Moccasin, I gather from your MyPage and postings that the garage in question is in Mobile, AL, i.e. coastal hurricane zone? If so, 'cement block garage' probably means STEEL-REINFORCED concrete block, aka 'CBS' (concrete block stucco). Is the block exposed and visible on the interior of your garage? Do you see a poured concrete bond beam (aka 'tie beam') running the perimeter at the top of the walls, to which the roof is tied? If so, that beam is tied to the slab via several rebars and poured columns running down through the cavities in your block walls. VERY STURDY construction. Regardless, the extensive mods you've described above will doubtless require the structural analysis and blessing (official seal) of a Civil Engineer--money well spent. Anyway, while your existing garage may or may not be strong enough to support a concrete roof, you have to remember that the self-weight of the roofing system subtracts from the added dead- and live-weight of whatever people, plants, solar panels, and temporary structures you add later. While I'm partial to concrete, I'm thinking pre-fab wood trusses and the standing seam metal roofing you mentioned above would be more than strong enough, and probably the lowest weight/sq. ft... yes, wood-frame CAN meet hurricane codes... Checkout the Gulf Coast 'company' town of Seaside, FL. The whole municipality was essentially built by one developer. It's an entirely wood-frame community--the only concrete is the slabs. Even the multi-story structures are wood-frame w/ metal roofs. They meet all Florida Building Code stds. for HVHZ, and fared well in Hurricane Ivan, and the other bad Gulf hits, 2001-2005. Needless to say, the wood framing makes extensive use of steel straps/brackets. Simpson Strong-Tie and Hilti Corp. come to mind. ... if you have photos to illustrate some of the things you talk about, we could stay with you and follow the meaning. >Hollow-core plank being installed on (cast-in-place? walls) single-family residence... in Illinois, no less!... watch your toes, lol... : (copy/paste URL) http://heartstonebuilders.com/images/CRW_9190.jpg >RE: FOLDED PLATE roof... while this method would definitely give you the most STYLISH garage in town, it would seem to be contrary to your desire to have a useable surface, since it is basically like having MULTIPLE PITCHED ROOFS in series: http://populuxebooks.com/blog/media/houseplan1.jpg http://parkimperialsouthps.com/wp-content/uploads/2010/06/17.jpg http://www.columbia.edu/cu/gsapp/BT/BSI/SHELLS_BM/concrf-1.jpg >Double-tees joined to concrete walls: (copy/paste URL) http://www.cpci.ca/images/sectionpics/products_systems/dt_2.jpg PS: Note the CRANES req'd for pre-cast concrete solutions... reportedly a significant cost factor. Here is a link that might be useful:

Here is my post earlier this week on MoccasinLanding's Hardwood Floors thread, with edits: Remember DH's declaration that we won't do any more major projects for the next three years following last year's 5 month and $30,000 foundation disaster? Well, we barely made it a year. The roof is really really really bad, the guys who cleaned my gutters said. We are looking at tearing off the 34 yo shingles, replacing some decking, doubling the amount of soffit vents and adding roof vents. We also may be removing all the decking from the area above the family room in order to insulate above the raised ceiling (it is sooo hot in there in the summer!). Fun fun fun. Last year's foundation disaster almost resulted in us pouring a "porch" foundation the same height as the foyer/laundry room for another 15 ft out from the front door so that when we re-roofed, we could extend the roof out over the porch to the end of the front room, which is DH's library and music room. Doing that, we could add a peak above the foyer and laundry room to change the path of the roof drainage. Then we just need to have Jim move the front wall out and drywall the new side walls and we would get a front closet and a laundry room big enough to work in. Didn't do it. (When I say "almost resulted in," it means that Jim (my contractor) and I were contemplating. DH was never on board.) Kick kick kick. Instead, we will continue to have a flat area on the roof above the foyer and laundry room and just hope that improved ventilation stops the snow from melting or sliding down the roof and icing up my porch and ramp. Stupid house designer must have been from the South. Who makes a roof designed to dump rain and snow in three different directions onto the FRONT PORCH in a cold climate! If we had extended out the front slab, we would now be adding a roof peak where the flat area is and the roof would drain to the sides. And I would have a laundry room big enough to fold in, and a front closet. We do have a coat closet in the middle of the house. It could be a utility closet now instead, if we had poured that slab out further last year......... My shins hurt. Friday, December 14 Yesterday I signed a contract to redo the roof. Today I stopped by their office to drop off a check for the first half of the payment. I talked with the manager and we discussed the venting further and the possibility of putting insulation above the cathedral ceiling in the family room. There was no way to get up there to insulate when we had the attic insulated because there was not enough room between the ceiling and the roof. So he will pull up some roof decking to check out the condition of the insulation there before re-roofing. He says that if we do need to insulate the room from above, he will do his best to make it fold into the cost of the roof job as much as possible, maybe just paying for the extra materials and a bit more. So that is the not-so-exciting news, we are getting a new roof. The picture you see below is from 2007, before we put in our front door, raised porch deck and ramp. We no longer have any shutters and the front windows have been replaced by Eagle windows with bronze aluminum cladding. The picture in the link has the new garden bed, door, and porch in it, but not the new windows. Here is a link that might be useful: A view of the front of the house with flat roof area

Here is a general reference for flat roofs on homes if it applies to your situation. I've designed these roofs for large hotels, hospitals, dormitories, apartments and offices where cost could be justified by longevity so they were very expensive. I did a study of roofing systems for the State Dept. years ago but they were all on concrete slabs with equipment enclosures. None of them drained by scuppers or gutters except for overflow. Gravity draining to the exterior puts you into a special category that, to my knowledge, is not well documented. I would use a fully adhered or loosely laid single ply membrane and pay careful attention to venting if the structure is wood. You might consider a hipped roof with a slope of 1"+/- in a foot with fully adhered single ply membrane rooting over a recovery board over foam insulation board with perimeter gutters. It would appear flat from the ground.

I know nothing about structural engineering, but I'd say that if you really want a roof over the patio, option B appeals most to me. I think that option A would look really odd. Option C probably would too, with that large a span. Also, from what roofers tell me, every valley you add to your roof bumps up the cost when it's time to re-roof. I'll take a simple, boring straight roof any day. A straight roof also better if you want to add solar panels later (assuming it faces the right way). With all that said, I'm having trouble seeing any of them as very attractive. I'm no decorator, but in my mind, whatever you put there is going to close up the house and make it look less welcoming. That patio is 374 square feet. It'd be a little tight, but a single person good at planning could probably live with reasonable comfort in that much square area. Honestly, I think you may have made the patio too big to have a roof.