I've recently purchased a home that has a 10 year old deck. The deck appears to be structurally sound but has some age and wear. I also want to waterproof the bottom of the deck to keep the patio below dry. Please note that I have no experience with decking so I might not be using appropriate terminology for things.

Should I look at staining the deck, sealing it or maybe painting it? Ideally I would like to have the boards not so rough and have a cleaner appearance.

Any recommendations on systems or sheeting to attach under the deck to waterproof the below patio?

Lastly, please look at the pictures below of my deck and advise if there are any structural changes that I should consider making.

Boards cracked and weathered:


Railing bowed out:


Notice there is a single cross board under the deck, what purpose does it serve?


Beams (slightly cracked):



Stairs:


Underside of deck:








Thank you and regards!

 

It looks like you have a solid stain on the deck. You could clean it and apply another coat of solid stain if you want to freshen it up or change the color. The cracks in the wood are normal. There isn't a whole lot you can do about the decking although a little sanding and/or setting any nails that stick up might help some.

I've never seen a board installed like that on the bottom side. Maybe the joists where bowing out some and they used that board to straighten them out

There are systems designed for shedding water under a deck but I don't know a lot about them ... but we do have some members that do so stayed tuned