I used spruce wood. I left a gap in the carpet to aid in draining. I'd say these boards will last for years. I can't really add anything that BTO and Ship haven't already said. I know that these new boards are giving some added support because my boat has "settled in" because the new boards now have formed fitted to the hull. My new boards have on been on 10 days. Like I said in earlier post I'm very pleased. The weather has kept me off the water, but I'm positive it's really gonna be a huge help on all the ramps I use. I'm am so happy I did this modification....worth every penny I paid....and then some.