Add 2nd story to pole barn...

[geminimoon66]

In Ohio I am planning on building a standard 24' X 26' pole barn with 12' ceiling, I want to add a 2nd story apartment to this. The apartment will have standard 2x4 stud wall 16" on center and a 4/12 pitch roof.

If I use treated 6" X 6" X 16' posts spaced 6 foot on center (in stead of 8'), will this support the second floor apartment without any issues?

This is a cash project I am building on my own and our local lumber yard doesn't seem to have an answer to this so any input would be much appreciated!


Thank you very much for any input!

[alex trent]

I do not think the 6x6 posts are your primary problem.  If I understand this, you will build the apartment at the 12 foot height where the roofline meets the outside wall?

If that is the case, then.

How will you support the "apartment" floor joists.  1) Need beams along the outside able to support the joists and the roof...they will have to be hefty. 2) Also you have 24 foot span for joists so will need support in the middle as unlikely you can reasonably span 24 feet without special construction. 3) on what does the plate for the 2x4 wall rest?

Maybe a simple drawing would help...i may be misunderstanding it all.

Do you have local codes?  I think this may be outside the parameters wherein you can do this ...easily.

[geminimoon66]

The 6x6 will be notched on each side with a 2x8 nailed on and the floor joists will sit on the top of these at 12' off the ground.   Was planning on nailing a 2x4 on top of joists to act as a sill plate for the 2x4 walls.

Not much for drawing but hopefully you can understand what I mean...

Well, then again, I can't seem to be able to add the picture I made...

[Don_P]

The wall height gives a bit of heartburn.
The top of the post frame will need girders just like any pier and beam, the continuous wall height post is braced by the wall sheathing. It'll take more than a 2x8 to act as the girder, but that can be sized.
The design of a post frame building is a specialty.
This is a good bookmark;
http://www.postframeadvantage.com/pub/Diaphragms
and especially this document from that link;
http://www.postframeadvantage.com/elements/uploads/fckeditor/file/Wind-Governed%20Design%20Example.pdf

Edit...
To post pics you'll need an online photohost like photobucket, etc. Post a link to the picture between a set of {img} tags in your post.

[hpinson]

Be cautious. This is the pole barn that came with my land.  A week of heavy snowfall a few years back snapped the 6"x6" poles and 2"x8" truss roof like twigs.  I think the construction framework was too sparse. Roof spans were too long and the trusses could not support the snow load. Nails pulled out like they were nothing! It is a good lesson to have firsthand experience with.



I don't mean to be discouraging.  I'm sure there is a way to do it properly, and there is quite a bit of literature on the subject if you do some research.  Hopefully you can take some time and know what's safe before diving in.

A drawing would really help!  Here's a post on how to add images: http://countryplans.com/smf/index.php?topic=11663.0   Google Picasa is a great way to share images, and directions on doing that are towards the bottom of that post.

[geminimoon66]

First, thanks for the info on how to upload a photo.



This drawing is how I was planning on adding the second floor to the top of the 6"x6".  Hopefully someone will be able to understand what I have drawn!  lol
The 2nd story walls will all be 2"x4"s 16" on center and the roof will be 2"x8"s 16" on center as well.  The ceiling of the ground floor will be insulated and I will put a 5/8" drywall on followed by 1/2" drywall on that as a firewall (ceiling).

The 6"x6" posts will be 4' in the ground sitting on 4" concrete pads.  I intend to nail treated wood blocks on the end of the posts before I bury and pack them in gravel.

I will look at the links some of you have provided and hopefully can get a little more info on doing this.

[Don_P]

The notched joists pop out immediately, those would split. Set the entire joist on top of the girder.
Footings need to be at least 8" thick although they should not extend more than 1/2 their thickness beyond the post, they may need to be larger depending on soil bearing strength and load.

[alex trent]

Where does the roof attach to this? Rafters or trusses rest on what?

[hpinson]

That seems more of a timberframe or post and beam approach than pole barn.

There is a lot of good information out there about timberframeing, and joinary techniques are well estblished, both tradtional and modern -- a first stop might be your local library to see what they have on this topic.  Amazon.com too. Some decent references are:

Timber Frame Construction: All About Post and Beam Building
http://www.amazon.com/Timber-Frame-Construction-About-Building/dp/0882663658

Timber Framing for the Rest of Us: A Guide to Contemporary Post and Beam Construction
http://www.amazon.com/Timber-Framing-Rest-Contemporary-Construction/dp/0865715084/ref=sr_1_1?s=books&ie=UTF8&qid=1343826747&sr=1-1&keywords=post+and+beam

Building the Timber Frame House: The Revival of a Forgotten Art
http://www.amazon.com/Building-Timber-Frame-House-Forgotten/dp/0684172860/ref=pd_bxgy_b_img_b

A Timber Framer's Workshop: Joinery, Design & Construction of Traditional Timber Frames
http://www.amazon.com/Timber-Framers-Workshop-Construction-Traditional/dp/188926900X/ref=pd_bxgy_b_img_c

The Craft of Modular Post & Beam: Building log and timber homes affordably
http://www.amazon.com/Craft-Modular-Post-Beam-affordably/dp/0881791318/ref=sr_1_3?s=books&ie=UTF8&qid=1343826747&sr=1-3&keywords=post+and+beam

Build a Classic Timber-Framed House: Planning & Design/Traditional Materials/Affordable Methods
http://www.amazon.com/Build-Classic-Timber-Framed-House-Traditional/dp/0882668412/ref=sr_1_9?s=books&ie=UTF8&qid=1343826747&sr=1-9&keywords=post+and+beam

Search this forum on the topic of "timberframe" or "post and beam"  I believe there are quite are few here who have taken this approach in their builds.

There are several other online forums dedicated to the topic:

Timber Framers Guild
http://forums.tfguild.net/ubbthreads.php

Forestry Forum - Timber Framing/Log construction
http://www.forestryforum.com/board/index.php/board,11.0.html

[Squirl]

From many past member comments my understanding is Ohio does have a building code.  I don't know the exact one, but since the IRC relies on AWC guidelines, it should suffice for basic span/sizing charts.

Almost no common lumber can span 24 ft unsupported.  So the 2nd floor will need some type of span support most people put in the center.

In stick framing, when spanning lumber across large spaces to distribute the weight of floors and roofs for openings, there is used a header/girder.  That is what you are trying to do with your 2x8s. (distribute the weight from the roof and the floor to the 6x6 posts).
Here is a post with a link to the tables, and a description of how to read them.
http://countryplans.com/smf/index.php?topic=10511.0
2- 2x8s are a little undersized for a girder with the weight of a roof and center bearing floor in a 24 ft wide building.

In stick framing a 2x6 is allowed to be spaced 24" O/C.  (http://publicecodes.cyberregs.com/icod/irc/2009/icod_irc_2009_6_sec002_par005.htm)
I could see a reasonable argument that a 6x6 can be spaced 6ft O/C in that it is the size of 3-2x6s and should handle the compressive forces.  The problems come in with the other forces.  The building code also usually limits story height to 10 ft without lateral support.