Adding a deck with dry storage

[Perfectstranger]

I would like to add a deck to the back of the building with dry storage underneath. I would like to do it in stages, as the long term plan calls for storing recreational vehicles ( boat and pop up camper. I can get tji 22 foot long but how do I attach them? We would also like to build a cover for over for the first 11 feet. Then in the future add on again. Any input would be greatly appreciated

 

[Perfectstranger]

I have seen systems that catch the water between the joists and divert it but have not seen them used with tji just solid wood. Some sort of membrane? We only get about 20 inches of snow a year, if that helps.

 

[Kaizen]

can you describe the dry storage? like boxes and stuff?
I put some shims under my deck so its pitched and screwed roof metal to it upside down. problem isn't so much the snow as those times when it freezes to ice. I've had some rip off. very hard to be totally dry imo unless you build the deck like a flat roof. doesn't sound like you need anything more then dimentional lumber but I would figure out the whole plan so you build the stages to support the future.
for dry i'd consider a plastic shed under there.

 

[southalabama]

I've pondered the same question for storing small items such as fishing gear, life jackets, etc. After much thought I decided to go with dry deck storage boxes.

I think you should just add to the roof and extend the building. Trying to build dry storage under the deck your gonna have to basically build a roof under the deck. Why not go ahead and build the roof? Just my thinking but then again we measure rain in feet along the gulf coast.

 

[Perfectstranger]

I didn't explain very well. In the picture I am standing to the east of the building looking north. I can get enough 22 foot tji that I would like to use as the floor joists. I would enclose the east and south sides and put a 16x9 garage door facing west. This area would be parking for a boat and future camper. We would like a cover over the first 10 or 11 feet leaving the southern half uncovered. I would like to use the tji as I can get them for around 500. The question I guess is anybody have any experience with a membrane roof? How are they to walk on? This upper deck area would not only be a recreational area, but an extension of the hobby area which is on the other side of the patio doors. The patio doors open to 6 feet. Hope this helps

 

[matt_i]

You have to keep in mind the basic premise that a TJ I-joist is an interior framing member...iow not treated wood designed to be outside as in a traditional deck.

So this rules out using the under-floor water-catcher system.

I think you are going to have to do an EPDM sheet roof or a metal roof. Then figure out how to "float" the decking over top of that. The sticky part is going to be the handrail posts as those pretty much have to be penetrations thru the membrane, sealed and flashed with high attention to detail, and high stakes as with EPDM its a single piece of expensive material with no (probably limited...) second chances. I think there are some articles in Fine Homebuilding within the last few years which have some more info and build-case-studies.

 

[dave89iroc]

membrane roof with a slope and curbs, one or 2 openings at the low side of the slope, railings fastened to the top/outside of the curb, floating deck leveled on top of the membrane


https://www.google.com/webhp?source...&espv=2&ie=UTF-8#q=wood deck on membrane roof

https://ds3vvyqfhyred.cloudfront.net/1/pdf/magazine-articles/decking-over-a-roof.pdf

 

[kwb]

Look into Gaco Deck or Duckback - basically elastomeric paints to create the surface.

Materials for this aren't that expensive and doing this in phases seems like it would be a PITA, just save up a bit longer and be done with it.

The other option would be to do a concrete deck over conventional framing using corrugated metal roofing as the pan to pour onto.

 

[Perfectstranger]

Phase one using tji add 22 to the back of the building. I would like it to have a flat roof with a deck to utilize the patio door on second floor. This deck would have a cover extending from the back of the building 10-12 feet. This would be enclosed with a 8x16 door.
Phase 2 is adding another 10-20 feet on the end of that. This would house the yard equipment.
I know this isn't preferred but, there is a budget to contend with. Also the HOA only allows one outbuilding.
The long term plan is to end up with the attached garage for parking of daily drivers. Downstairs of the shop for wrenching, upstairs for wood working. First addition to store boat and camper. 2nd addition to store yard equipment, small tractor.

 

[volleyball]

This is easy to do. Just frame it for a floor that will support the live and dead load for your area. You need to frame it for a porch, not a deck. Meaning the joists go parallel to the building. You need to incorporate a pitch of a couple of inches down away from the building. Cover it with aluminum interlocking decking. The decking will keep it dry. And give you a deck to walk on. There are now I joists that are pressure treated.
I built a deck using LVL's and PT 18 x 28 years ago and it has remained dry underneath. I do have walls and a floor underneath.

 

[davewo]

I rebuilt my 12' X 55' deck as a flat roof (1/8" slope per 1') and glued down epdm pond liner to the OSB with outdoor carpet glue two years ago. This summer I got around to covering it with high end outdoor carpet, again using the outdoor carpet glue. You can weld seams in epdm no problem. I would recommend actual roofing epdm since the pond liner comes with chalk all over it.

 

[theoldwizard1]

Flat roofs really should NOT be flat ! They need a small amount of pitch AWAY from the existing structure toward a scupper/drain. Proper installation and quality products are key.

If you want a walking surface, you should build a light weight, removable deck style floor above it.

 

[fastjohnny]

http://www.nexaninc.com/products/decking/lockdry-waterproof-decking

Was well worth the cost for me with deck over living space

 

[ItsNemo]

I've seen this used up here in Canada to waterproof under a deck. Seems to work okay.

http://www.trexrainescape.com/

 

[Toolfool]

Build the storage space as an added room (foundation,walls,etc....) and find someone who does fiberglass deck coating over 3/4" plywood. We use a guy who covers the entire deck in fiberglass, flashed to the main building and seals around the rail posts. Totally waterproof. We've done them over living space on million dollar homes 20+ years ago and still perfect. Maintenance is only a fresh coat of paint rolled on every couple of years.