IRC Table R404.1.2(8) versus Tables R404.1.2(2,3,4)?

[Jc67roch]

Hoping others out there can clarify this question for me. It appears to me that IRC Table R404.1.2(8) repeats the information/guidance from Tables R404.1.2(2,3,4) HOWEVER provides different numbers/values? For example for an 8" flat concrete basement wall 9 ft in height with 9 feet unbalanced fill, GW soils, Table R404.1.2(2) "Minimum Vertical Reinforcement for 8-inch Nominal Flat Concrete Basement Walls" requires #6 bars @ 35". Table R404.1.2(8) "Minimum Vertical Reinforcement for 6- 8- 10- and 12-inch Nominal Flat Basement Walls" requires #6 @ 46" for the same conditions. What gives? These seem like the "same" tables but the numbers don't match up. Any help is appreciated.

 

[le99]

Yes, the feels from the quick glance seem table 4.1.2(8) is the summary of the tables 4.1.2(2-4), but it also lists the requirement for the 12" flat wall, and details of position the vertical bars (see note). If put them side by side, you might notice other differences, but I doubt there is any more than those just mentioned.

 

[dauwerda]

The tables R404.1.2(2,3,4) have a footnote that state the vertical reinforcement is located at the centerline of the wall.

Table R404.1.2(8) has a footnote that states, "Vertical reinforcement shall be located to provide a cover of 1-1/4 inches measured from the inside face of the wall"

I expect that is the difference.

 

[le99]

Oh, I missed that. So table 404.1.2(8) allows for eccentrically loaded walls, while 404.1.2(2-4) are for concentrically loaded walls. Maybe there are other hidden differences not detected yet.

 

[Jc67roch]

Thanks for finding and pointing those out! Yikes, you would think they would make that distinction clearing between the two tables!