabricated construction element that is to be covered by grout in said grouting step at least partly with separation means prior said grouting step, wherein the connecting step includes providing repeatably openable and closable mechanical connection means comprising anchor bolts extending from said another construction element, wherein the connection step includes screwing first nuts on the anchor bolts so that the nuts are at a distance from said another construction element, wherein the connection step includes arranging the anchor bolts to penetrate openings in the prefabricated construction element so that the first nuts are between said another construction element and the prefabricated construction element and a grouting space is formed between said another construction element and the prefabricated construction element, wherein the connection step includes screwing second nuts to the anchor bolts to secure the prefabricated construction element to the anchor bolts. wherein the connection step includes arranging the anchor bolts to penetrate openings in the prefabricated construction element so that the anchor bolts extend into a cavity in the prefabricated construction element, wherein the connection step includes screwing said second nuts to the anchor bolts inside the cavities so that the second nuts will be housed in the cavities, characterized by a filling step for filling the cavities at least partly with other material than grout prior said grouting step to at least partly prevent grout from entering said cavities, and by using at least one of mineral wool, gypsum, plaster and lime mortar as said other material in the filling step. a connecting step for connecting the prefabricated construction element by means of repeatably openable and closable mechanical connection means to said another construction element so that a joint is formed between the prefabricated construction element and said another construction element, a grouting step for grouting the joint by covering the joint at least partly with grout and allowing the grout to harden, and a coating step for coating surfaces of the prefabricated construction element that is to be covered by grout in said grouting step at least partly with separation means prior said grouting step, wherein the connecting step includes providing repeatably openable and closable mechanical connection means comprising anchor bolts extending from said another construction element, wherein the connection step includes screwing first nuts on the anchor bolts so that the nuts are at a distance from said another construction element, wherein the connection step includes arranging the anchor bolts to penetrate openings in the prefabricated construction element so that the first nuts are between said another construction element and the prefabricated construction element and a grouting space is formed between said another construction element and the prefabricated construction element, wherein the connection step includes screwing second nuts to the anchor bolts to secure the prefabricated construction element to the anchor bolts. wherein the connection step includes arranging the anchor bolts to penetrate openings in the prefabricated construction element so that the anchor bolts extend into a cavity in the prefabricated construction element, wherein the connection step includes screwing said second nuts to the anchor bolts inside the cavities so that the second nuts will be housed in the cavities, characterized by a filling step for filling the cavities at least partly with other material than grout prior said grouting step to at least partly prevent grout from entering said cavities, and by using at least one of mineral wool, gypsum, plaster and lime mortar as said other material in the filling step.