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Rebar in Foundation Forms

Someone in my office was doing a plan review and zeroed in on a typical foundation wall detail which showed a new wall doweled into an existing with #4 bars 2' on center vertically. He questioned the size of the bars which the architect had detailed and the spacing. I think the detail was fine and I believe he is just nit picking but I was wondering where that detail even came from. I searched ACI-18 and a couple of other ACI. references and also the building and residential code and couldn't find. I am in NYS on Long Island but don't think this matters. (just for my knowledge would like to locate) anyone know where to find that common detail for new foundation wall to existing?
 
Many designers, including Architects and Engineers, will use the last details that got approved, enen if they nothing to do with the project at hand.many Architects, including Frank Lloyd Wright, had no clue about details. Ever one of his buildings leaked . many had structural issues, including falling water.
I scrutinized Architects details more than homeowners details, they should know better.
 
Thanks for the feedback. I really didn't want to ask the architect unless I couldn't find it first on my own. It's such a common detail I though someone out here knew off hand. There must be a concrete manual that has it
 
Most architects have no business showing details with reinforcement. They are better served hiring an engineer.

The plan checker checking structural issues should either be a licensed engineer or working under the supervision of a licensed engineer. That is the intention of the law in California. Such an individual would be in a better position to make the decision to say nothing or to ask the architect to document why it complies with the code.

There is no standard detail for this situation. The appropriate reinforcing is highly dependent on what forces are being transferred. In situations where the forces are low the minimum temperature reinforcing required by the code often governs. That said #4 @ 24" o.c. is low.
 
Assuming a structural connection is not required, the dowels tie things together and might help keep the walls together if there is any differential settlement or movement at the joint. If this is the case, I bet some engineer stuck his thumb in the air to see which way the wind was blowing and said #4 @ 24" looks good to me.
 
I searched ACI-18 and a couple of other ACI. references and also the building and residential code and couldn't find.
Did you mean ACI - 318?
2015 IRC
R404.1.3.3.7.8 Construction joint reinforcement.
Construction joints in foundation walls shall be made and located to not impair the strength of the wall. Construction joints in plain concrete walls, including walls required to have not less than No. 4 bars at 48 inches (1219 mm) on center by Sections R404.1.3.2 and R404.1.4.2, shall be located at points of lateral support, and a minimum of one No. 4 bar shall extend across the construction joint at a spacing not to exceed 24 inches (610 mm) on center. Construction joint reinforcement shall have a minimum of 12 inches (305 mm) embedment on both sides of the joint. Construction joints in reinforced concrete walls shall be located in the middle third of the span between lateral supports, or located and constructed as required for joints in plain concrete walls.
Exception: Use of vertical wall reinforcement required by this code is permitted in lieu of construction joint reinforcement provided the spacing does not exceed 24 inches (610 mm), or the combination of wall reinforcement and No.4 bars described above does not exceed 24 inches (610 mm).
 
Did you mean ACI - 318?
2015 IRC
R404.1.3.3.7.8 Construction joint reinforcement.
Construction joints in foundation walls shall be made and located to not impair the strength of the wall. Construction joints in plain concrete walls, including walls required to have not less than No. 4 bars at 48 inches (1219 mm) on center by Sections R404.1.3.2 and R404.1.4.2, shall be located at points of lateral support, and a minimum of one No. 4 bar shall extend across the construction joint at a spacing not to exceed 24 inches (610 mm) on center. Construction joint reinforcement shall have a minimum of 12 inches (305 mm) embedment on both sides of the joint. Construction joints in reinforced concrete walls shall be located in the middle third of the span between lateral supports, or located and constructed as required for joints in plain concrete walls.
Exception: Use of vertical wall reinforcement required by this code is permitted in lieu of construction joint reinforcement provided the spacing does not exceed 24 inches (610 mm), or the combination of wall reinforcement and No.4 bars described above does not exceed 24 inches (610 mm).

That's the code section......I believe I had seen that section but overlooked it since I though it referred only to new connections between intersecting walls. Can't find any other reference that satisfies the joint connection detail that I was specifically looking for (new to old) but this works for me
 
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