waterproofing the seams on a 2X6 deck

[Bullwinkle]

I have a six by sixteen foot overhang that is standard 2X6” decking on 8 foot tall posts.

I want to close up and water proof the seams between the boards of the overhang to provide a dry area underneath. I have ordered some oakum (sp?) for a test, anyone willing to venture another solution?

[DanielP]

Bullwinkle,

I don't think that you will find anything that will do what you want. Sorry.

Can you suspend a corrugated roofing "ceiling" below the deck?

Otherwise I think that you will need a system that encorporates a membrane, whether under tile or a wear surface or a roofing membrane (this option not to be walked on).

The oakum needs to stay wet in order to seal. When it dries it will shrink back until it becomes saturated again, leaking in the mean time.

Sealing the seams in the deck is really impractical, as the deck boards will move constantly from heat expansion, wetting and drying, etc. etc.

Good luck, Dan

[dmbwest]

This will work for years to come.

http://solutions.3m.com/wps/portal/3M/en...8HT14PGTgl

aloha,
pog

[lquade]

yes the 3m product is good but depending on how wide the seams... wow isnt it 18 bucks a tube now? there would be the option of covering with marine plywood and then remember the forever floor that was on this forum? wonder how that would work, they used it in bathrooms etc?

[Bullwinkle]

I was thinking polysulfide or hot tar to finnish the seams. I have used tons of the 5200 - I get more on myself than the work - grin

[JWFITZ]

You might consider wedge seaming. I expect your deck has 3/8s or 1/2 inch placing. Cut stringers to span the caps a about a 3 degree gape, and drive them in. Gorilla glue is a good idea to chase them with. Be advised that the outside plank on the deck(deck clamp) will need to be very securely fastened, as as you drive the wedges in you'll elsewise blow it off the rail. It needs 6 inch lag bolts to something. Belt sand the whole deck fair. It won't leak, or any more than a ship's deck does. Oakum is of no use if you're filling anything that you can't drive against.

Don't rely on glues or goops. Very expensive and won't hold. You might consider cheap redwood for the wedges, as it's usually dry and soft. Run it through the tablesaw and mash it in with a block and a 5 pound mallet.

[JWFITZ]

You might consider wedge seaming. I expect your deck has 3/8s or 1/2 inch placing. Cut stringers to span the caps a about a 3 degree gape, and drive them in. Gorilla glue is a good idea to chase them with. Be advised that the outside plank on the deck(deck clamp) will need to be very securely fastened, as as you drive the wedges in you'll elsewise blow it off the rail. It needs 6 inch lag bolts to something. Belt sand the whole deck fair. It won't leak, or any more than a ship's deck does. Oakum is of no use if you're filling anything that you can't drive against.

Don't rely on glues or goops. Very expensive and won't hold. You might consider cheap redwood for the wedges, as it's usually dry and soft. Run it through the tablesaw and mash it in with a block and a 5 pound mallet.

[sittall]

I had a 7' x 16' lanai built with 2x6s. I wanted it dry underneath. Using roofing screws I attached light weight pvc roofing panels under the decking. Being short and 'older' I could only handle the 4x8 panels but 4x16 are better - if you have a way to get them home from HD.

Make sure to give them a slight slant so water will drain off. I put gutters on the edges and hung a chain to channel the water.

This is a good temporary solution that can always be removed. Later I replaced the 2x6 decking with plywood and used a special two layer coating to seal it.

[Bullwinkle]

Thanks for all for the input.... Still haven't decided... But I love the ideas - Thanks