cantilevered balcony

[geal]

Are there lightweight floor/balcony materials that will help me do the following: I want to extend a portion of my 3rd-floor + mezz condo loft/mezzanine to make a cantilevered walkway/balcony. I want to extend the existing mezz 30inch by 14' loft floor strip[which rests on top of the 9' lower closet "roof" & 5'lower doorway] to include an access walkway so that I can put wardrobes on top of the 30-in loft strip/lower 9'-closet "roof." The loft strip and 9'-closet & 5' doorway are on the each side of a load-bearing wall; that wall supports the 16' ceiling/condo unit roof and that lower closet's front wall ends; the back side of the closet wall supports the other side of the loft strip; the rooms on both sides of the load-bearing wall have 16'ceilings. [ I have a copy of my condo plan, but I couldn't connect it to this message. I've included a web page address of a photo somewhat like what I want]

I'm seeking the "easiest" and/or least expensive way to access that loft strip of space. THANKS
http://www.seattleglassblock.com/images/Floor/sgb_floors_096.jpg

[Rich]

Ummm... your post is a little difficult to follow. Could you do a quick drawing and scan it then email to me. I understand what the final situation will be but I need more detail on what you're starting with (more of the configuration). Or detail from the bottom up what you have in place currently - include what is on each side of the element also.

[Rich]

Ok Geal sent me a layout of his place. Depending on the layout of the joists will depend on the solution. If the joists are running perpendicular to the length of the walkway you can splice joists along side of the existing joists and cantilever them. Typically when cantilevering joists you only want to do this at a ratio of 3:1. So if you extend the joists 6' back along side of the existing joists you can cantilever 2'. I believe there is a maximum.. let me see here.. oh.. yep.. there it is.. if cantilevers are over 24" you should have it engineered. Anyway I'll go on as if that wasn't the case. So extend the joists and use another joist as a rim joist to cap the visible end.
Now if the joists are running parallel to the walkway you will need to cut the existing joists back the 6' or more. You will then need to double up that last joist to support the weight. The joists that you cut will need to be framed back into a double cantilever joists (in other words the 2 sides of the cantilever portion will need to be doubled up). Now do a typical floor framing, as suggested above, with a rim joist.
Finish it off with whatever you like. I hope that answers your question. The railing can be bolted to some blocking placed within the framing. I'll do a quick drawing if it will help explain what I'm talking about.

[Rich]

Ok. I've done a quick drawing showing the two conditions. There is a 3rd that may also work. You could span the 14' with a built-up header (4 2x12's or 3 1/8" x 13 1/2' solid beam) and frame a floor on top of it with 2x6's. The floor would only span the 30" width but would no longer be a cantilever. Anyway here is the drawing.
Floor Framing (http://www.construction-resource.com/images/temp/joists.jpg)

[Rich]

Here are the images of what geal is up against.
Loft Walkway (http://www.construction-resource.com/images/projects/pic1.jpg)
Walkway 2 (http://www.construction-resource.com/images/projects/pic2.jpg)
Walkway 3 (http://www.construction-resource.com/images/projects/pic3.jpg)
Walkway 4 (http://www.construction-resource.com/images/projects/pic4.jpg)

[Rich]

Well after getting some more pictures and information it looks like geal is going to have to use the 3rd method. There isn't a floor on the backside of the wall - it's a lofted ceiling from the floor below.
One good thing with spanning the distance and framing a new floor is it will give you more flexibility on how wide you can make the walkway.

[geal]

On 12/16 you wrote: There is a 3rd [solution] that may also work. You could span the 14' with a built-up header (4 2x12's or 3 1/8" x 13 1/2' solid beam) and frame a floor on top of it with 2x6's. The floor would only span the 30" width but would no longer be a cantilever...???

Then on 12/17 you wrote:One good thing with spanning the distance and framing a new floor is it will give you more flexibility on how wide you can make the walkway.

Could you please sketch the third method. If I am able to adjust the width without a cantilever, would I be framing a support wall for the extended area??

Thanks

[Rich]

Give me just a few minutes.

[Rich]

Ok here (http://www.construction-resource.com/images/projects/balcony.jpg) is a drawing for you. I guess you would be limited by the depth of the railing wall somewhat. If you remove the existing balcony completely you could put the beam where it's shown in the drawing. Then you could cantilever over that another 2'. In essence the depth of the new balcony could be whatever the distance from the wall to the end of the railing wall is plus 2'.