To prolong the life of your new deck, we recommend using G-Tape. It is a flashing tape that will keep moisture from damaging your new joists and bearers. We will supply and install this product for the price listed. This is a price per m² so if your deck is 6m x 4m (24m² in total), you would enter 24 into the quantity. If your deck is 3m x 6m (18m² in total) you would enter 18 in the quantity.