Abstract: A floating drain seal organization is utilized in combination with a drain formed with a conical bottom surface and a coaxially aligned outlet pipe. A float plug with a complementary conical bottom surface is spaced from the bottom surface of the drain to effect passage of drainage water therebetween. The float includes a planar top surface cooperative with an annular tubular seal coaxially spaced exteriorly of a circular matrix of openings. The float includes a hemispherical depression formed coaxially into its top surface to receive a hemispherical bottom portion of a seal coaxially aligned within the drain to effect sealing of the drain when a plugged or a slowed drain condition backs up drainage water therethrough.