Replies

1. 
   calvin | Sep 19, 2011 08:23pm | #1

   An engineering question I cannot answer........

   but I can tell you this, you need to stiffen the wall for your own benefit as well as that of inspection-if applicable.

   On a scissor trussed, single story gable end addtion I did 15 yrs ago the inspector made a "suggestion".  Get some full length 2x4's in that wall somewhere.  With all the glass, it was not easy, but you understand the point-two pc wall or one made up of headers and bucks don't cut it.  The wind could rattle it or in the unlikely event of a major wind, probably failure.

   Steel might be one way.  Perhaps letting in a portion of an LVL............I frankly have no idea.

   Hopefully someone here has built one, and you'll rcv. some type of answer.  Otherwise, a call to an engineer might not be money mis-spent.

   Best of luck.

2. 
   oops | Sep 20, 2011 09:28pm | #2

   You have not provided enough information to for anyone to give you much help.

   Is this a single story structure with no intervening floors between the groung floor and the ridge 27' above?

    What is the span / horizontal length of the wall? What is the pitch of the roof? What is the height of the side walls? e.g. the short height of the the wall.  Where is it located? What are the maximum winds speeds in the area. ETC.ETC.ETC.                    

   For a wall of this height, you need to think of the studs / vertical members as beams  resisting wind forces as much as columns supporting the roof loads. I doubt very seriously,  that you are talking about standard 2 x 4 or 2 x 6 framing.

   As Calvin stated in his reply to your post, this sounds as if you need the help of an engineer.

   P.S. If I am picturing this correctly, the 2' protusion you mentioned is indeed significant and could be adding a great deal of stiffness.

1. 
   calvin | Sep 20, 2011 10:50pm | #3

   You are right about the prow part.

   It will stiffen that point and divide the wind force while it's at it.

   Depending on how much of flat wall is left on the two sides will give the answer to how much they need stiffened.

   Love the way this place pulls pcs of info out and starts to build an answer.

3. 
   DanH | Sep 20, 2011 11:00pm | #4

   How wide is the wall?

4. 
   hammer1 | Sep 21, 2011 10:27am | #5

   What are you framing the walls out of? Typically, you would use 2x6 studs. Prowl, meaning the wall is V shaped. Build in 8' tall, nominal, sections. Double top plate, next wall section and so on. If the walls are fairly long, you can add a steel flitch plate between the top plates, 1/2" x 5"  flat steel, pre drilled, bolted through.

5. 
   DaveRicheson | Sep 21, 2011 11:51am | #6

   Making a couple of assuptions here based on having help build one brow front home.

   I'm guessing that the wall is full of windows, cause the ones I've seen are oriented for view. Second, since it is a 27' cathedral, you have a structural beam. The outboard end of that beam is going to be supproted by post or multiple studs to the foundation wall. The walls on each side are not load bearing for the roof syste, depending on window configurationsin the two walls, your best bet would be to divide it with a paralam beam bearing on the side walls or tied into them. That serves to stiffen the prow more than stack framing walls on top of walls. Agian depending on widow locations andsizes/configuration a secon parralam could be added above the secound course of windows and tied to a strenghten rafter pair. The rest then becomes stud infills and r.o for windows.

   Agian I saying this all just a SWAG based on personal experience and the little information you have provided. Might be time to get a structural engineer envolved.

6. 
   Clewless1 | Sep 25, 2011 09:28am | #7

   When framing gable end walls in my new house ... my inspector forbade anything but full height stud framing ... no intermediate plates ... the plates create a hinge that under stress will 'fold'. Your prow config is actually a stiffening over doing a flat wall.

   The 27 ft (I assume at the center only) poses a problem ... but you can get stiffness by sistering shorter studs.

7. 
   squarenut | Sep 25, 2011 12:29pm | #8

   Past experience with balooned framed gable walls

   First off, I will say I'm not a structural engineer, and would recommend you speak with one, but I'am a custom home framer and have had some experience working with an engineer on some very tall gable walls full of windows and doors. We used steel flinch plates sandwiched in between two king studs at all the openings as well as between all the headers. That seemed to do the trick quite well.