[Jamnjasper]

I have a barn style home with a gambrel roof. Currently I have a carport (attached to the house, no break in shingles) that I would like to close off then remove part of the barn wall. The wall consists of 6x6x10 posts every 11'-7" with 2x4x10 stud walls separating them. my question is can I remove 8 feet from the ground of the stud walls (not 6x6) without any major consequences

 

[Nealtw]

So usually when you have posts, you would also have beams. If the beams where designed to take all the weight. Then you might not be dealing with a load bearing wall.
So the question is about the beam above the posts.

 

[Jamnjasper]

So above the 6x6s are two 2x4s that end on th posts but are also attached to the stud walls

 

[Nealtw]

So above the 6x6s are two 2x4s that end on th posts but are also attached to the stud walls

That won't help much.
Can you see what is above the 2x4s sitting on top of the 6x6s

 

[Jamnjasper]

The 2 2x4s above the 6x6s support the second floor and the gambrel roof

 

[Nealtw]

The 2 2x4s above the 6x6s support the second floor and the gambrel roof

I understand that, just trying to figure out why you have posts.

I have not got experience with a mansard roof so best we wait for others to add thoughts.:vs_cool:

 

[WillK]

If understanding you correctly, it doesn't matter if you take out 2', 4' or 8', what you're doing is leaving a hole in the load path for the second floor structure, so you need to have a beam to transmit that load to the side and just as you would if you put a window or a door in a load bearing wall, that beam needs to have jack studs under the end.

Hypothetically speaking, you could contain that beam within the remaining 2' of wall that you're leaving when you take out the bottom 8'.

I would strongly recommend involving a structural engineer to size the beam and support system. I am an automotive engineer so I'm generally familiar with the concepts, but I'm not licensed and my opinion should have no more weight than any other random person on the internet, so don't only take my word, do your own research and let a licensed qualified professional be the final word.

Looking at the span tables from IRC table R502.5(2) if you're trying to span 11'9 to support load from a roof, ceiling and 1 story above, you go all the way to the max beam they list in the table and you need to construct your beam from 4 2x12 boards that are supported by 2 jack studs. And it only works if your building width is 20' or less, if it's wider and you go to the 28' column then the table does not list a large enough beam. If I was considering that option, I'd start thinking about getting someone to look at it that knows what they're doing or I'd consider alternatives like mid-span support.

This of course assumes adequate support at the bottom, if it's over a footer wall you might be fine, if it's over slab probably not.

An engineer would be able to specify other options besides built up beams from 2x lumber, most likely something smaller that wouldn't be wider than your 2x4 wall studs. Possibly a steel beam or LVL.

 

[SeattleTim]

New related question here: I have a load bearing wall that used to be a 2nd floor condo exterior wall between a living room and covered patio that a prior owner framed out and turned into a sunroom. I took out the door and window between those rooms and all that is remaining in the 8' wide span is the 3 sistered 2x4s at 2' into the span that framed between the window and door. There is an existing 4x12 solid timber beam of unknown species and grade (but tons of grade 2 douglas fir used here) that runs that 8' span, might continue further into the condo supporting the kitchen area, that is secured to an exterior vertical wood load post just outside where the window was and an interior vertical wood load post that was the interior frame aspect of the doorway. Above is one more condo living space and a trussed roof, and a covered patio above my sunroom. This is Seattle so no snow load to figure in. There was no other vertical framing in the wall, just the doorway and window with sill wall below, so it appears that beam was already handling all the load, and I'd doubt those 3 sistered 2x4s between the door and window added much structural vertical load support. Just wondering if anyone can confirm it makes sense those 3 2x4s were simply for door/window framing and not vertical load support at the 1/4 point of the width of the 8' beam span. If it needed vertical support in the span I would have expected to find a solid post. If my assumption is correct I can remove them and not really lose much of any support and the beam should carry it. Thanks in advance for experienced opinions.

 

[Nealtw]

New related question here: I have a load bearing wall that used to be a 2nd floor condo exterior wall between a living room and covered patio that a prior owner framed out and turned into a sunroom. I took out the door and window between those rooms and all that is remaining in the 8' wide span is the 3 sistered 2x4s at 2' into the span that framed between the window and door. There is an existing 4x12 solid timber beam of unknown species and grade (but tons of grade 2 douglas fir used here) that runs that 8' span, might continue further into the condo supporting the kitchen area, that is secured to an exterior vertical wood load post just outside where the window was and an interior vertical wood load post that was the interior frame aspect of the doorway. Above is one more condo living space and a trussed roof, and a covered patio above my sunroom. This is Seattle so no snow load to figure in. There was no other vertical framing in the wall, just the doorway and window with sill wall below, so it appears that beam was already handling all the load, and I'd doubt those 3 sistered 2x4s between the door and window added much structural vertical load support. Just wondering if anyone can confirm it makes sense those 3 2x4s were simply for door/window framing and not vertical load support at the 1/4 point of the width of the 8' beam span. If it needed vertical support in the span I would have expected to find a solid post. If my assumption is correct I can remove them and not really lose much of any support and the beam should carry it. Thanks in advance for experienced opinions.

I did not read it all. You are in a condo, you need an engineer so you don't get sued. I am surprised any exterior work could be done.

 

[SeattleTim]

Thank you for the reply. Yes, that is certainly a strong consideration and some words of wisdom. Even with that in mind, my thought was since the only vertical lumber under that 8' span was the 3 sistered 2x4s between the door and window, would common construction knowledge consensus be that those 2x4s were strictly framing and not a load bearing vertical support. Sure, anything vertical technically adds some support, but I'd think when it was originally engineered and approved in initial construction when it was a patio outside that wall, if it needed support in that span a 4x4 post at the least would have been required, not 3 sistered 2x4s. Thanks.

 

[Daniel Holzman]

The only way to determine if a given wall is load bearing is by a hands on investigation to determine what load, if any, the wall is supporting. You cannot do the work over the internet, and photos only go so far. You need to open up the space above the wall to see what the wall is holding up.

 

[Nealtw]

Thank you for the reply. Yes, that is certainly a strong consideration and some words of wisdom. Even with that in mind, my thought was since the only vertical lumber under that 8' span was the 3 sistered 2x4s between the door and window, would common construction knowledge consensus be that those 2x4s were strictly framing and not a load bearing vertical support. Sure, anything vertical technically adds some support, but I'd think when it was originally engineered and approved in initial construction when it was a patio outside that wall, if it needed support in that span a 4x4 post at the least would have been required, not 3 sistered 2x4s. Thanks.

Many time they called for 2 separate headers and when room was tight like this where there would be no room for the king stud. one header is used and supported in the same place as if it was two.
So there is nothing there that says anything.

 

[SeattleTim]

The only way to determine if a given wall is load bearing is by a hands on investigation to determine what load, if any, the wall is supporting. You cannot do the work over the internet, and photos only go so far. You need to open up the space above the wall to see what the wall is holding up.

These condos are stacked like boxes so directly above this wall another same wall is built as an exterior wall with a covered patio above my sunroom. Also, I took another look at what is above that upstairs unit and I didn't line things up right on site - the area above the upstairs unit is a flat rooftop deck with waterproofing with wrapped metal sheeting and 1/8" epoxy sprayed/rolled layer - no trussed roof or any other weight. Although people can go up there like a patio, so live load too.


So this 4x12 dimensional beam is taking the weight of the upstairs wall directly above it, half the dead and live weight of the upstairs 9ft wide covered patio, half the dead and live weight of the 12ft wide upstairs living area, and half the weight of a 21' width of rooftop deck.


Assuming this beam shares all weight above, I calculated the tributary or contributing loads, with a deflection limit of L/360, as:
- the upper level wall dead load is 128 pounds per lineal foot
- the 2nd floor living area live load is 30psf X 6ft= 180 pounds per lineal foot
- the 2nd floor living area dead load is 10psf x 6ft = 60 pounds per lineal foot
- the 2nd floor covered patio live load is 30psf x 4.5ft = 135 pounds per lineal foot
- the 2nd floor covered patio dead load is 10psf x 4.5ft = 45 pounds per lineal foot
- the 10.5ft portion of the waterproofed flat roof deck live load is 30psf x 10.5ft = 315 pounds per lineal foot, totaling
- the 10.5ft portion of the waterproofed flat roof deck dead load is 15psf x 10.5ft = 158 pounds per lineal foot
- total load is 1,021 pounds per lineal foot


I just can’t find a table that states the load capacity of a solid sawn 4x12 dimensional beam to know if it can handle the 1,021 plf. Anyone have a link to a table for a solid sawn 4x12 dimensional beam? I didn’t find it in the International Building Code or Residential Code. Thanks.

 

[SeattleTim]

Thanks everyone for the thoughts. Scheduled a structural engineer for next Tuesday to be safe and CYA. Great forum!