# 36' LVL Ceiling Beam - Is it possible?



## aar0nhurst (May 13, 2020)

Home built in 1961. Rafter, hip roof. Looking to add a flush beam to span 36'.

Can someone help me better understand roof load and what type of LVL beam I would need to span 36'? I know I can do the work and I am confident in my job execution, but I don't know how to calculate what type of beam I need. I assumed that a few 2"x10"x36' LVLs sistered together, posts at opposite ends, concrete footers, and joist hangers would do the trick. But I'm stuck on engineering the beam!

*My question:*
How do I figure out what type of LVL beam can be used?


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## griz (Nov 26, 2009)

You need to hire an engineer...


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## aar0nhurst (May 13, 2020)

griz said:


> You need to hire an engineer...


Definitely will


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## Seven-Delta-FortyOne (Mar 5, 2011)

Not something builders size on their own.

Project like this is probably going to need to be permitted anyway, and the building dept is most likely gonna need to see the engineering.

_Might_ be able to have the lumber size it for you, since it's going to be through a company like Boise Cascade or Weyerhouser. They do a lot of their own engineering.

However, the building dept might not accept that. They might want a site specific engineering report, talking local wind and seismic into consideration.


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## Fouthgeneration (Jan 7, 2014)

Build a truss..... a 4-6' deep truss, especially if steel rods/ cables are used for tension members. You might have to push it above the roof line, and weatherproof the exposed portion, think suspension bridge.....Or hide the structure in a 'clerestory' which would allow natural light and no loss of head room.

Run cables under plywood deck between opposite rafter tails to reduce dead & live loads on ridge beam


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## greg24k (May 19, 2007)

If you want to span a beam 36' what is the beams carry span? 
Also, are you trying to make living space up there or only for walk-up storage?


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## hdavis (Feb 14, 2012)

You have more than the beam to worry about, you have to get that load down to correctly sized footers.


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## greg24k (May 19, 2007)

hdavis said:


> You have more than the beam to worry about, you have to get that load down to correctly sized footers.


Most definitely he will have cut the wall bellow and install a post to carry point load continuously down to the foundation and in some cases being this a gable wall most likely the main house girder is resting on that wall and if there is no structural pier and the girder just cut into a block, in many cases the block would have to be cut and solid grouted down to the footing (depending on how old the house is and how many stories the house is)


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## aar0nhurst (May 13, 2020)

Fouthgeneration said:


> You might have to push it above the roof line, and weatherproof the exposed portion, think suspension bridge.....Or hide the structure in a 'clerestory'


 Uhhh........I'm hoping this is sarcasm, lol.


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## aar0nhurst (May 13, 2020)

greg24k said:


> ...what is the beams carry span?


I was hoping someone on here could help me answer that.



greg24k said:


> Also, are you trying to make living space up there or only for walk-up storage?


Neither. I'm trying to open up the floor plan between the kitchen, living area, and dining room. Attic space won't be used.


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## Seven-Delta-FortyOne (Mar 5, 2011)

aar0nhurst said:


> I was hoping someone on here could help me answer that.


Not here.

That's where engineers come in. I never size those things.

I sketch out a floor plan, rafter size/spacing, dimensions, foundation details that I can ascertain, and take that info to my engineer. 

And voila, like magic, he spits out an answer.  :thumbsup: :laughing:


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## aar0nhurst (May 13, 2020)

greg24k said:


> Most definitely he will have cut the wall bellow and install a post to carry point load continuously down to the foundation and in some cases being this a gable wall most likely the main house girder is resting on that wall and if there is no structural pier and the girder just cut into a block, in many cases the block would have to be cut and solid grouted down to the footing (depending on how old the house is and how many stories the house is)


Man, yes. So I have a CMU block wall as the girder and I assume it's on top of a concrete footer (I haven't seen the footer). If I understand you correctly, it's possible that I would need a solid pier down to the footing cut through my block girder? And only then could I set the post for the beam?

FYI, I know there is fungus on the floor joists. I am getting them treated and a vapor barrier put in place. Luckily no rot or termite damage.


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## greg24k (May 19, 2007)

The beam carry load is the with of the house perpendicular to the girder (the joist span on each side of the girder)

That said I'm not giving you structural advice here I'm just curious to know what size that beam would need to be.

As the foundation and the footing goes that is a different story and the integrity of it and if it can support the additional load, i.e that would depend on the footing width, depth, and the soil.

So as an example with basic calculation...If you plan on doing a habitable attic space to meet L/360 floor load criteria @30LB PFT design load...and if your building width is 24' you need a beam to support a total of 13,320LB load that 370LB per foot... so every bearing point on each side has to support an additional 6,660LB. 

That said a 5 1/4" x 18" beam can support 391LB PFT which is only good for a 26' span and the weight of that beam is 578.8 LB so I don't know how you plan on getting that beam inside, because the beam to span 36' will be even more and a much larger beam.

You should consult with an engineer and see what would be a steel I-Beam option.

Good luck


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## hdavis (Feb 14, 2012)

Keep in mind, for replacing a ridge board with a structural ridge on a hopped roof, you'll most likely have columns coming down through living space, not the exterior walls. There probably won't be foundation under them as it was built.


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## Seven-Delta-FortyOne (Mar 5, 2011)

Take this for what it's worth, and you're getting it for free, so it's probably worth exactly what you're paying for it. :blink:


You're a bit over your head on this one. We can't give you all the info you'll need to do this job. It's a serious structural remodel, and it takes a lot of experience to pull these off correctly and safely.

In fact, the Mod staff here usually shut these down right away. They must be feeling generous.  :laughing:

The questions you are asking are actually irrelevant if you were getting this job permitted, because the AHJ would require you to do what we've repeatedly told yo to do, which is "Go get it engineered". 

I'm guessing you're going to skip the permit process on this one. :blink:

If you are in fact in the construction trade, this is too big of a project to tackle for a laborer. Why don't you have a co-worker or 2 over on a Saturday, put a 12 pack on ice, and see if they can give you some help.


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## hdavis (Feb 14, 2012)

Personally I do as much structural calcs as possible before going to a SE just so I have an understanding of what the options are. Nothing worse than a structural design you don't want to build.


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## rrk (Apr 22, 2012)

hdavis said:


> Keep in mind, for replacing a ridge board with a structural ridge on a hopped roof, you'll most likely have columns coming down through living space, not the exterior walls. There probably won't be foundation under them as it was built.


I dont think he wants to replace ridge, just carry ceiling load to be able to remove interior walls

the one I did recently was 21 ft long 5 1/2 x 16 microlam, which means nothing in his case but may give him an idea of size


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## aar0nhurst (May 13, 2020)

greg24k said:


> You should consult with an engineer and see what would be a steel I-Beam option.


I'll call the lumber yard tomorrow and get an engineer's information.



greg24k said:


> Good luck


Thank you, sounds like I'm going to need it!


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## aar0nhurst (May 13, 2020)

Seven-Delta-FortyOne said:


> In fact, the Mod staff here usually shut these down right away. They must be feeling generous.  :laughing:


D'oh! Didn't realize that.



Seven-Delta-FortyOne said:


> The questions you are asking are actually irrelevant if you were getting this job permitted, because the AHJ would require you to do what we've repeatedly told yo to do, which is "Go get it engineered".


I'm going to call an SE on this one for sure. I wasn't planning on getting this permitted but after reading everyone's comments, I'd be a fool not to listen. And as far as "irrelevant questions" go... you're not wrong but a day ago I didn't know so much went into a beam! I figure better for me to ask and listen than to not ask and end up with a collapsed house.


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## aar0nhurst (May 13, 2020)

Can't thank everyone enough for the help, info, and guidance on this one. I'm going to call my lumber yard tomorrow and get a couple SE numbers. I'll post an update once I have more info on my project.


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## Warren (Feb 19, 2005)

The place where I get my steel will usually do the calcs for the beam. Don't bother with the lumber yard. A beam that length, without intermediate support is gonna be steel.


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## greg24k (May 19, 2007)

Warren said:


> The place where I get my steel will usually do the calcs for the beam. Don't bother with the lumber yard. A beam that length, without intermediate support is gonna be steel.


Around here the steel shop will not make you a beam unless you have an engineer's or architects stamped plan.
I designed a beam a while back did all the calculations and did my own drawings and engineer on staff in the metal shop checked and said its the right calculations the beam will work, but in order to make and release that beam, I have to bring a stamped drawing.


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## Dirtywhiteboy (Oct 15, 2010)

Well he is in Kentucky,,, I heard they don't do a lot of permits there:blink::blink:


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## greg24k (May 19, 2007)

Dirtywhiteboy said:


> Well he is in Kentucky,,, I heard they don't do a lot of permits there:blink::blink:


Sounds like a little town in NJ, I did a kitchen remodeling, construction was going on all over the place and it seems I'm the only one who wanted to get a permit :laughing:
Took me almost a week to catch someone in the office and the lady actually blew the dust off the permit jacket before she handed it to me.:thumbsup:


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## aar0nhurst (May 13, 2020)

Dirtywhiteboy said:


> Well he is in Kentucky,,, I heard they don't do a lot of permits there:blink::blink:


I have absolutely no idea what you're talking about...:vs_worry: :no: :shifty: :laughing:


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## hdavis (Feb 14, 2012)

aar0nhurst said:


> I have absolutely no idea what you're talking about...:vs_worry: :no: :shifty: :laughing:


A permit is something your AHJ may give you in exchange for money. It lets you build and get inspected at various stages of the build.:thumbsup:


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## aar0nhurst (May 13, 2020)

So get this, I called the few (4) steel places in my area and none provide residential steel work nor could offer an engineer to help me. I called the largest steel company and told the lady answering phones, "I know you don't do residential but at least let me talk to one of your guys and hopefully they can refer me to someone." Guess what...nothing. Well, she did give me a number to a company 2 hours away but that won't work. (not that desperate yet) :no:

I called "the" lumber yard (1) and had to leave a message for the manager because no one in the office knew how to engineer a beam, wood or steel. He's yet to call me back. 

Then I was like, duh, just call the county. The guy was nice but couldn't help me out. Acted like he'd never seen a residential plan that included a steel beam. When I asked him about submitting my own plans, he literally told me that he doesn't need an engineer's approval on plans. He just reviews them and unless they have incorrect codes, approves them.  SMH 

I'll keep trying next week but I thought I'd share my fun filled day. Updates to come when I have them.


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## griz (Nov 26, 2009)

your lack of understanding what is involved in engineering this beam is getting in your way.

with what you have involved no lumber yard or steel company will want to deal with you.

you need a stamped plan from an acceptable engineer to proceed.

as many have stated there is *WAY* more going on than a simple span detail.

steel fabricators want stamped engineers drawings before they will talk to you...

otherwise they just figure you are a dumb azz home owner/diyer that don't know your azz from a hole in the ground...

you will* NOT* get any magic internet answers...
until you get this and go to an engineer you will not progress in your project...


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## Dirtywhiteboy (Oct 15, 2010)

It's Kentucky :blink: They just eye ball and wing it ober dar.


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## aar0nhurst (May 13, 2020)

griz said:


> your lack of understanding what is involved in engineering this beam is getting in your way.


So you're saying I should stay ignorant? I'll ask until I'm satisfied. Or until people stop answering. Knowledge isn't the key, understanding is.



griz said:


> you will* NOT* get any magic internet answers...
> until you get this and go to an engineer you will not progress in your project...


What exactly do you think I am trying to do? I asked for advice here, and the advice was to get an engineer. I've said repeatedly that I'm getting an engineer. I'll say it again. I'm getting an engineer. Apparently, in BFK(entucky) no one engineers anything except moonshine.

I have:
4:12 pitch roof
Stick Frame (rafters)
15psf roof live load (snow) - per 2018 Kentucky Building Code
10psf roof dead load 
20psf ceiling live load 
10psf ceiling dead 
27' House width (eave to eave)
12.5' to middle wall

Roof live load (snow): 15psf x 13.5 = 202.5
Roof dead load: 10psf x 13.5 = 135
Ceiling live load: 20psf x 6.25 = 125
Ceiling dead load: 10psf x 6.25 = 62.5
Total load = 525 pounds per lineal foot

Now tell me what engineer would turn me away with that information in hand?

I truly am grateful for everyone who's offered advice because you don't owe me your time. But *griz*...you can worry bout your own self.


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## aar0nhurst (May 13, 2020)

hdavis said:


> A permit is something your AHJ may give you in exchange for money. It lets you build and get inspected at various stages of the build.:thumbsup:


Ohhhh, I think I heard about those things when I went to the big city one time. :laughing:


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## ScipioAfricanus (Sep 13, 2008)

What wind and seismic category are you in?

This kind of engineering is not difficult, getting a PE or SE license is really GD hard though.

Andy.


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## Rio (Oct 13, 2009)

aar0nhurst said:


> So you're saying I should stay ignorant? I'll ask until I'm satisfied. Or until people stop answering. Knowledge isn't the key, understanding is.
> 
> 
> 
> ...


Well then, get on the phone or on the net and locate one, get a price and go from there. They'll likely want a set of plans with a couple of sections. Once you have the stamped plans then go find a fabricator, depending on where you are in the country they might have to be certified for any welding done. 

Like Warren said it's going to be steel at that span so in addition to the beam you want to have the engineer call out how you're going to transition from the beam to the columns and on down to the footings, have them provide the details and pertinent information.


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## greg24k (May 19, 2007)

aar0nhurst said:


> So you're saying I should stay ignorant? I'll ask until I'm satisfied. Or until people stop answering. Knowledge isn't the key, understanding is.
> 
> 
> 
> ...


You missing a beam load.:blink:

That said, there is a rule of thumb when you calculate the steel I-beam size... you take the total span in inches divide that by 20 so in your case 36x12/20= 21.6".... Now the depth of the beam is usually 1/3 to 1/2 of that so lets take the lower number 21.6 X .33= 7.128 so you will need a 
22x7.5 I-Beam the weight of that beam will be in the neighborhood of 75-80 LB per foot 36 X 80=2,880 LB beam. Good luck with that one.


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## rjconstructs (Apr 26, 2009)

Stamped engineering using steel is the only way I would touch this.


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## Rio (Oct 13, 2009)

Thought I'd mention to the poster that in addition to structural engineers civil engineers can usually do calcs for structures, at least that's the case out here.


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## Seven-Delta-FortyOne (Mar 5, 2011)

aar0nhurst said:


> So you're saying I should stay ignorant? I'll ask until I'm satisfied. Or until people stop answering. Knowledge isn't the key, understanding is.


No. He stated very clearly that calling steel fab companies before you have engineering is ass-backwards, and that's why you haven't had any success.





aar0nhurst said:


> I truly am grateful for everyone who's offered advice because you don't owe me your time. But *griz*...you can worry bout your own self.



Telling someone who is taking their own personal time, and decades of experience, to help you to understand something that is obviously over your head, to mind their own business, is incredibly ungrateful.

I guess this why most of these threads get shut down right out of the gate. Apparently, the average HO is too proud to be educated. :blink:


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## Windwash (Dec 23, 2007)

If your opening up the whole 25x36 and taking down all interior walls this is basically a full gut. New electric, Hvac, flooring, etc. If that's the case, another option would be to just tear the whole roof off and redo it with 25' trusses. New ceiling could be flat, vaulted, storage or room in attic. could even change from hip to gable ends if you want. Truss company would engineer and there would be no new point loads, footings or machine rental.


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## HAPConst. (Mar 14, 2019)

Engineer will spec it out and lumber yard can put it together and deliver to the site. Make sure to get the permit and have it inspected to cover your bottom. 36’ is long and the beam alone will be a heavy sucker. You will need a crane and lots of strong people.


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## db4924 (Nov 24, 2015)

your probably looking at something more along the lines of 24inch tall triple microlam beam, or greater possibly a flitch beam (i.e. lvl/steel/lvl/steel/lvl) in that general dimension approved by engineer.


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