Removing barn loft reinforcing

[mtaves]

I have a 30'x50' barn with a 30' high loft I have finally cleared of pigeons and all their leavings. I want to turn it into a usable space, but bracing inside really limits the practical floor space. The end wall bracing I will leave, but there is a brace mid-way on the roof down to the floor that I need to remove. I have seen numerous barns in my area that have collapsed, where the building had this same profile (although they were much longer) so want to make sure I don't screw up a loft that is currently in pretty decent shape. I have included two pictures to give a sense of the geometry/size. You can see the brace is bowing a little, which tells me there has been some (but not much) sagging in the middle already. I would appreciate any feedback/ideas on what to do as an alternate bracing to allow me to safely remove this brace. I have 2 ideas so far:

1: add cross cabling 10-12' off the floor
2: add diagonal bracing between studs, the opposite way of existing bracing. The existing diagonal bracing does not give any additional support at the midpoint of the roof. Bracing high at the mid-roof point and going down towards the ends, in an inverted-V, should improve rigidity over what the current 10' long 2x4's are accomplishing.

Thanks in advance for your comments.

 

[hslogger]

Oh man what a structure. I dunno Why you figure these are a PIA for you but I want to point out one thing I do know. These barns were built to hold loose hay and so when full, they were full of loose hay and not hay bales. They were not designed for the weight and distribution of weight modern people demand in their storage desires. That in part has been one contributing factor IMHO to the demise of these structures. I will be glad to see and hear some one here who has engineering background as to pounds per square inch and external framing.

 

[Egon]

The two by fours shown probably do little to nothing in structural support.

If you can find the original design plans they should answere your questions.

Just offhand there could be more lateral bracing between the beams.

 

[mtaves]

Thanks for the quick replies!

hslogger: I realize now I didn't say what I would be using the space for. Storing hay bales is a perfectly reasonable assumption considering it is a barn loft, but I am actually planning on using it as a martial arts and dog training space for winter months when outdoor temps are not conducive to this kind of activity. Adding livestock to my acreage is in the long term plans, and have other structures with some bale storage capacity and am hoping to keep this space clear if at all possible. Floor loads should definitely stay within whatever the original design intent was.

Egon: totally agree that additional lateral bracing would really help. The way the bracing is set up, it looks like the plan was to resist bulging outward from any pressure of the loose, piled hay, rather than to resist buckling. Even if those 2x4's do almost nothing (which seems obvious now that you pointed it out), still would like to make sure this structure doesn't go the same way as neighboring barns have.

 

[BKBoiss]

Not sure if this helps you much because I was really young (7-8) but we had a large hip roof that my dad converted into a storage work shop and still kept an area for hay storage. One third was left as is for hay storage, the other two thirds he built a floor about 12 or 14 feet up I would say then another floor about 6 feet above that. That small 6 foot space we stored lumber furniture and all sorts of random junk. The top floor still left tons of room up to the ceiling and we had a little bit of a workshop and more storage up there. He ran I think two beams down the center of each floor and lined them up with the main support beams down stairs in the main part of the barn. He replaced some beam sections and most of the posts to handle the extra load and well as straiten out the barn from years of sagging. In the 6 foot crawl space he ran cable with pullers right up against the bottom of the top floor. I think it was two or three across from side to side and two diagonal from corner to corner. Like I said I was really young and this barn seemed to be hundreds of feet tall to me but maybe this will give you some ideas. All said and done the barn had four floors. The main one on ground level with the stalls the main original loft then the two new ones on top of that.

 

[Sodo]

HS I don't belive you really have a question you just wanted to post pics of your wicked loft. Of which I am insanely jealous,,,,,:thumbsup:

If those little braces are obviously holding up some sag, whats the problem with leaving them? Why not just build a closet storage on them, you can even make it a little stronger with the shear strength of plywood.

 

[Budweiser John]

First off, I AM NOT a structural engineer but from a practical point of view two 2x4s in the center of a 50' long building don't offer much in the way of structural support.
If there is a sag in the ridge line and the side walls of the building are still plumb that would indicate the " bow string" rafters are bending.
Digging back through my career as a carpenter, I recall a project involving a 100 year old church with a similar issue. Strong backs were added to the mid points of the rafter run and tie rods with turnbuckles were placed at the 1/4 points along the length of the building and running from side to side.
Save that beautiful structure.....
B John

 

[mtaves]

Sodo: I have to admit you are partially correct. It took too long to figure out how to keep pigeons out, then had to shovel out their manure which was 1ft thick in some places. Glad to finally be able to walk around up here.

To your question though: between the brace on one side, and the silly furnace room on the other side (whole other topic), the 30ft width is reduced to somewhere between 15-20ft across at this point. The martial art I practice uses longswords, spears, and staves ranging in length from 3ft to 6ft. With their reach you need to be able to get in/out of the other guys range without worrying about getting the training tool caught in a 2x4, or backing into it. It can definitely be done by restricting the sparring area to one loft end or another, but is way more fun with full access to a larger area.

 

[mtaves]

BKBois: that does help give me some other ideas of what I can do with all the extra ceiling height. Thanks for the tips!

Budweiser John: Thank you very much for the insights. I love this structure which is still remarkably intact. This is the perfect time to make sure it stays that way - before significant sag starts to set in.

 

[Jim Timber]

I'd love to see the bottom of that floor, if you'd be so kind.