Exterior Wall Removal for Addition

[jordanharms]

Hi all, new here but hoping someone can give some good advice. We are putting and addition on our existing single story ranch house, and I'm trying to figure out how to go about removing the exterior wall. The addition will be just over 20' wide, and I want to be able to remove the entire wall into the new addition. In the picture, the wall in red. The existing trusses rest on this wall, so I need to figure out how to support those. The roof on the new addition does tie in to the existing roof, so I may get some support from that, but would like any feedback on how to go about this.

 

[Snoonyb]

Take your plan, fully dimentioned, to a structural engineer.

 

[nealtw]

The cheapest way is to cut the tails off the rafters or trusses plumb with the wall to be removed. install a girder truss right beside that and hang the old rafters or trusses off that.
You would have the local truss company design that.
The will need the slope of the original roof ( rise over 12" ) and the heal height the distance between the top of the wall and the bottom of the sheeting plumb up from the outside of the 2x4s in the wall or if you have trusses the obvious heal that might be there.

This could be done with a beam but much more expensive and you will want to go with a truss system anyway and they will also build the valley set to go onto the old roof.

When you do the new foundation you will need a bigger footing in each of those corners for the extra point load, that is usually the job of an engineer to figure out size.

 

[nealtw]

Like this.

 

[jordanharms]

Awesome, that's exactly what I'm looking for. So, to further explain my project, the builder we are using didn't have correct information, and built the addition without a girder truss. He didn't realize we were planning to remove the entire wall. So, the stage I'm at is that I have the addition built, with only tar paper on the roof, and wrap on the outside. Is my best bet to have him tear the roof out, and install a girder truss now? Other than it not being there, everything is exactly as shown in the example above. Could the truss be built inside of the roof, or is that a bad idea?

 

[nealtw]

Awesome, that's exactly what I'm looking for. So, to further explain my project, the builder we are using didn't have correct information, and built the addition without a girder truss. He didn't realize we were planning to remove the entire wall. So, the stage I'm at is that I have the addition built, with only tar paper on the roof, and wrap on the outside. Is my best bet to have him tear the roof out, and install a girder truss now? Other than it not being there, everything is exactly as shown in the example above. Could the truss be built inside of the roof, or is that a bad idea?

better late than never. If you have used trusses the same company can make the girder, it will have no tails so you could cut plywood on one side and slide it in. It will likely be 2 ply and will have to nailed together.
Usually you pull nails and slip in hangers but if you have a truss there now that will be tricky. You could build a temp wall inside the house and remove the wall so you can put hangers in. If the old roof has rafters not trusses then the roof has to be supported too. That just two temp walls one for the ceiling and one for the roof.

And you may want to underpin those corners for the extra load because now you have all the weight of the main roof too.

 

[jordanharms]

That makes perfect sense. The old roof has trusses, so shouldn't be a problem there. And there isn't a truss directly at the edge of the wall, so I think it'd be pretty easy to get it slipped in and hangers attached. And yes, definitely better late than never. Thanks for the inside on this, it's helped to put my mind at ease about how I'm going to do this.

 

[nealtw]

Not a problem, I am sure your guy would have come with a similar plan, you could do it with a beam but it would be 5 /12 x 14 or bigger, more money and would want to be engineered.
The truss company engineers everything anyway.

 

[nealtw]

That makes perfect sense. The old roof has trusses, so shouldn't be a problem there. And there isn't a truss directly at the edge of the wall, so I think it'd be pretty easy to get it slipped in and hangers attached. And yes, definitely better late than never. Thanks for the inside on this, it's helped to put my mind at ease about how I'm going to do this.

BTW, the girder does not have to be full height as the roof is already built with out it. So a lower girder will require less plywood to be cut.
I would have it built flat top about 3 ft high and a few inches short for an easy install.
They might call it a Truncated girder