“Hung” Barn

[Prizl tha Chizl]

 

 

 

 When we moved out to Clyde (just across the river from Lone rock,) a neighbor told us they called this type of barn a "hung" barn. The bents on the second floor are built like a suspension bridge, so there are no posts to contend with on the dairy floor. We've collected stories from other folks in the area and have now seen several barns in the neighborhood that are built this way, but have never seen one outside of our community out in any of the barn books I've looked at. We understand there was one builder in the area who was responsible for all of the hung barns in Clyde, and the family that lived on our land first spent a year building the foundation, then he had to go to the "Great War," and raised the barn when he came back.

Has anyone else seen barns built this way, or have any other information about this design?

Our barn, (and the entire farm) was in extreme disrepair when we moved here. We've spent the last 13 years on a shoestring budget back-to-thelanding it, and repairing/ rebuilding what we can when we can.

I put a new roof on the south side, (solo!) and have replaced most of the floor deck and some joists. I'd like to build a woodshop/art studio in the loft and use the dairy floor for a beamery, but have some (many) repair questions. I'll try and post them as comments to this thread with photos so folks can see what I'm getting at.

Thanks for the cool site, I've lurked around here for years, but just joined!

[doc henderson]

I will be of no help to you, but let me be the first to say, welcome, and love the design.

[beenthere]

Prizl
Welcome to the Forestry Forum

You speak of a barn design in "your area",  is it in WI?

That barn design is one I grew up around in Iowa, and have also seen in Wisconsin. Imagine it was a good design depending on available materials (nuts and bolts) and travelled across the country or around the world. Don't know other than central mid-west USA.

[Prizl tha Chizl]

Yeah, Clyde township, (no town any more,) is in southwest Wisconsin roughly in the center of a triangle formed by Lone Rock, Dodgeville, and Highland. 

[Don P]

A queenpost truss rather than a suspension bridge.

The lower beam here could not support me. The load is carried by the arch. The verticals are hanging from the arch and support the lower cord. In tension, steel shines. He replaced my wooden hangers with steel rods.

[Prizl tha Chizl]

 These two rotten tenons are in the bents next to the hay loft door. The bottoms of the rafters had all been sistered on by a previous wood butcher. The beam they rest on needs to be replaced, as well as the floor joists immediately below, but I think this is my most pressing issue.
So this one is on its way.

 
This is one that I "repaired" 6 years ago. I used a come along and chains wrapped around that steel rod to pull the tenon back into its mortise, (a good 5 or 6 inches.) with about an inch left to go, the top of the post began to split where it was joined to the beam above it, (it couldn't bring in the roof with it.) I put two lag bolts through to help hold the top of the post together.

After that day of blood sweat and tears this issue hasn't made it to the top of my list again, but as it hasn't fixed itself, I'm getting ready to go at it again. I've got some more of those "L" brackets I salvaged years ago, but I have also considered running a cable through as I've seen done in other barns so that I can get the pressure to the outside of the post. Any ideas would be helpful.

[Prizl tha Chizl]

 

 
I'm not sure if it's going to be clear in the photo after resizing, but this is a powder post smorgasbord. They've mostly stayed out of the upper frame, but many of the joists and one other beam seem to have a lot of habitat, maybe because it's so damp down on the dairy floor. 

Basically, I'm not sure how to decide when damage is bad enough to need to replace a beam. It doesn't seem like an impossible feat, but it's a big job for me, and my main two helpers are still six or eight years from being beam hoisting age. I do plan to treat the entire frame with Tim-bor or Boracare but I wonder how they kept these guys out in the old days, did the whitewash kill them?

I'd like to set up a beamery down here and have a 16x24 salvaged aluminum bridge crane I'd like to set up to move timbers around, but don't think I should start hanging stuff from the ceiling if I have structural repairs to do.

[Woodrow,John]

These two rotten tenons are in the bents next to the hay loft door. The bottoms of the rafters had all been sistered on by a previous wood butcher. The beam they rest on needs to be replaced, as well as the floor joists immediately below, but I think this is my most pressing issue.
So this one is on its way.

 
This is one that I "repaired" 6 years ago. I used a come along and chains wrapped around that steel rod to pull the tenon back into its mortise, (a good 5 or 6 inches.) with about an inch left to go, the top of the post began to split where it was joined to the beam above it, (it couldn't bring in the roof with it.) I put two lag bolts through to help hold the top of the post together.

After that day of blood sweat and tears this issue hasn't made it to the top of my list again, but as it hasn't fixed itself, I'm getting ready to go at it again. I've got some more of those "L" brackets I salvaged years ago, but I have also considered running a cable through as I've seen done in other barns so that I can get the pressure to the outside of the post. Any ideas would be helpful.

Hello, First time posting so we will see how this goes. Your fix on the first bent is alright but preferably you would want a "saddle" wrapping around the backside of the post and a shear plate with rod through.(google "shear plate Portland bolt" and it should come up)
That way you spread the stress out over a larger surface area. Some of these specialty parts can get expensive though a 3/4x2" threaded pipe bushing could do a very similar job at 1/10th the cost.
 It's a beautiful structure and it's awesome the work you have done!!!!!

[Don P]

What you'll normally find is if you run a a tempoary strongback under the ridge, a firm place to stand and lift the ridge as you pull the side in it will often come back together without tearing or much trouble. By simply pulling the sides together you are forcing it to lift the roof, that is a serious fight. Lift and hang the roof a bit, then pull the sides togewther and repeat till happy, then secure.

Welcome John, well said

On the ppb's, I'd at the least replace the lower bolster on the hung beam but if it all looks like that, that barn may be at the end of its useful service. Get opinions from some pro's before making those decisions.

[Prizl tha Chizl]

Thanks so much for those pieces of advice. I'll spend a bit more time thinking on it before I take any action, but a few things for now.

I see the logic in lifting the roof, your comment made a little light bulb pop up above my head, ("oh yeah, of course!") which quickly turned to a rain cloud, ("how the hell are you gonna get way up there?")  It is a long way up to the ridge, and I don't understand the forces at work here well, but if I support that strong back from the floor with this type of truss aren't I working against myself? (Or does the floor load really apply no tension to those upper beams, all of its force  being transferred through the diagonals.)

I actually have a handful of antique shear plates from a friend who's a metal junkie. Until your comment I didn't see why they're better than a washer, but I think I get it now, a washer end up turning into a wedge,  (or cone, rather) the shear plate grabs onto a whole bunch of fibers a distance away from the bolt hole.

Re: PPB. The picture is of the worst spot. Some of the joists look pretty ugly, but the other beams and bolsters are relatively unscathed. I think I knew inside that that bolster needed to go, but just had to have someone else tell me.

I'd gladly get someone out here to look at things. Any ideas on where to find an expert in the area? I'm pretty sure that hiring out a restoration is out of the budget for now. But paying someone qualified to look at it could be something we could afford.

Either way, my first job is spending a good week sorting through and clearing out all the crap that has piled up out there. It's amazing what having a roof that doesn't leak will do for a person's junk pile!

[Don P]

You've got it, lift the ridge from the ground, the loft floor unloaded, it may take removing some floorboards to get the posts through. You can also shore under the floor, I'd give it a little jack up onto supports. Then from directly above that support continue up with a column that can take substantially more than the load you are looking at without buckling. Calcs are in the toolbox at the bottom of the lefthand column on this page.

We almost have a house down on its new foundations, rigging is one of the more time consuming parts of the job. In the quiet times while doing the grunt prep work in there, sit, study and do nothing until you understand how the loads are flowing down through the frame. Then decide how to safely shore and support what you are working on. Needless to say when you lift off of supports gravity is trying real hard to put it down anywhere. Spend more time bracing than you think is needed, then throw 2 more. The greatest thing in that regard is a battery impact and multiple sizes of structural screws. You can add and remove braces in moments now that used to take much more time.

Here I was replacing the sills and foundation. The inboard posts, treated 2x12 and scabs under lumpy log joists supported the floor. The outside posts support the wall, 2nd floor and roof. The new sill is loaded and ready to jack into place.



 
I think I've jumped a section down and set up again. This alongside the basement girder, and you can support the floor while replacing that bolster or girder and bolster.
I'm not allowed to trust the few remaining log joists in ours, or any of the floor framing, I've dropped the girders and run new joists alongside everything. All depending on use and condition you might consider that.


 

The reason the tenon to post top blew is the roof is really inadequately tied. When it is lifted and pulled back together a beam outside of the top plate along each side under the eaves with cables across is another way to take the entire spreading load off those compromised joints.

Looking and rambling.
The truss is actually a 2 function combined assembly. The angled struts, bolster tie and hung girder are the truss. it is riddled but holding, I see sag in everything so assess. The upper beam is the roof tie. Its connections have failed. Figure out how to retie it better, could be another floor up there...

@Rooster

I'd gladly get someone out here to look at things. Any ideas on where to find an expert in the area? I'm pretty sure that hiring out a restoration is out of the budget for now. But paying someone qualified to look at it could be something we could afford.

[beenthere]

Don P beat me to it, as member Rooster was (is?) in WI and very qualified in restoring barns. 

Check out his posts, a link to one thread here.
The Wisconsin Barn Preservation Program - Page 1 of 1

[Prizl tha Chizl]

 

 I  Haven't heard back from rooster, but his profile says he hasn't been here since March, so he probably hasn't gotten my message yet, looks like he probably deserves a good vacation.

I spent a good bit of time the last couple months cleaning out a bunch of junk, sorting through my lumber pile in the loft, treating some of it for powder post, moving the rest to the woodshed☹️, and finally installing a sub panel and lights and electric on the dairy floor. With a little help from the family, I finally got the crane hung today🤩 tomorrow I go into town to buy a used chain hoist for it. 

You'd still have to squint pretty hard to see this as anywhere close to becoming a shop, but I'm awful happy to have been able to carve out the time to even get this far, and spending all those hours in the barn has given me a lot of time to think about the steps I need to take next.

My main goal while I've got it all pretty clear downstairs is to power wash everything to knock of the old whitewash and soak it all with bora care. Debating whitewashing again when I'm done, but one step at a time around here. After that we're gonna have to hope it doesn't fall over while I save up some 💵, all that time working in there put nothing but a little echo in the piggy bank, and winter's gonna be a lean one if I don't bring home a little bacon to throw in the venison burgers.

[Prizl tha Chizl]

We're getting ready to mill the latest pile of salvage logs from our woods next week- most of it designated for the barn project. Poplar for wall and ceiling paneling, white pine for siding. Scots pine ceiling joists and mixed hardwoods, (oak, ash, walnut,elm,) for floor joists. Plus some walnut and pretty good looking cherry for who knows what future project.

I've been having a bit of a time sizing the floor joists. Right now they're logs flat sawn top and bottom, 6" thick, 24" on center. They span 160".  Can you feel them bouncing yet?

The easiest/ best looking match to me would be to leave the decent looking joists and drop in matching ones in between. I don't see a calculator in the toolbox for this, but am assuming that calling them 6x6 would be conservative.

I also guess that a shop should be figured for more load than residential, but can't find any numbers for how much. If I double my usual live+dead numbers to 100 psf, (20 dead, 80 live) I just fail in #2 mixed oak for bending, and big time in deflection. Backing the numbers off a bit it starts to look pretty good around 75 psf, but now I'm worried that I'm just trying to make it work because I want it to. Leaving the bottoms round also improves things quite a bit, but that calculator doesn't have a place to plug in the dead load. I guess that means I'm ready for advice from somebody with more than me.

[Don P]

Going back a couple of posts.
While we were at the cabin for a delayed reunion, late in the evening Dad and I were deep in the lime cycle when the last BIL drifted off  :D.

I sort of remembered whitewash being the waste product of carbide gaslight. Dad confirmed but also said the acetylene for the torches at the local gas station was produced by a carbide generator out back as well. The whitewash around the islands and station was the lime from spent calcium carbide. I'm sure a lot of whitewash was simply slack lime, slaked lime. I see the mason jar of woodstove burnt limestone 2 years ago is still slaking on the file cabinet.

You're on the right track. When the bottom of a round log is abused by saw or axe the fiber that causes the strength increase in the log calc has been cut. Use the heavy timber design values. And before I ran into the log beam and sawn log beam equations the engineer at one of the WI log home companies showed me the inscribed square method.. He would look at the small end and, well he was conservative, he stepped 1" inside the bark and drew a circle, then inscribed a square inside of that. He calculated his beams around that dimension using heavy timber design values. I called cranes and didn't complain.

Use determines design load, figure out what is going to be on that floor. The farmhouse went to 100psf when it became a museum. I'm girdered under it with no 2x10 floor joist spans over 8' and you could do auto repair on it. I put 2x10s alongside of 6" deep log joists and halved the spans. Inefficient but easily documented. I just added the log joists to the dead load. The public wouldn't see the underside and its bombproof.

If you want to get technical move from the IRC, the residential code, to the IBC, the building code... but you are going to be in the clause that says "do what the engineer says". The engineer asks you "So, what are you putting on that floor" and he guesses at it. Since its ag, you get to guess if you want to . I've seen numbers for hay as high as 300 psf in a tall mow.

Any increased dead load is adding to the hung load! I'm not remembering this closely or crawling through the building... trace the path, I'm seeing blown post connections. If the floor is suspended from the roof and driving load at the posts , think through it before adding load.

[Prizl tha Chizl]

Thanks for the thought out response, Don. I haven't "finalized" the shop design, but I've more or less figured out what I think I'll be able to fit in there, what the tools I own now weigh, and what it might add up to if I end up affording the tools I'd LIKE to put in there. It worked out to less than I was figuring in most of the shop, but with a lot of the heaviest pieces centered over the middle joists. Luckily I'll be able to park my 600 lbs pile of lathe with one half over the limestone foundation, so hopefully that will cut down on vibration, (I can't use it where it is now, it bounces too much! Considering this, I'm going to put my best timbers in the middle, and carve the weight limit on the wall so I don't forget when I win a shopping spree at the antique tool shop.

The blown posts are on the cut list, as well as the failed 8x8 bolster in the bottom chord of that King post truss, i think I'll try 8x10 this time. The trusses sit on the masonry wall (no added load to roof, though the truss will also carry the shop ceiling.)

One solution that's out for the floor is reducing the span, I need the space below to remain open and unobstructed for beam work. ButI don't think that's going to keep it any prettier down there. I don't have enough smaller diameter hardwood logs to match the original equipment, so I'm probably going to end up mixing in some flat topped pine and squared hardwoods as well, unless it decides to finally freeze up enough for me to get in the woods again over the weekend.  

A couple of questions for when I go through the numbers again with the logs I decide on. I noticed when I was playing with different loads that the higher percentage of dead load I had in the total, the less problems I had with deflection. Is this because the dead load is already "using up" some of the joist bounce? Can I count on this to help reduce vibration? Or are there other ways I should do that, like use your "harmonic resonance" design numbers? Can I add the (i think 15%?) bonus for repetitive members with my now 12" OC just spacing?

To answer the other wonderings, what I'm using for whitewash is hydrated lime I've had mixed into a putty in a plastic barrel for a couple of years. I thin it down until it just covers the print on a sheet of newspaper and apply it liberally. Still no idea if it helps with the PPB, but it's almost as fun as Tom Sawyer said it was gonna be. Grandpa described the lime pit to me on his home farm, but if he mentioned how they cooked down the rocks it escaped me. You and your mason jar got me thinking of throwing a few chunks of limestone (or a few shovelfuls of gravel) into the middle when I build our annual solstice bonfire out of the slab pile next week, though. I'll let you know how it works out.

[Don P]

I guess "properly" you back out the dead load from deflection calcs. Deflection is a serviceability rather than a strength check, it is interested in live load deflections. In some calcs I was more conservative and lump DL in with LL when doing the deflection checks. Very often deflection is the "control" when you are designing something. In a barn I am most mindful of strength, but I can say, a swaybacked shop is no fun.

[Hilltop366]

We use to have a 30' x 30' building (coach house) at a rental property that had the second floor centre beam held up by metal rods. It had a pyramid hip roof.