# Framing a suspended/floating soffit?



## OuchMyThumb (Jan 20, 2010)

I've got to frame a soffit that projects from wall and isn't supported above or below it. I'd like it to project 2' from the wall and be 1' in height. The longest span will go about 20' in length and needs only to support its drywall and a few recessed cans.

I'm wondering whether I need to to any additional framing to stiffen it up so that the outside has little movement (i.e. - don't want the drywall cracking on me.) I was thinking some diagonal bracing or strapping perhaps? These pics illustrate better what I'm looking for. Anyone care to share any experience with this type of soffit?

Thanks,
Aaron


----------



## Bastien1337 (Dec 20, 2010)

going corner to corner as per your 3d drawing should add lots of strength and help to tie the front end from sagging to badly, should be quite strong in a two' span.

if you can try lagging a framing member back into the studs sistered alongside your cripples. make a break in your back ledger at one of these junctions and continue to run beside it. Use it as a cantilever that way it still wont be seen and will add more resistance against the downward force acting on the front plate


----------



## OuchMyThumb (Jan 20, 2010)

Thanks Bastien. Yeah, I thought about doing that, but it's a remodel so I'd have to cut out the existing sheetrock and since it's an exterior wall, I'd be cutting through the vapor barrier as well and would have to patch that back up. It's a good idea, but I was trying to avoid it.


----------



## Bastien1337 (Dec 20, 2010)

20' long is that the dimension from wall to wall or from where one of the bulkheads meets the other one that spans the back wall? its the span that concerns me the most not the projection. longest 2x4 16'? splice on the middle could be weak point.


----------



## OuchMyThumb (Jan 20, 2010)

It looks like the span from wall to the adjacent bulkhead would be just under 17'. I'd just keep any splices toward the end and perhaps reinforce them with a mending plate or sister them from behind.


----------



## griz (Nov 26, 2009)

Try some heavy steel brackets/gussets lagged to the wall.

I failed to attend the levitation class when it was offered.:furious::w00t:


----------



## Joe Carola (Jun 15, 2004)

OuchMyThumb said:


> I've got to frame a soffit that projects from wall and isn't supported above or below it. I'd like it to project 2' from the wall and be 1' in height. The longest span will go about 20' in length and needs only to support its drywall and a few recessed cans.
> 
> I'm wondering whether I need to to any additional framing to stiffen it up so that the outside has little movement (i.e. - don't want the drywall cracking on me.) I was thinking some diagonal bracing or strapping perhaps? These pics illustrate better what I'm looking for. Anyone care to share any experience with this type of soffit?
> 
> ...


Install angled 2x4's like you would when framing a Pent Roof. Or you can use plywood gussets.


----------



## detroit687 (Sep 4, 2008)

I would just build box beam headers out of 3 5/8 metal stud and track fastest easiest and straight as a arrow 25 guage should be fine


----------



## Gough (May 1, 2010)

detroit687 said:


> I would just build box beam headers out of 3 5/8 metal stud and track fastest easiest and straight as a arrow 25 guage should be fine


 
That was my initial reaction as well. Around here, a lot of soffits get built with metal studs and track, often the only steel framing in the house. It's light and it's straight, and it's a lot easier to build the frame on the ground.


----------



## FramingPro (Jan 31, 2010)

Joe Carola said:


> Install angled 2x4's like you would when framing a Pent Roof. Or you can use plywood gussets.


that's what i was gonna say:shifty:


----------



## 3bar (Jan 14, 2011)

why not just nail 2x12 blocking next to the studs, with a continuous 2x12 for the face?


----------



## dprimc (Mar 13, 2009)

I'd definitely add some ply to stiffen things up and span the framing joints. I'd also add some diagonals running from front bottom edge to the back at the top (ideally connecting to sides of the wall studs) That, along with the ones Joe suggested would make a nice 'X' inside, out of the way of your cans, of course.

Make sure all your connections are solid (screws and lags) and I think you'll be alright. :thumbsup:


----------



## dprimc (Mar 13, 2009)

Like this:


----------



## 38eric18 (Jan 29, 2011)

detroit687 said:


> I would just build box beam headers out of 3 5/8 metal stud and track fastest easiest and straight as a arrow 25 guage should be fine


This is the perfect time to use metal framing, especially since the walls are already rocked. I would build it like my drawing below. 

You can quickly screw off all the track to the walls, then pre-assemble the c-shaped sections on a bench, with a jig. Next screw the pre-assembled c-shaped sections into the track, and finish up with L metal on the outside corners. 

I personally would use 22ga steel although 25 would probably be sufficient. I also drew it w/ 3 5/8" studs/track and 2 1/2 would probably be fine for such a small soffit. Finally if there is any doubt about the assembly sagging its supper easy to add a diagonal on every other stud.


----------



## Ashcon (Apr 28, 2009)

I know its too late the job is probably already done but I would use 

plywood extending from the inside the stud wall to edge of the bulkhead. 

1/2" or 3/4" plywood cut in 12" x 28" rectangles will give you the shape 

and when screwed to the wood studs inside the wall will keep everything 

from sagging.:thumbsup: Use wood or metal framing to fill in in between the 

plywood once boarded you could stand up there. 

Hope it worked out Chad


----------



## detroit687 (Sep 4, 2008)

38eric that is not how that should be framed, it should be a continuous box beam header from end to end clips on both sides. A box beam header is two studs two pieces of track. Each stud is stood up in the track like a joist. The track caps the two studs on the top and the bottom is capped of with track. The rest of the soffit can be infilled. You can build the header to any length by stagering the studs in the track, pan head every foot across the track. This should be put together on the ground hung boarded and beaded within one hour. Every load bearing header framed with metal studs is built by using a boxbeam header. I wish I had some cool program like you to draw this out. You don't need a laser or string a line the header will be perfectly straight. Shoot some bench marks to find your elevation for your clips and screw the header off. As far as 25 gauge studs go built like this I weigh 230 and could do pull ups in the center of it with no deflection at all. And honestly if I had to build it out of wood even though this screams metal studs, cheaper, faster , straighter. If I were to frame it with wood I would use a lvl or paralam that spanned the whole length. If I was being cheap I would make it b gluing it up myself with layers of 3/4 ply. And that's exactly how I make stringers, laminated layers of 3/4 ply because it don't shrink. If your not using lvls and god forbid your using green lumber or fir or pine two by guess where your lumber is going to shrink. Right at the top point of the rise. Then you got slanted treads. I'm getting a little of topic but using metal is by far the best way and a boxbeam header would make it structual.


----------



## detroit687 (Sep 4, 2008)

This is a pic off google of a box beam header. The rest of the soffit should be built wasting as few materials as possible. Infill with 2 foot centers with 1 5/8 studs or what Evers cheapest wood studs and track


----------



## Deckem (Jan 27, 2011)

Any time you do a self supporting of floating structure like this and are going to install angle braces, the braces should go from bottom (of the structure or wall attachment) to the top outter end of the floating item.
You want the stress to be transfered to the supporting wall. If you put the braces the opposite way, the force (gravity) is pulling away from the supporting structure.


----------



## Dirtywhiteboy (Oct 15, 2010)

detroit687 said:


> 38eric that is not how that should be framed, it should be a continuous box beam header from end to end clips on both sides. A box beam header is two studs two pieces of track. Each stud is stood up in the track like a joist. The track caps the two studs on the top and the bottom is capped of with track. The rest of the soffit can be infilled. You can build the header to any length by stagering the studs in the track, pan head every foot across the track. This should be put together on the ground hung boarded and beaded within one hour. Every load bearing header framed with metal studs is built by using a boxbeam header. I wish I had some cool program like you to draw this out. You don't need a laser or string a line the header will be perfectly straight. Shoot some bench marks to find your elevation for your clips and screw the header off. As far as 25 gauge studs go built like this I weigh 230 and could do pull ups in the center of it with no deflection at all. And honestly if I had to build it out of wood even though this screams metal studs, cheaper, faster , straighter. If I were to frame it with wood I would use a lvl or paralam that spanned the whole length. If I was being cheap I would make it b gluing it up myself with layers of 3/4 ply. And that's exactly how I make stringers, laminated layers of 3/4 ply because it don't shrink. If your not using lvls and god forbid your using green lumber or fir or pine two by guess where your lumber is going to shrink. Right at the top point of the rise. Then you got slanted treads. I'm getting a little of topic but using metal is by far the best way and a boxbeam header would make it structual.


 Man I hate steel but on this one steel is good;:"/>< I've done a lot of em this way, I do it a bit different but comes out the same! i use hat metal and strings and L metal


----------



## Big Shoe (Jun 16, 2008)

I would go with a 3/4 ply rips screwed and glued to 2x4's to make beam for the face, spanning the length you want. 

Good luck.


----------

