A method for coating a solid surface with a recombinant spider silk protein capable of forming polymeric, solid structures, comprising the following steps: - exposing the solid surface to an aqueous solution of the recombinant spider silk protein and thereby forming a surface layer of the recombinant spider silk protein adsorbed on the solid surface without formation of covalent bonds between the recombinant spider silk protein and the solid surface; and - further exposing the surface layer of the solid surface to an aqueous solution of the recombinant spider silk protein and thereby forming an assembled silk structure layer of the recombinant spider silk protein on the surface layer; wherein the method does not include drying-in of spider silk protein; wherein the recombinant spider silk protein is comprising the protein moieties REP and CT, wherein REP is a repetitive fragment of from 70 to 300 amino acid residues, selected from the group consisting of L n L, L n AL, L n L, and L n GL, wherein n is an integer from 2 to 10; each individual A segment is an amino acid sequence of from 8 to 18 amino acid residues, wherein from 0 to 3 of the amino acid residues are not Ala, and the remaining amino acid residues are Ala; each individual G segment is an amino acid sequence of from 12 to 30 amino acid residues, wherein at least 40% of the amino acid residues are Gly; and each individual L segment is a linker amino acid sequence of from 0 to 30 amino acid residues; and CT is a fragment of from 70 to 120 amino acid residues, having at least 70% identity to SEQ ID NO: 3 or SEQ ID NO: 69; and optionally a functionally exposed non-spidroin protein/polypeptide moiety. - exposing the solid surface to an aqueous solution of the recombinant spider silk protein and thereby forming a surface layer of the recombinant spider silk protein adsorbed on the solid surface without formation of covalent bonds between the recombinant spider silk protein and the solid surface; and - further exposing the surface layer of the solid surface to an aqueous solution of the recombinant spider silk protein and thereby forming an assembled silk structure layer of the recombinant spider silk protein on the surface layer; wherein the method does not include drying-in of spider silk protein; wherein the recombinant spider silk protein is comprising the protein moieties REP and CT, wherein REP is a repetitive fragment of from 70 to 300 amino acid residues, selected from the group consisting of L n L, L n AL, L n L, and L n GL, wherein n is an integer from 2 to 10; each individual A segment is an amino acid sequence of from 8 to 18 amino acid residues, wherein from 0 to 3 of the amino acid residues are not Ala, and the remaining amino acid residues are Ala; each individual G segment is an amino acid sequence of from 12 to 30 amino acid residues, wherein at least 40% of the amino acid residues are Gly; and each individual L segment is a linker amino acid sequence of from 0 to 30 amino acid residues; and CT is a fragment of from 70 to 120 amino acid residues, having at least 70% identity to SEQ ID NO: 3 or SEQ ID NO: 69; REP is a repetitive fragment of from 70 to 300 amino acid residues, selected from the group consisting of L n L, L n AL, L n L, and L n GL, wherein n is an integer from 2 to 10; each individual A segment is an amino acid sequence of from 8 to 18 amino acid residues, wherein from 0 to 3 of the amino acid residues are not Ala, and the remaining amino acid residues are Ala; each individual G segment is an amino acid sequence of from 12 to 30 amino acid residues, wherein at least 40% of the amino acid residues are Gly; and each individual L segment is a linker amino acid sequence of from 0 to 30 amino acid residues; and n is an integer from 2 to 10; each individual A segment is an amino acid sequence of from 8 to 18 amino acid residues, wherein from 0 to 3 of the amino acid residues are not Ala, and the remaining amino acid residues are Ala; each individual G segment is an amino acid sequence of from 12 to 30 amino acid residues, wherein at least 40% of the amino acid residues are Gly; and each individual L segment is a linker amino acid sequence of from 0 to 30 amino acid residues; and CT is a fragment of from 70 to 120 amino acid residues, having at least 70% identity to SEQ ID NO: 3 or SEQ ID NO: 69; and optionally a functionally exposed non-spidroin protein/polypeptide moiety.