Jun 12, 2007 · 4" cmu might be typically used for small closets or small chases where it is braced by other CMU walls at close intervals. I would be inclined to go to 6" CMU for other applications. The Architect might be thinking of the old empirical method where you could go up to 24 times the thickness = 8 feet max. height.

Jul 26, 2006 · 8" cmu can be designed to heights in excess of 20' The 13'-4" height is based on unreinforced grouted masonry with h/t = 20. For reinforced masonry, 16'-8" was the maximum height(UBC). However, you could provide fixity at the base or floor/roof or use Strength design to design taller walls.

Aug 31, 2004 · The 4" from the Jim Amrhein book is an example of what may be done with 4" block and the international designers may have studied from him or attended seminars and caused the local use of masonry. They did use 6" on many highly loaded walls and switched to 4" for some interior bearing walls to replace the 6" poured walls on high rises.

Feb 11, 2015 · It is damn near impossible to get any reinforcing or anchor bolts in a 4" CMU block. 6" yes, 4" no. You can also use an 8" shoe block (an L shaped block). That would be much more practical and would allow for reinforcing. Can you get away with a 2x4 wall and still meet insulation requirements?

Dec 30, 2009 · 8" CMU Block X 18 = 144" [or 12'-0"] The question I have is I would like to achieve greater heights by grouting vertical reinforcement in the block cores however I am not sure what the design procedure is. I was browsing through the Masonry Designers' Guide however they seemed to just briefly explain the concept rather than the procedure.

Jan 7, 2011 · A masonry block wall can be constructed up to 8’ in winds up to 35mph winds during the initial period. The initial period in the first working day and the intermediate period is any time after the first working day until all structural elements are in place as designed. Say you were constructing a 21’ wall, 8” 125psf CMU’s w/ S type mortar.

Nov 1, 2012 · I am designing a 45ft high 8" partially grouted cmu block wall (#4 @ 48"). I will have spandrels every 10ft to transfer wind load from CMU wall to steel columns. I specified a max deflection of the columns at h/240 and a max deflection of the spandrels at l/600. The steel columns are moment...

Jun 21, 2006 · The existing wall varies from 8'-10' in height and is constructed using regular block in running block. The cores appear to be in reasonable alignment. It is a regular CMU wall, albeit very lightly reinforced. It was originally a residential structure built to a pre-1980's code.

Jul 18, 2006 · I typically place it 8.5"-9" from each face. I keep the bars sizes down also, but will go to a #7 if I am using 12" cmu. Durowal makes rebar positioners that are often used. I have seen two bars per cell specified in 8" block, but coming from a masonry background, I have never seen this installed as intended.

Apr 28, 2014 · Very often a "standard" 4" CMU cannot even be grouted because of the common core configurations. Whatever CMU thickness you use, make sure the core configuration you specify is available for the thicknesses and bonding. Dick Engineer and international traveler interested in construction techniques, problems and proper design.