Should I leave a gap when using any trimming product? A Should I leave a gap when using any trimming product? When using any of our featured trimming products, you should leave an inch (1″) after inserting mats into the trim. This will allow mats to “float” or expand and contract within the trim during seasonal temperature changes. Share facebook twitter linkedin pinterest email Back to Top What do I do if I have a drain? How about a pole? Can G‑Floor be molded up/installed on the wall a bit?