Replies

1. 
   DanH | Apr 29, 2016 07:47am | #1

   Is this, as the image implies, an A frame?  If so then the roof load situation is entirely different from "normal".

1. 
   user-2887753 | Apr 29, 2016 11:13am | #3

   Howdy Dan,

      No, it has a 30'X32' space below,(See attached: "Ground_Floor.JPG" Picture of basic ground floor layout , no windows or doors) the 30' walls are reinforced every 10'  with 4X6 posts, the corners are made with  a 4X8 posts laping over a 4X6, and K brace, All the posts are blocked beneath the subfloor to carry load to the foundation.. The 32' walls have 2 4X8 posts sistered at the mid point, with a 12X12 beam suported at 4 points by 8X8 posts (also blocked beneath subfloor)

     Because my laptop is kinda whimpy, I have to do my cosmetic design first, then disect it and do the structura details by section, then put 2 sections together at a time to make sure they grok, so I didn't have this info in the first image.

     My main roof pitch is 67.5Deg, which gives me 3 habitable floors and an attic, so ground floor is shop space, 2nd is first floor of living space, 3rd floor has "open to below" space over living room.

   
2. 
   Mike_Mahan | Apr 29, 2016 09:40am | #2

   Balloon Frame.

   Two story walls need to be balloon framed. Windows or not.

1. 
   user-2887753 | Apr 29, 2016 11:44am | #4

   Howdy Mike,

      Ya know, I have one actual, physical vocational textbook on carpentry to reference (aside from the web) and though I have read the chapter on Wall Framing Systems at least 3 times all the way through, and referenced it a lot on this project, It was not until you posted this response that I was able to go back, reread that section, and see in the section about Platform Framing where it does in fact say "all wall frames are one story tall". But, and I hope this doesn't come across as argumentative, technically this does not imply (at least as far as I can tell) that one cannot build a multi-storied platform frame, but just that a platform frame only has single storied wall frames, so feasibly you could stack one wall frame on another. And granted, I'm neither an engineer, nor architect, which is why I’ll get an engineer to makes sure everything is sound before I build.

      This whole thing sprouted from the idea of building living space with wood framed portable buildings, in a manner similar to the way some folks are using old (or sometimes new, I guess) shipping containers to make habitats. I like the concept of modular building, but I think shipping containers are just about the most ugly way to do it (personal opinion, to each their own & all that) I figured that with some extra bracing (like the afore mentioned “Load Posts”) I could stack portable building & make a purdy cool and spatially interesting living space.

      THAT said, I plan to keep after the concept of “Platform stacking”, and trying to figure out to reinforce where it needs it so that the goal can be achieved. So now I’m looking to solve the window problem, and I didn’t want to be perceived as stupid, or a smartass,,, or disrespectful. Rather, I believe merely because they aren’t doing it doesn’t mean it cannot be done, and I wanna figure out how to do it.

   Thanks for the comment, it showed me something that had been right under my nose for several years.

1. 
   coonass | Apr 29, 2016 07:02pm | #5

   User,

   I agree with Mike that this needs to be balloon framed, other wise it's a hinge. I would frame with 2x6 and sheath the outside with 1/2 plywood. Also your K braces do very little and I don't understand the post.

   KK

1. 
   user-2887753 | Apr 29, 2016 09:44pm | #6

   Howdy KK,

      With respect to yourself, Mike, and any other folks who weigh in on this thread, Yes, I understand that if it’s not Balloon Framed, then it’s a potential hinge, and though Central Texas is not known for snow loads or seismic activity, we do get our fair share of heavy rains and high winds, so it IS an important factor that will eventually be addressed with structural reinforcement, be it “off the shelf” or custom fabrication.

      To paraphrase a previous statement in response to Mike’s post, I firmly believe that just because it isn't done does not mean it cannot be done, and when it IS done, it can be done in a way that is structurally sound. That's the end I'm working towards.

    As to the other points you’ve raised, yes, I’ve been giving serious consideration to changing the exterior framing to 2X6 and re aligning all studs & Joists to be “inline” , but have been engrossed on the doors and windows, so I haven’t made any changes to the framing as of yet.

      The sheathing could easily be changed to ½” Ply, I’m not sold on the Hardie Sheathing, I just used it because I figured it looked more like stucco.

      The K braces certainly do not offer as much value as a single diagonal brace, but it adds a little, and allows for 82” windows to be located closer to the corners of the ground floor structure.

     The Posts are left over from my “Building Blocks”, they were put in place to allow me to remove the Roof and Trusses above the top plate, to stack another “Building Block” on top (Ref attached image; "Building Block.jpg"), and shunt the extra weight down to the foundation. The concept was basically putting Piers inside the walls.

   
1. 
   coonass | Apr 29, 2016 10:26pm | #7

   User,

   I think Mike is one of those Injunears and I am an old guy who has been doing this way too long. This is not a "Potential" hinge, it is a hinge and the whole wall will vibrated like a drum when the door is slammed. I think your structual guy will tell you the same.

   aPost some pics when you're done.

   KK

2. 
   user-2887753 | Apr 30, 2016 06:13am | #8

   Howdy KK,

      Ok, well that sounds like a drumhead, not a hinge. Though off the cuff my solution would be to put a pneumatic cylinder on the door so it can’t slam, that certainly does nothing if you bump the wall hard when your moving in the couch, or something along those lines, and could turn my 14’ windows into 14’ guillotines – O – death. Ok, so were I to build it as a balloon wall, the stud length from bottom plate on the ground floor to the bottom edge of the rafters where they meet at the peak is JUST shy of 46 Feet, which means I would still have to splice at least 3 studs together in that upper area of what I am going to call the “Gabel Wall”, since it goes all the way up to the peak. So that makes 3 Potential hinges in the longest of the wall studs, and fewer splices as you frame out to either end.

      Now, maybe this is just semantics, I use the term “Potential” because it is not a hinge until it gets a load that causes the fasteners to fail, and that joint, or joint system/array/series buckles. When that happens, THEN I call it a hinge. So I’m not correcting you, that’s just how I perceive it. Anyways, back to the Balloon wall;

      So each splice being a potential hinge, How would using a Balloon Wall make a 18’ (or progressively less) section of vertical wall space less susceptible to deflection from outside forces (the door slam, the couch hitting the door frame, etc), When I would be trading in a perimeter joist made like a header (1/2” ply glued & screwed ‘tween a pair of 2X12s) for straight up Spliced Studs? Actually the studs in that area wouldn’t be spliced until we hit the 16’ mark, and I’d still mortice in a ledger, though there is no second floor in that area, and the floor/ceiling joists are running parallel to that wall?

      I’m attaching another picture of the structure from ground floor to roof peak. Since I suspect the multiple images I’ve attached so far do not really put the whole picture together. When I look at it, I see a single story structure with a roof pitch steep enough to accommodate 4 floors of attic space. So maybe that doesn’t matter, and the Gable walls would be balloon Framed in standardized, tried and true construction, but this is obviously not standard.

      Thanks again for your time & thoughts, everything helps in some way or another.

   -Z-

   
3. 
   catmandeux | Apr 30, 2016 07:42am | #9

   That opening in the 3rd  floor requires a beam, which has to be supported by a post in the middle of that gable wall.  Post can be extended up to the next floor, and support the header above the tall windows.  If that header extends out to the exterior wall/roof, then the entire section of wall that runs 2 stories is not structural, and can be filled in with 16' studs.

   You can think of this as timber framing using regular lumber to build up the post and beams.

   You  can then platform frame the rest up to the peak.

   None of the prescriptive code details for wall construction will apply to those sloped walls/roof.  You need to calculate the loads and reactions at all the joints, and detail the connections. 

   Texas gets more than a fair share of strong winds.  Go here: http://windspeed.atcouncil.org/, and get the winds for your area.  90MPH winds will put a lot of force on any wall sticking 42 ft up.

4. 
   coonass | Apr 30, 2016 01:34pm | #10

   Z,

   You just need to balloon frame 1/2 the wall with the door and window. 16' studs or so?  You are going to nee one of those Injunear fellows to crank out some numbers and conections for sure.

   Would love to see the build in progress pics.

   KK

2. 
   Mike_Mahan | Apr 30, 2016 10:02pm | #11

   Call me lazy but....

   Somehow building a single story wall then building another wall on top of it doesn't seem like the most practical way to build a wall under a cathedral ceiling, especially when there are window openings going throught the hinge. I'd much rather build a 2 story wall flat on the floor and tilt it up, than try to climb up and build a wall on top of a wall. If there is no floor diaphram balloon framing is the best way to go. Balloon framing through a second story floor hasn't been done in my lifetime. Houses used to be built this way without fire blocking. With a 2 story chimney to the roof they'd burn down in minutes. 

3. 
   BossHog | May 03, 2016 08:39pm | #12

   Just a semi-related thought to add -

   For those really long studs, I'd suggest considering PSL or LVL lumber.  They're a heck of a lot straighter and stronger.