# Wall Removal and Hidden Beam in Attic



## derbow

I have a wall that I need to take out that is just under 17 ft. long. It goes down the center of the home on the second level. It seems as if it should be a load bearing wall, but there are 2 separate cased openings 48in. wide along that wall that do not have headers in them. It makes me wonder whether it is load bearing after all. Anyway, I want to put a hidden beam in the attic, but an engineering friend of mine recommended building a truss in the attic instead. Here is a little more info:

The roof system is stick built, so there are no manufactured / engineered trusses.The ceiling joists are on 16 in. centers as well as the rafters. There are purlin braces every 48 in. on center. The braces go to the top of the wall in question, and the ceiling joists (that are also serving as rafter ties) are nailed together over this wall. Here is a picture of the existing roof framing over the area that I am talking about:










My engineering friend suggested building a "truss" that extended over the 18 ft. span and rested on support beams on either side. The ceiling joists would be attached to this "truss" with either hurricane straps or other 2x4 blocking of some kind. Here is a picture of the type of thing he is suggesting. It's kind of like a strongback of sorts, I think:










Have any of you built anything like this before? The concept makes sense to me. He even mentioned tying the peak of the "truss" to the existing ridge beam. He thinks that would strengthen things even more. I don't think that I can get a 16 in. tall LVL into the attic to use as a normal hidden beam. With this "truss" approach, I think I could use two 2x12x20's as the bottom of the truss. It's going to be a good trick to get those in the attic also, but I think it is possible.

Any thoughts or suggestions here would be greatly appreciated. Thanks!


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## MarkJames

It's load-bearing.


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## derbow

MarkJames,

I am assuming that it is load bearing. That's why I'm trying to figure out the best way to install hidden support in the attic that can span the 18 ft. necessary. Getting a LVL in there would be nearly impossible without removing a lot of other existing framing and making the cost and time a whole lot more.


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## MarkJames

derbow said:


> MarkJames,
> 
> I am assuming that it is load bearing. That's why I'm trying to figure out the best way to install hidden support in the attic that can span the 18 ft. necessary. Getting a LVL in there would be nearly impossible without removing a lot of other existing framing and making the cost and time a whole lot more.


This is out of my league, but sure looks expensive from here.


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## Peter_C

What about removing a gable vent and bringing the LVL in that way? Or just cut a hole in the siding!


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## jlhaslip

I have done this (or similar) in the past.
Cut out enough ceiling to pass the material into the attic space. The drywall can be patched later.
Support each side with a temporary false wall.
Install the beam. Add hangers to attach the ceiling joists to the new load bearing beam.
Remove temp walls. Cash cheque.


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## ScipioAfricanus

derbow said:


> I have a wall that I need to take out that is just under 17 ft. long. It goes down the center of the home on the second level. It seems as if it should be a load bearing wall, but there are 2 separate cased openings 48in. wide along that wall that do not have headers in them. It makes me wonder whether it is load bearing after all. Anyway, I want to put a hidden beam in the attic, but an engineering friend of mine recommended building a truss in the attic instead. Here is a little more info:
> 
> The roof system is stick built, so there are no manufactured / engineered trusses.The ceiling joists are on 16 in. centers as well as the rafters. There are purlin braces every 48 in. on center. The braces go to the top of the wall in question, and the ceiling joists (that are also serving as rafter ties) are nailed together over this wall. Here is a picture of the existing roof framing over the area that I am talking about:
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> My engineering friend suggested building a "truss" that extended over the 18 ft. span and rested on support beams on either side. The ceiling joists would be attached to this "truss" with either hurricane straps or other 2x4 blocking of some kind. Here is a picture of the type of thing he is suggesting. It's kind of like a strongback of sorts, I think:
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> Have any of you built anything like this before? The concept makes sense to me. He even mentioned tying the peak of the "truss" to the existing ridge beam. He thinks that would strengthen things even more. I don't think that I can get a 16 in. tall LVL into the attic to use as a normal hidden beam. With this "truss" approach, I think I could use two 2x12x20's as the bottom of the truss. It's going to be a good trick to get those in the attic also, but I think it is possible.
> 
> Any thoughts or suggestions here would be greatly appreciated. Thanks!




You are describing a "girder truss".

Such a thing needs to be designed by someone that knows what they are doing and has the proper software to do this to take into account all the various loads that would be in effect. Loads like wind loads, seismic loads, gravity loads and lateral loads. Plus design the components for attaching loads to the sides of the bottom "chord".

It can be done but is not easy.

Andy.


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## jlhaslip

ScipioAfricanus said:


> You are describing a "girder truss".
> 
> Such a thing needs to be designed by someone that knows what they are doing and has the proper software to do this to take into account all the various loads that would be in effect. Loads like wind loads, seismic loads, gravity loads and lateral loads. Plus design the components for attaching loads to the sides of the bottom "chord".
> 
> It can be done but is not easy.
> 
> Andy.


Agreed.


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## Windwash

I would skip the built in place truss and just do the 16" LVls. You are going to have to patch sheetrock no matter what you do as you are removing a wall below the beam so push insulation to the side and cut back the ceiling as needed. If there is strapping/hangers that go under the ceiling joists you will want the new sheetrock joints to be at least 12-16" away.

On a 4/12 pitch like it looks like you have, the 18'x16" LVL laid flat will slide up in between the 16" OC ceiling joists while someone in the attic flexes it down while it is pushed up. 

You will not have to build temp walls if the beam is on top of the ceiling joists as removing the existing wall will be done after the beam and hangers are in place.


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## jlhaslip

Windwash said:


> You will not have to build temp walls if the beam is on top of the ceiling joists as removing the existing wall will be done after the beam and hangers are in place.


May not be able to properly attach the ceiling joists to the beam until the wall is removed. Maybe. Maybe not.


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## m1911

I've been considering carpeting downstairs bedroom before Aunt Mary comes to visit in a couple of months we haven't decided on a color or what type


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## royhill62

I did almost the exact same thing- 18' lol it sat on jack studs that beaded on top of existing walls , then I supported the existing ceiling joists with short studs that were attached to the lvl... it worked great!

Sent from my SAMSUNG-SM-G920A using Tapatalk


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## derbow

Thanks for the responses so far. My main concern is not "how" to do it, it is whether or not what I am planning to do will actually work. Are two 2x12x20 yellow pine enough to carry the weight by themselves, or do I need the extra support that a girder truss like I have described would provide. I would rather over build than under build. 

Another issue here is both a time deadline and cost. All the materials for the girder truss together costs less than one LVL. Patching the drywall is a given. The attic space is already tight, so most of the work will be done from underneath after the lumber gets placed in the attic.


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## ScipioAfricanus

derbow said:


> Thanks for the responses so far. My main concern is not "how" to do it, it is whether or not what I am planning to do will actually work. Are two 2x12x20 yellow pine enough to carry the weight by themselves, or do I need the extra support that a girder truss like I have described would provide. I would rather over build than under build.
> 
> Another issue here is both a time deadline and cost. All the materials for the girder truss together costs less than one LVL. Patching the drywall is a given. The attic space is already tight, so most of the work will be done from underneath after the lumber gets placed in the attic.


Wow man, you really are not getting it.

I am done with this.

Andy.


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## Calidecks

derbow said:


> Thanks for the responses so far. My main concern is not "how" to do it, it is whether or not what I am planning to do will actually work. Are two 2x12x20 yellow pine enough to carry the weight by themselves, or do I need the extra support that a girder truss like I have described would provide. I would rather over build than under build.
> 
> Another issue here is both a time deadline and cost. All the materials for the girder truss together costs less than one LVL. Patching the drywall is a given. The attic space is already tight, so most of the work will be done from underneath after the lumber gets placed in the attic.


You must first tell us what the wieght is and what forces there will be. :laughing:


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## Metro M & L

Sometimes you just don't know you don't know.


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## RickMacKay

A guy could run an 18' LVL or equivalent through one end of the gable or hip and hang the ceiling joists from it. Undoubtedly more than a few purlin braces would have to be re-arranged. Also, each end of the beam would have to rest on established bearing, i.e. possibly posts sitting directly on the foundation or new footings in the basement. It is a bearing wall, but the braces almost act like trusses in a half-axxed way, that may explain why you are not seeing headers above the 48" openings. So that would be a good strategy to approach your project. However, you must bring a structural engineer into the discussion and have him design a system that will ensure you are not liable for any problems down the road. Even if there is a small crack on a different wall from, say, water intrusion, the homeowners are likely to point the finger at you. Your defense is that you did it "by the book." Also, you don't say where the project is. There are all kinds of loads to calculate, snow loads being one of them. Roofs in the south are engineered to be flimsier than roofs up north. Good luck.


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## Warren

Sky hook. I think you kust need to carry the ceiling and the kickers. The 18 inch lvl seems excessive to me, but I am not there, nor am I an engineer


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## mako1

First off what these guys are trying to tell you is"your in over your head". You have mentioned twice that you have been talking to "your friend " the engineer.Why not let him figure it out? You will need stamped drawing to get a permit for this anyhow.
You are getting a permit aren't you? One last piece of advice form me.Make sure your insurance is paid up.


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## hdavis

There are no prescriptive truss designs. This will have to be engineered. Also, regarding whether a couple 2X12s could be used as a beam for an 18' span - no.

It's pretty clear you have no idea how long it would take to build this yet-to-be-engineered truss in place in an attic. I'll give you the answer - way too long. Same answer for a box beam.

Go to your yard and see if they'll size an LVL for you for free, and get a good set of plans.

This is structural engineering, not really general handyman stuff.

PS, I don't believe you have a structural engineer buddy, or he wouldn't have gone down that path. LVL is going to be cheaper and faster overall, unless your time is free.


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