Need to replace deck boards. Some questions

So over the past year some of my deck boards have rotted through. As it’s starting to cool down now, and the price of lumber is going back down, I figured it’s a good time to start planning.

My deck is roughly 15x16, using 2"x6"x16’ deck boards.

I took a look underneath and the frame looks good. Will know for sure once I pull the boards up.


  • Can I stain/seal the boards before installation?
  • Is there a correct gap that should be between the boards?
  • What do I need to waterproof the area between the deck board and frame?
  • Should I seal the frame or do any maintenance to it?
  • Any other considerations?

Pics Incoming.


  1. Most sources recommend 30 days after install to seal because of preservatives in the wood but I’ve done it after 1-2 weeks.
  2. 1/8in
  3. Not sure what you’re referring to.
  4. You can re-seal and replace any questionable joists. Depending on sub structure, resealing may not be necessary.

Have you thought about composite? Lasts longer, looks better. is straighter and doesn’t need to be sealed.

You can definitely seal or stain them before putting them in. It’s also easy enough to use a roller and do it after. What we’ve used is a 16penny nail as a gap. but I think 3/16" would be good. You do not need to waterproof the framing anywhere or where the decking touches the framing. Just remember to put the flashing on the ledger board that attaches to the house. you might bust it up while removing the decking. It’s just window flashing
The framing is pressure treated and you don’t need to seal that. Composite is great. heavy as fuck and expensive! special screws so more expensive. Expands, so any pieces butted together at the ends exposes a gap when it shrinks. Hot to stand on barefoot. I would be aware of the gap you create between boards. Wood will swell and also get filled with pine needles or such. You’d like rain and shit to fall through.

Yeah I’ve looked into composite but its too expensive, I would also need to modify the frame.