[TowerTalk] Tack welding rebar, need howto

David Gilbert xdavid at cis-broadband.com
Sat Jan 4 13:59:06 EST 2014

Yes, the 40 times diameter requirement is more an older rule of thumb, 
but it still shows up in many (probably the majority) of the references 
I found.  That's why I qualified my comment by saying it depends on the 
application and jurisdiction.  I could have sworn there was a section on 
rebar splicing in the International Residential Code, though, but I 
couldn't find it when I checked last night.

I had to have my rebar cage checked by the building inspector before the 
pour and he signed off on it.  That doesn't mean much, of course, but at 
least the rule of 40 probably has some historical leverage.  The most 
logical way to find out what the local requirement is would be to just 
call the zoning commission and ask.

That pdf file looks like a great reference, by the way ... thanks for 
posting it.

Dave   AB7E

On 1/4/2014 7:52 AM, Jim Lux wrote:
> On 1/4/14 6:02 AM, Patrick Greenlee wrote:
>> A very robust cage you have there, David. Could you site where the 40
>> times diameter is written?  I learned by watching and asking questions
>> of contractors and was told 25 times diameter by more than one and no
>> other value. I will have to look for a reference as I have no alternate
>> experience. Thanks for mentioning 40 as that provides incentive to do
>> some research. Oh by the way... although I demand code or better
>> whenever possible in all endeavors the only inspection I have had
>> building two houses and installing a tower has been by the DEQ
>> (Department of Environmental Quality) who inspect and permit septic
>> systems (my installer was lisc to self inspect.)
> googling "rebar overlap" or "rebar lap splice" turns up a wealth of 
> conflicting information.
> You might look at UBC 1912.1-1912.15
> Apparently the 40xdiameter is an older rule of thumb/code and modern 
> codes vary the length of splice depending on the kind of steel, 
> strength of concrete, application, amount of concrete cover, and 
> spacing of the bars.
> There's also differences depending on the year of the code and what 
> the application is (e.g. rebar in a masonry wall footing might be 
> different than in a flat slab might be different than in a poured 
> concrete wall, etc.)
> Here's a chart
> http://www.monolithic.com/stories/rebar-splicing-and-rebar-sizing
> they talk a lot about complying with code, but don't say which one.
> Here's a whole handbook on splicing:
> http://www.daytonsuperior.com/Artifacts/DS_Rebar_Splicing_HB.pdf
> Page 10 has what you're looking for.
> _______________________________________________
> _______________________________________________
> TowerTalk mailing list
> TowerTalk at contesting.com
> http://lists.contesting.com/mailman/listinfo/towertalk

More information about the TowerTalk mailing list