Need input on a large free standing deck design and roof

by Russ
(Cedar Creek, TX)

Hi folks, totally did not know about this site but just found it.. heh.

Please forgive me if I confuse you all and ramble or if I type more than I should. I love designing decks almost as much as sitting on them and I generally run out of folks to talk to in the design phase for this deck.

I, like all of you I am sure, have a hard time finding people that I can discuss design ideas with as they either glaze over or have no clue. Each house we have been in, I have designed a different deck. The latest house, the LAST house.. lol.. I am having a hard time with as it is soooo unique.

So, need some input.

I build things really strong, or try to. This one poses an issue as there is a lot of wind out here as well as there is a detached garage that it would span between and a walkway, which I am thinking to handle separately. Suggestions are very welcome.

Here is my idea for the main deck (pictures to be uploaded..but I am not an artist.. heh)

61 ft wide, rules of three for depth. The garage sets the depth.

I will not be (or am not expecting to) connect this deck to the house. I expect to "butt it up" as close as I can, and there will be gutters running the water under and out.

The initial plan was to plant stripped cedar trunks/posts (11 of them) on the perimeter of the deck and sides. These would be at a depth of at least 36" and in concrete with gravel under them for drainage.

They would be 14ft tall, and at least 8" at the top, so 10-12" at the base.

I WAS going to place standard treated 6x6 posts on TOP of the deck along the house border, but I have recently wondered if using 8 of the same stripped cedar posts might be more stable, since I would dig them 3ft in the ground as well.

My idea was to place a dual 2x8 beam around the bottom as well as the top of the cedar posts and notch the posts about 1-2" then bolt the beams into the notches.

I would also place, below the deck, 6" cedar posts to support the undercarriage. There would be no joists spanning more than 7.5ft and all joists would be treated 2x8 boards, single, on 16" centers. There would also be one more dual 2x8 beam across the center and a shorter one in the back supporting the area in the center, so the joists would also not span more than 7.5'.

Now, the real meat of the conversation... will the roof be supported enough?

In the drawing I uploaded, the entire perimeter is supported by those cedar posts and that has a dual 2x8 beam bolted to it.

I plan to use 2x8's for the rafters and space them no greater that 12" on center. I know that is a lot, but I want to keep it uniform and the center is about 18.5 ft deep.

I will add a radiant barrier and then 26ga metal roofing to it with gutters and drip edges.

I also expect to add a few ceiling fans and lights, nothing too major.

This is Texas, so we do not get snow, really.. heh.. and I am looking at a gentle slope, whatever I can get out of it.. thinking 12/3-ish, maybe 12/2. (outside the city so no inspections/code, but I want it to be safe)

For the walkway, I plan to design it's own little roof, and have it overlap the house and garage and deck roof for drainage. I will actually design attachments to secure that to each roof for wind protection.

So... too much?

Again, sorry.. I am just wondering if the roof will have enough support.

Picture 1 - The blue dots are possible cedar posts

The dark green dots are also cedar posts.

The bright green are 6" cedar posts supporting the base.

Picture 2:

This is the design we had before I thought about the roof. In this, I was planning to just add 6x6 posts on top of the deck with brackets to support the roof.

I was thinking this may not be as strong, since I am not attaching the roof to the house.

Picture 3 - Back of the garage and walkway

Picture 4 - Back of the kitchen and bedroom

Ideas?