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General => General Forum => Topic started by: astidham on July 19, 2010, 09:47:00 AM

Title: header question Help Needed
Post by: astidham on July 19, 2010, 09:47:00 AM
Hey all,
I framed a RO for a 6' door on the load side of my cabin and used a 6x6 header, 3-2x6s nailed together.
I cant find a span table for this type of header since I didnt use plywood spacers.
does anyone know of a chart or if the 3-2x6s will span 6'? pictures can be seen under OKLAHOMA 20X30 page 4
Thank You.


Title: Re: header question
Post by: Kevin on July 19, 2010, 10:00:08 AM
Rule of thumb is 1 inch for every foot of span.
Kevin
Title: Re: header question
Post by: dug on July 19, 2010, 10:45:15 AM
On John's plans it says that two 2 by 12's will span up to 5 ft. 6 in., and three 2 by 10's will take you up to 6 ft. 6 in.

Not to hijack your thread, but I happened to noticed that I have a 6 ft. window opening that I framed using two 2 by 10's. I don't know if I just read the plans wrong or got the information elsewhere. I can't remember.

Am I in trouble? Just about anythings is possible, so I suppose I could somehow manage to tear it apart and squeeze in another 2 by 10.

I am not sure what our snow load is here so I have a little trouble trying to decipher the load ratings. In 5 years I have never seen more than 6 in. of snow on the ground though.
Title: Re: header question Help Needed
Post by: Don_P on July 19, 2010, 08:35:26 PM
It depends on several factors. Chapter 5 of the IRC has girder and header tables at the end of the floor joist span tables in chapter 5.
This is VA's online code but the table is pretty universal.
https://www2.iccsafe.org/states/Virginia/Residential/Res-Frameset.html
Title: Re: header question Help Needed
Post by: astidham on July 20, 2010, 09:23:22 AM
Thanks Don_P
Title: Re: header question Help Needed
Post by: John Raabe on July 20, 2010, 09:57:48 AM
Here is a printable version of the most commonly used section of this header chart.

http://www.countryplans.com/Downloads/header-span.jpg

Title: Re: header question Help Needed
Post by: astidham on July 20, 2010, 01:58:50 PM
Thank you John,
when it says 2-2x8, is it referring to 2-2x8s with a plywood spacer or just the 2x8s?
Title: Re: header question Help Needed
Post by: Don_P on July 20, 2010, 04:10:31 PM
Plywood in a typical header or girder adds no strength, it is there for spacing. If properly fastened one can add the strength of the plies that run in the direction of the axis of the beam. If you're cutting it that fine step up a size or use a steel flitch plate. Also don't forget to check the number of jacks required to avoid crushing into the header. In chapter 6 there is a plywood header table if you can follow all the rules and exceptions. There are also specs on building plywood beam assemblies on the APA website, that's getting in deep fast though, just throwing it out there for info.
Title: Re: header question Help Needed
Post by: astidham on July 20, 2010, 07:40:27 PM
thanks Don_P, do you know of a span chart for using triple the wood?
I'm not going to use my 6' opening I framed in because my wife wants the patio door on the other side of the house, but my header for that door was 3-2x6s and i wonder how far that can span. 
Title: Re: header question Help Needed
Post by: Don_P on July 20, 2010, 09:24:32 PM
It's pretty hard to answer a question posed that way, or it all depends, is the beam holding an elephant or just a fat lady  ;D. I don't know enough of the variables.

I can answer it another way, a triple 2x6 in average wood spanning 6 feet can hold around 3000 lbs safely if it is uniformly distributed along the beam, about half that if it is piled in the middle. A single jack at each end under it would be ok at that load.