11 this sheet may be the sole sheet between ticking 13 and watermattress 11 as seen in fig4 and if the sole sheet may be about 1 8 34 thick however if desired as seen in fig3 a plastic sheet 19 39 such as a sheet of open celled polyurethane foam may be provided between sheet 20 and ticking 13 a similar sheet 21 of plastic again such as open celled polyurethane foam may be provided between ticking 13 and sheet 19 39 finally a sheet 22 of a plastic material such as closed cell polyurethane foam may be provided between sheets 21 and 19 39 if the arrangement of sheets 19 39 and 20 to 22 as seen in fig3 is used sheets 20 and 22 may be about 1 32 to 1 8 inches in thickness and sheets 19 and 21 may be about 1 2 to 11 2 inches in thickness these sheets 19 39 and 20 to 21 may be merely disposed below ticking 13 or sewed thereto as by quilting preferably however an adhesive is provided between ticking 13 and sheet 21 between sheets 21 and 22 between sheets 22 and 19 39 and between sheets 19 39 and 20 in the embodiment shown in fig4 an adhesive or sewing as by quilting may be provided between ticking 13 and sheet 20 state of the art adhesive may be used the arrangements of layers 13 and 20 on watermattress 11 of fig4 and the arrangement of layers 13 and 19 39 through 20 in fig3 form a laminate which eliminates mildewing and the formation of water condensation.