How to Maintain Fiberglass Decks

Clean the fiberglass deck every month or as needed, depending on how dirty it gets. The key is to clean off dirt as it accrues before it becomes caked on. To clean the deck, brush it thoroughly with a broom. Or, if the dirt is caked on and will not brush away, wet down the deck with a hose and use a scrub brush to break up dirt. Use general purpose household cleaners as needed on difficult stains such as juice spills, grease or food stains. Then rinse with the hose.

Replace damaged planks by prying them up from the decking with a crowbar. A damaged plank must be replaced when the dent or crack penetrates or exposes balsa wood core. Install a new plank in place of the old one and nail it into the deck joists with 3-inch decking nails.

Use a pressure washer on trouble areas. Set the device on medium by turning the power knob to the mid-setting, and adjust the nozzle to form a tight spray line. Rotate the end of the nozzle to try different types of sprays and see which works best. Move the pressure washer back and forth to remove mold or tough dirt stains. Then rinse the deck with a hose and clean water.