Method of field joint coating, comprising the steps of: - providing two lengths of pipe (7, 9) coated with a thermoplastic polymeric material coating, preferably a thermo-insulating coating, wherein at least one end (7a, 9a) of each length of pipe is uncoated along a certain part of the length of pipe; - placing the ends (7a, 9a) against each other; - applying a girth weld to join the ends to form a pipeline coated with the coating and with a gap in the coating surrounding the girth weld; and - filling the gap in the coating with a coating, preferably a thermo-insulating coating, by placing in the gap a mixture of solid elements and a thermoplastic polymeric material in fluid state; and letting the thermoplastic polymeric material in fluid state solidify, wherein the method step of placing the mixture in the gap comprises: - providing the solid elements, which comprise polymeric material, and introducing the solid elements into the gap by - forming a stack of the solid elements or pre-bonding the solid elements into a pre-form (51, 53) while leaving interconnected spaces between the solid elements; and - forcing the thermoplastic material in fluid state through and into the interconnected spaces between the solid elements, thereby filling the volume of the interconnected spaces between the solid elements with the thermoplastic material in fluid state. - providing two lengths of pipe (7, 9) coated with a thermoplastic polymeric material coating, preferably a thermo-insulating coating, wherein at least one end (7a, 9a) of each length of pipe is uncoated along a certain part of the length of pipe; - placing the ends (7a, 9a) against each other; - applying a girth weld to join the ends to form a pipeline coated with the coating and with a gap in the coating surrounding the girth weld; and - filling the gap in the coating with a coating, preferably a thermo-insulating coating, by placing in the gap a mixture of solid elements and a thermoplastic polymeric material in fluid state; and letting the thermoplastic polymeric material in fluid state solidify, wherein the method step of placing the mixture in the gap comprises: - providing the solid elements, which comprise polymeric material, and introducing the solid elements into the gap by - forming a stack of the solid elements or pre-bonding the solid elements into a pre-form (51, 53) while leaving interconnected spaces between the solid elements; and - forcing the thermoplastic material in fluid state through and into the interconnected spaces between the solid elements, thereby filling the volume of the interconnected spaces between the solid elements with the thermoplastic material in fluid state. - providing the solid elements, which comprise polymeric material, and introducing the solid elements into the gap by - forming a stack of the solid elements or pre-bonding the solid elements into a pre-form (51, 53) while leaving interconnected spaces between the solid elements; and - forcing the thermoplastic material in fluid state through and into the interconnected spaces between the solid elements, thereby filling the volume of the interconnected spaces between the solid elements with the thermoplastic material in fluid state.