Detail waterproofing a chimney or vent with mariseal system 250. the procedure would: - apply primer or mariseal mariseal 710 aqua coat - apply mariseal 250 in the fireplace and around it. - placement of the first reinforcement mariseal fabric circular shape in corners impregnated mariseal 250 - placement of the second reinforcement mariseal fabric on the entire surface of the conduit a short overlap. - placement of the third reinforcing fabric mariseal at the base of the chimney. - application of mariseal system 250