I have had several discussions with ICF mfg. about this after several discussions with a supplier/contractor. I think they rely both on testing and section 14.2.4 in ACI 318-05. In addition its use in residential structures.
Joe
Joseph R. Grill, PE
Verde Valley Engineering, PLLC
email: VVEng@cableone.net
From: Richard Calvert [mailto:RichardC@lbbe.com]
Sent: Wednesday, September 02, 2009 2:30 PM
To: seaint@seaint.org
Subject: RE: ACI 318 maximum reinforcement spacing.
ACI 332 (I think), which is geared specifically for residential, allows for much greater spacing.
From: Jeff Hedman [mailto:jeff_h@lrpope.com]
Sent: Wednesday, September 02, 2009 4:49 PM
To: seaint@seaint.org
Subject: ACI 318 maximum reinforcement spacing.
We do not allow any concrete vertical or horizontal reinforcement to be spaced more than 18" o.c. due to the fact that it is listed as the maximum spacing in ACI 318 in multiple places and applications. I am specifically interested in any exceptions to 14.3.5 for vertical and horizontal wall reinforcement. I have a client that is doing an ICF home with a 6" core that he is claiming that he does 24" o.c. spacing all the time. I can't find any exceptions in the code for exceeding the maximum 18" o.c. spacing for walls. Anyone know of any exceptions to the 14.3.5 to space reinforcement farther apart? If not, that’s fine, I’ll stick to my guns. He is so adamant about it that I thought it would be best to ask before letting him know I’m not budging on the reinforcing spacing.
Thanks,
Jeff Hedman