So, after putting in over 200 screws to silence some poorly installed stairs I am getting ready to apply surfix to them this weekend (had 2 year old and 4 year old Grandsons last weekend, so, decided to delay [scared]) This being my first time doing it, I was planning on 3 coats and then the final buff. My question is should put any kind of sealer over the final product or is the surfix coating good enough for normal traffic?