Our 5/8" Premium Soft Wood Tiles are made with foam and are not the most impervious to the elements, but they can be used outdoors on a deck or as a boat floor. On a boat, since these tiles have a laminate top, the flooring may become a slick when wet. We would recommend making sure that any water that gets on the flooring is cleaned up quickly. Since these tiles weren't meant to handle the elements, they may not last very long in an outdoor setting. Since these foam tiles are installed as a floating floor, they are very easy to install and replace, so we would suggest ordering more than is needed for a little back stock for replacements.