Decks, Patios, Porches and Docks - Deck flooring material

We are replacing a "deck" (8 x 16) that was entirely under the roofline of our house (including a 2' set-back from the eaves). It was set into the corner of the upper story of two stories. The existing structure was of "interior grade" (no real weather resistance materials except a steel hand rail). Although the eaves are wide, it still rained onto it and after 40 years the outer portion rotted. We have removed everything except the corner post (6x6 x approx. 16') and some temporary bracing. The location is in Portland, Oregon.

We would like to install a solid surface to prevent water from dripping onto concrete patio below and also extend the deck out the long side an additional 2-4' which would make part of the surface exposed. Is there an attractive but inexpensive way to make a weather resistance but solid floor (the material would go across the entire floor)? I would like to build the floor structure out of regular lumber. The sides would be protected by lap cedar siding (same construction as the house exterior) but I need to have a good solid weather resistant surface on top. Is there some type of reliable coating you could put over plywood (some type of heavy paint) or some type of sheet vinyl floor? I'm reluctuant to use tile over a wood floor since any microcrack woudl be an instant leak. Is there an elastic caulking by chance?

I will be able to monitor any leaking from underneath as it will be exposed joists.

Thanks in advance,
Mark

get an epdm contractor to put a "roof" on.. then you can simply deck over it .. the epdm is typically run up the sides of any "walls" a bit to ensure leak free for 30 or so years.. never DIY but i guess you can buy epdm and all .. try the roofing forum..

hope this helps--Josh

If I understand it correctly, you have a deck above a concrete patio and you want to prevent any water from going thru your deck and onto your concrete patio below?

You could do like Josh suggested and put down a solid surface and then deck over that. The first thing that comes to mind would be to use exterior sheathing over your joist then go over it with Weather Watch Ice and Water. This is a flexible roofing material with a self stick adhesive back usually used up here in the North East to help prevent ice damming. I know it comes in rolls, and wanna say it's either 3'x50' or 4'x50 for around $55 a roll. I used it around my skylights and down the valleys in my roof.

One question I have is what's going to happen to the water now that it can't go thru the deck and onto the ground below? If you're looking to totally stop the water from going thru, then I would say the deck should have a slight pitch and a gutter attached to carry the water to a desired location. Standing water on wood with no place to go isn't a good idea.

Your assumptions are correct, with the exception that only a minor portion of the deck will be directly rained on. While I would definitely slope it away from the house the ground below is fairly porous and slopes away from the house.

I'm also of the opinion that, before I build a "roof" underneath the deck, I would just build a "deck". What water does go through won't be any harm. I was just hoping to find an inexpensive but effective solution to a "solid surface" deck. Sounds like it doesn't exist.

Thanks for everyone's input.

Mark

This is what I'm going to do. http://www.underdeck.com/
It is a little spendy but me managed to find it half off at home depot. We plan on putting in a screen patio below our deck.

How about a concrete topcoat (3-4" thick). This would be a good solid surface and prevent water from dripping through.