# Load/Span Data for 2x4 Headers



## Abuc (Aug 28, 2018)

I found tables for dimensional lumber down to 2x6, but nothing for 2x4. The load capacity for a given deflection seems to decrease by the square of the depth, eg a 2x6 has about 25% of a 2x12. I can extrapolate but would like to see actual data. 

What I really want to know is how much lateral strength (resistance to bowing) will a double 2x4 plate give to a 2 ply LVL beam. I figure the header data would be a good approximation.

Thanks.


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## HenryMac (Sep 12, 2018)

This may be helpful to you: https://www.southernpine.com/span-tables/headers-beams-size-selection-tables/


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## Nealtw (Jun 22, 2017)

2x4s are never headers, plates lay flat, headers stand on edge.


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## Abuc (Aug 28, 2018)

Nealtw said:


> 2x4s are never headers, plates lay flat, headers stand on edge.


Yes, I understand that. I am assuming the deflection on a 2x4 header at a given uniform load and span will give me some rough idea on how much a 2x4 plate connected to the top of a 2 ply LVL will stiffen it against a lateral wind load.


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## Abuc (Aug 28, 2018)

HenryMac said:


> This may be helpful to you: https://www.southernpine.com/span-tables/headers-beams-size-selection-tables/


Yep, that is the data I was referring to. Only goes down to 2x6 but looks like I can extrapolate to 2x4 if I can’t find the actual data.


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## Nealtw (Jun 22, 2017)

Abuc said:


> Yes, I understand that. I am assuming the deflection on a 2x4 header at a given uniform load and span will give me some rough idea on how much a 2x4 plate connected to the top of a 2 ply LVL will stiffen it against a lateral wind load.


How long s the LVL, once a double is nailed together they are pretty stiff on there own.


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## Abuc (Aug 28, 2018)

Let me say a little more about my issue. I could have continued my garage header thread but this is a little different animal. Major LVL suppliers, eg LP and Weyerhaeuser, have user friendly apps to design LVL headers for vertical loads. They also let you calculate horizontal deflection for lateral wind loads on single ply beams ONLY. They told me they will not help users design a two ply LVL with a lateral wind load because the math is too complicated and unreliable. They say the only way you can use a two ply LVL exposed to a lateral (perpendicular to beam) load is if it is designed by an engineer. I talked with Simpson about their structural fasteners and they said the same thing. I have learned that it is it a simple task to design a LVL beam for vertical loads but impossible for lateral wind loads.


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## Nealtw (Jun 22, 2017)

Abuc said:


> Let me say a little more about my issue. I could have continued my garage header thread but this is a little different animal. Major LVL suppliers, eg LP and Weyerhaeuser, have user friendly apps to design LVL headers for vertical loads. They also let you calculate horizontal deflection for lateral wind loads on single ply beams ONLY. They told me they will not help users design a two ply LVL with a lateral wind load because the math is too complicated and unreliable. They say the only way you can use a two ply LVL exposed to a lateral (perpendicular to beam) load is if it is designed by an engineer. I talked with Simpson about their structural fasteners and they said the same thing. I have learned that it is it a simple task to design a LVL beam for vertical loads but impossible for lateral wind loads.


Hmm, I didn't put the two threads together. In the other thread I think I did explain that we use a full 2x10 for what would be the door jam, that would add much to the strength,, you also want to look at the height I guess of you are right up close to the roof that would be better than if it was dropped 2 feet. I haven't seen it even considered before, we always put the beam right under the roof and often build down from that to the door height, some times that approaches 4 feet hanging from the beam with a 2x6 wall, but a big wind here might get to 65 mph.


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## 3onthetree (Dec 7, 2018)

Abuc said:


> They say the only way you can use a two ply LVL exposed to a lateral (perpendicular to beam) load is if it is designed by an engineer.


That's because it would be a built-up beam and fastening methods play. Same as you figuring using the 2x4 top plates. I wouldn't imagine there's any info on 2x4s, as Neal said those are not used as headers, only as a part of shear wall systems. I wouldn't rely on extrapolation of the cross-sectional area.


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## Abuc (Aug 28, 2018)

Nealtw said:


> Hmm, I didn't put the two threads together. In the other thread I think I did explain that we use a full 2x10 for what would be the door jam, that would add much to the strength,, you also want to look at the height I guess of you are right up close to the roof that would be better than if it was dropped 2 feet. I haven't seen it even considered before, we always put the beam right under the roof and often build down from that to the door height, some times that approaches 4 feet hanging from the beam with a 2x6 wall, but a big wind here might get to 65 mph.


My 18’ garage door header will be a “drop” beam with a 5’ high pony or cripple wall above it. The cripple wall connects to the bottom chord of the structural truss above it (non load bearing gable end). So, the force from the wind blowing normal to the pony wall will be transmitted to the header and the attic framing. The pony wall is only 90 sq ft so normally not a big deal, but more problematic if you design for 90-100mph. Since none of the software apps will do this calculation for you, you either have to guess or hire an engineer.


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## HenryMac (Sep 12, 2018)

Abuc said:


> I found tables for dimensional lumber down to 2x6, but nothing for 2x4. The load capacity for a given deflection seems to decrease by the square of the depth, eg a 2x6 has about 25% of a 2x12. I can extrapolate but would like to see actual data.





3onthetree said:


> I wouldn't rely on extrapolation of the cross-sectional area.


And that's good advice.


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## Nealtw (Jun 22, 2017)

Abuc said:


> My 18’ garage door header will be a “drop” beam with a 5’ high pony or cripple wall above it. The cripple wall connects to the bottom chord of the structural truss above it (non load bearing gable end). So, the force from the wind blowing normal to the pony wall will be transmitted to the header and the attic framing. The pony wall is only 90 sq ft so normally not a big deal, but more problematic if you design for 90-100mph. Since none of the software apps will do this calculation for you, you either have to guess or hire an engineer.


 Or rebuild the wall out of 2x8 or 2x10, would be cheaper than an engineer. :biggrin2:Can you find similar garages to see what has been done and has past the test of time. Or on the more ugly side angle bracing from above the door to the trusses above.


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## Nealtw (Jun 22, 2017)

I just watched the video on wall bracing for wind by the APA, they show a door similar to yours and say nothing about that wind resistance. 

You could try contacting them with a question. 

https://www.apawood.org/wall-bracing-webinars


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## Abuc (Aug 28, 2018)

3onthetree said:


> That's because it would be a built-up beam and fastening methods play. Same as you figuring using the 2x4 top plates. I wouldn't imagine there's any info on 2x4s, as Neal said those are not used as headers, only as a part of shear wall systems. I wouldn't rely on extrapolation of the cross-sectional area.


For an 18’ span, allowable TL’s are 61, 43, 26 and 11 for 2x12, 2x10, 2x8 and 2x6 respectively. Calculated values using the square of the actual long dimension using the 2x12 as a starting point are 41, 26 and 14. Looks like a pretty good fit to me.


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## Abuc (Aug 28, 2018)

Nealtw said:


> I just watched the video on wall bracing for wind by the APA, they show a door similar to yours and say nothing about that wind resistance.
> 
> You could try contacting them with a question.
> 
> https://www.apawood.org/wall-bracing-webinars


Great videos but they do not address my issue. These videos tell how to have enough braced wall to transfer wind load to shear walls. But, I think your suggestion to contact APA is excellent. Part of their mission is to help end users. I will report back what they say.


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## Abuc (Aug 28, 2018)

Abuc said:


> Great videos but they do not address my issue. These videos tell how to have enough braced wall to transfer wind load to shear walls. But, I think your suggestion to contact APA is excellent. Part of their mission is to help end users. I will report back what they say.


APA responded to my question within a couple hours. They told me product technical info must come from manufacturers. They also said they do not have any guidance for multi-ply LVL beams exposed to horizontal wind loads. 

I talked with my structural engineer and he said he would not recommend a multi-ply LVL beam for a drop down garage door header exposed to wind. He said depending on fasteners for horizontal loads is not good design. However, I could do it safely if I added braces to transfer load to the 2nd story diaphragm. OTOH, my local inspector told me they approve multi-ply LVL beams in this application routinely. Just tie them together with construction adhesive and shoot “lots of nails in it”. Go figure.


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## Mark2020 (Nov 20, 2018)

Abuc said:


> I found tables for dimensional lumber down to 2x6, but nothing for 2x4. The load capacity for a given deflection seems to decrease by the square of the depth, eg a 2x6 has about 25% of a 2x12. I can extrapolate but would like to see actual data.
> 
> What I really want to know is how much lateral strength (resistance to bowing) will a double 2x4 plate give to a 2 ply LVL beam. I figure the header data would be a good approximation.
> 
> Thanks.


Lateral strength on the top? Is the beam being pushed to the side? It adds something... but the question is what about the bottom of the beam? What's pushing on the beam that you need to consider lateral strength?


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## Abuc (Aug 28, 2018)

Mark2020 said:


> Lateral strength on the top? Is the beam being pushed to the side? It adds something... but the question is what about the bottom of the beam? What's pushing on the beam that you need to consider lateral strength?


Wind. I gave up on the 2 ply LVL beam. Going to us a one ply 3-1/2” PSL beam which will take 90 mph like a champ.


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## Mark2020 (Nov 20, 2018)

I've never heard of lvl or psl being an issue for garage header. It needs to carry the vertical load and then enough king studs, properly fastened, to carry the opening.


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## Abuc (Aug 28, 2018)

Mark2020 said:


> I've never heard of lvl or psl being an issue for garage header. It needs to carry the vertical load and then enough king studs, properly fastened, to carry the opening.


There is a 5’ high cripple wall between my header and ceiling. When the north wind blows on that cripple wall if creates a lateral load. Half goes into the attic floor diaphragm and half goes into the header. The header will transfer it to the king studs but will bow under the stress. At 90 mph, a 3-1/2” PSL beam will bow about 1/2” which is completely acceptable. I am sure a 2 ply LVL would be ok too but you can not get the manufacturer to warrant it or give you any technical support. In fact, the Weyerhaeuser Forte app will not even allow you to design a multi-ply LVL with lateral wind load. They said the math was too complicated and unreliable. I also talked with LP and Simpson and they said the same thing. They want zero liability if fasteners fail. No problem predicting fastener performance with side loads, just can’t or won’t do it for lateral loads.


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## Mark2020 (Nov 20, 2018)

Abuc said:


> There is a 5’ high cripple wall between my header and ceiling. When the north wind blows on that cripple wall if creates a lateral load. Half goes into the attic floor diaphragm and half goes into the header. The header will transfer it to the king studs but will bow under the stress. At 90 mph, a 3-1/2” PSL beam will bow about 1/2” which is completely acceptable. I am sure a 2 ply LVL would be ok too but you can not get the manufacturer to warrant it or give you any technical support. In fact, the Weyerhaeuser Forte app will not even allow you to design a multi-ply LVL with lateral wind load. They said the math was too complicated and unreliable. I also talked with LP and Simpson and they said the same thing. They want zero liability if fasteners fail. No problem predicting fastener performance with side loads, just can’t or won’t do it for lateral loads.


Solid width is always better. Multi-ply would require fasteners to transfer the shear forces generated by the moment. That being said... i've spec'd out lvl's all the time for foyer entry, 2 story homes, and never had a problem. On the notes is my fastening requirements for 2 ply. Who knows what they actually nail them together with but after 15 years... no issue yet.

Reason is the builders want to save money. So instead of 2x6 or 2x8 balloon frame they want to keep the 2x4 studs in foyer. I did the calc a long time ago and decided it was ok to transfer all that load through an lvl. Gotta clip the ends good though.


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## viper (Jul 30, 2009)

I am just stepping in here. What are the dimensions you are after? What material properties are required? Allowable deflection? Is this going to be an inspected element by code enforcement?


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## Nealtw (Jun 22, 2017)

viper said:


> I am just stepping in here. What are the dimensions you are after? What material properties are required? Allowable deflection? Is this going to be an inspected element by code enforcement?


There is little to no load from above, the concern is wind resistance with a double 9" lvl.


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## viper (Jul 30, 2009)

Nealtw said:


> There is little to no load from above, the concern is wind resistance with a double 9" lvl.



I am wondering why we need an LVL? I have a few thoughts but I'd like to know the details. Is the LVL the only thing that will fly with the code man? 

I am guessing that a sandwich of LVLs, or any other lumbers, oriented as I assume, will be disconnected at the neutral axis in that direction of lateral deflection. 

Depending on the loads and requirements, there are a few other ways to fix this. I need to know what the allowable wall deflection is.


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## Mark2020 (Nov 20, 2018)

viper said:


> I am wondering why we need an LVL? I have a few thoughts but I'd like to know the details. Is the LVL the only thing that will fly with the code man?
> 
> I am guessing that a sandwich of LVLs, or any other lumbers, oriented as I assume, will be disconnected at the neutral axis in that direction of lateral deflection.
> 
> Depending on the loads and requirements, there are a few other ways to fix this. I need to know what the allowable wall deflection is.


Who's we?

I thought abuc asked the question?


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## Mark2020 (Nov 20, 2018)

viper said:


> I am wondering why we need an LVL? I have a few thoughts but I'd like to know the details. Is the LVL the only thing that will fly with the code man?
> 
> I am guessing that a sandwich of LVLs, or any other lumbers, oriented as I assume, will be disconnected at the neutral axis in that direction of lateral deflection.
> 
> Depending on the loads and requirements, there are a few other ways to fix this. I need to know what the allowable wall deflection is.


lol... really?


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## viper (Jul 30, 2009)

Mark2020 said:


> lol... really?


I don't know what that means but feel free to enlighten me.


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## Mark2020 (Nov 20, 2018)

viper said:


> I don't know what that means but feel free to enlighten me.


this...

"will be disconnected at the neutral axis in that direction of lateral deflection. 

Depending on the loads and requirements, there are a few other ways to fix this. I need to know what the allowable wall deflection is."

I have no idea what that means... from an engineering stand point.


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## Nealtw (Jun 22, 2017)

viper said:


> I am wondering why we need an LVL? I have a few thoughts but I'd like to know the details. Is the LVL the only thing that will fly with the code man?
> 
> I am guessing that a sandwich of LVLs, or any other lumbers, oriented as I assume, will be disconnected at the neutral axis in that direction of lateral deflection.
> 
> Depending on the loads and requirements, there are a few other ways to fix this. I need to know what the allowable wall deflection is.



With out much load from above the need for support is minimal and he will be removing 2x10 headers, full length 2x10 could sag under there own weight. The two ply LVL seems like a good way to go. but then the wind issue came up, the gable should be fine and maybe a few mores 2x4s can be added above the lower members of the trusses, I have seen things done about that. The problem is the beam is some distance below the gable. 

So then you look at the bend sideways in wind or even if it holds stiff the next issue would be the connection of the beam at the ends.


I have ideas that I would discuss with an on site engineer but I would not suggest anything because it is out of my experience.


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## viper (Jul 30, 2009)

Mark2020 said:


> this...
> 
> "will be disconnected at the neutral axis in that direction of lateral deflection.
> 
> ...



It means that two pieces of lumber cannot be stacked to create the same as a single engineered beam.


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## Mark2020 (Nov 20, 2018)

viper said:


> It means that two pieces of lumber cannot be stacked to create the same as a single engineered beam.


ok... will be disconnected at the neutral axis in that direction of lateral deflection. 

Depending on the loads and requirements, there are a few other ways to fix this. I need to know what the allowable wall deflection is.

still lol...


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## viper (Jul 30, 2009)

If you stack two 2x10s on top of each other, where is the neutral axis?


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## Abuc (Aug 28, 2018)

Nealtw said:


> So then you look at the bend sideways in wind or even if it holds stiff the next issue would be the connection of the beam at the ends.


Neal, the Weyerhaeuser Forte app specifies connections required at the beam ends for lateral loads. Toe or end nailing is ok at 90 mph (program gives a nailing schedule). Structural connections are required when you get into the 100-110 mph range.


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## Abuc (Aug 28, 2018)

No worries guys, I have already decided to go with a single ply 3-1/2” PSL beam. The current debate is why beam manufacturers will not recommend a multi-ply LVL beam with a lateral load or provide technical guidance to help someone design one.

I do not believe winds have ever reached 90 mph in this area in my 70 year life time. And, it they ever do, what is the chance it will be normal to my gable wall? I am designing for a case that will never happen, but that is just the way I am wired. I never want to spend two seconds wondering if my multi-ply LVL will stand up to a strong wind.


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## viper (Jul 30, 2009)

Excellent choice! I was on that path but there are a few different options. A glulam could also be an option but I wasn't certain if there was any real vertical loads to tend with.


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## Nealtw (Jun 22, 2017)

Abuc said:


> No worries guys, I have already decided to go with a single ply 3-1/2” PSL beam. The current debate is why beam manufacturers will not recommend a multi-ply LVL beam with a lateral load or provide technical guidance to help someone design one.
> 
> I do not believe winds have ever reached 90 mph in this area in my 70 year life time. And, it they ever do, what is the chance it will be normal to my gable wall? I am designing for a case that will never happen, but that is just the way I am wired. I never want to spend two seconds wondering if my multi-ply LVL will stand up to a strong wind.



Great info and different than seismic most everything we do is craned in micro lam and we get LVLs if we have to place them by hand. :wink2:


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## Abuc (Aug 28, 2018)

Deleted.


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## Nealtw (Jun 22, 2017)

Abuc said:


> Deleted.



There is more to think about. Racking is a consideration, engineers solve that with a nailing pattern on the sheeting on the outside, unless you are stripping siding you don't have that ability.
If you had 2x6 walls the trick is to leave one 2x10 which has the sheeting nailed to it and add the the LVLs inside that and nail the first one to the 2x10.
that's not available either if you are using a beam.
You may want to sheet the inside to tie everything together.


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## Abuc (Aug 28, 2018)

Nealtw said:


> There is more to think about. Racking is a consideration, engineers solve that with a nailing pattern on the sheeting on the outside, unless you are stripping siding you don't have that ability.
> If you had 2x6 walls the trick is to leave one 2x10 which has the sheeting nailed to it and add the the LVLs inside that and nail the first one to the 2x10.
> that's not available either if you are using a beam.
> You may want to sheet the inside to tie everything together.


Great minds think alike. I removed enough 5/8” Sheetrock to inspect the existing framing. No insulation! I was thinking about removing the rest of the Sheetrock to insulate and putting sheathing back up. I am not concerned about racking since that gable wall only projects a foot or so beyond the adjoining room. At one point I was thinking of installing brace panels in the narrrow wing walls to prevent racking but talked myself out of that.


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## Nealtw (Jun 22, 2017)

Abuc said:


> Great minds think alike. I removed enough 5/8” Sheetrock to inspect the existing framing. No insulation! I was thinking about removing the rest of the Sheetrock to insulate and putting sheathing back up. I am not concerned about racking since that gable wall only projects a foot or so beyond the adjoining room. At one point I was thinking of installing brace panels in the narrrow wing walls to prevent racking but talked myself out of that.


Older garages that were sheeted with ship lap rack all the time, we just sheet the inside with osb when we have them straight.


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## Abuc (Aug 28, 2018)

Check this out.

https://www.fpl.fs.fed.us/documnts/fplrp/fplrp448.pdf


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## Abuc (Aug 28, 2018)

Check this out.

https://www.fpl.fs.fed.us/documnts/fplrp/fplrp448.pdf


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