Thread: American barn style?

"American barn" seems to have a specific meaning for y'all there in Oz, but I'm not sure what you mean. American barns come in lots of flavors:
Barn, midwest.jpg

Barn, clerestory.jpg

Barn, bank.jpg

And, of course,
Barn, broken down.jpg

Some description might help your international members to weigh in on the topic.

I think the OP is referring t the second of the above pictures.

Thats the style of building that SWMBO wanted to have for my new shed so she could have the top middle part as her "studio" but Council would not approve the design as it went over the height restrictions for "sheds" in our are. We're ~1km from city centre on a 1/8th acre block. Instead her stuff occupies 2 bedrooms and the old sitting room in the house.

"an American barn style shed" refers to the architectural style in the second picture. It has nothing to do with geography.
To clarify further, I am talking about steel sheds.

It has 3 bays across the width and as long as you like. The center bay being higher than the 2 side bays.

I can build it up to 4.5m at it's highest point and stay within council rules. I can build it higher but that will incur additional costs from the council. Which might happen - it depends how high I need the middle bay roller door. In my planning zone the local shed builders call this a council wealth tax. Because it is almost always granted but they charge extra to "relax" the rules. Hence it is considered to be a bit of a scam.
However the other problem with going higher is that the erection costs go up.

For woodwork, posts every 3.5m are a nuisance but probably bearable.

For car restoration (IMHO) they would be a nightmare. I use dollies, and also a hoist that can have wheels attached, to enable me to spin cars around when I'm working on (or painting) them, and also to slide cars up against the wall if I need more room for another project or if I'm waiting on parts. Posts every 3.5m would make that very difficult, meaning the car would potentially have to be moved out of the shed to be turned around or shifted from one "bay" to another. Not too bad if the car is mobile, but more tricky if it's a bare chassis on a rotisserie or it has no gearbox.....

However, people work in far smaller spaces and manage to survive. I used to restore cars and build race cars in a single width x double length garage, and thought nothing of it because it was "normal". After getting used to large open sheds, I'd rather not go back. But I could if I had to.... Needs must when the devil drives!

I guess you need to consider what you might want to use the shed for the future, honestly appraise whether saving a few $ now will create problems down the road, or if saving up for another (however long it takes) to get what you really want/needs is a better approach. Then, and only then, do EXACTLY WHAT YOUR WIFE WANTS TO DO.......

Thanks Warb, that is exactly the kind of issue I wanted to hear about. I have never done much with cars before but I am now getting really interested in classic cars and restoration. I'm going to set aside approx 60m2 for that.

Also I'm interested in one day doing a caravan or motorhome project.

Hi Dave,

My second AB is now about about 8 months old. My first was up for 9 years in the back yard of a metropolitan 1/2 acre block in the eastern suburbs of Melbourne. The second is on 2.5 acres on the edge of a country town.

The first was 16mL x 12mW (5m Centre and two 3.5m skillions) with side walls about 4m H and ridge line at about 5.5mH. Portal separation was 4m for 4m long bays. There was a full height container door in the centre front wall and a pair of 2.4 x2.4 rollerdoors in the front on either side, plus another in the back wall on one side to have one skillion as drive through to access the rest of the yard, and the centre and second skillion back walls blind. Height was selected to allow storage mezzanines full length along both skillions, and provide for a car hoist and caravan/rv in the centre section.

The second is 16m x 13m (5m Centre and two x 3.75m skillions) with 5.5m side walls and a ridge at about 7.5mH. Portal separation remains at 4m, but the barn is engineered for full length mezzanines on both skillions, with 2.5m headroom at floor level and 2.4m headroom for both mezzanines. Bearers for the mezzanines are 300mm C channels and joists are 200 Z's. The mezzanines are engineered for 1T per sqm loading. Floor level accommodation plan is 3 bays of one skillion to be a woodwork shop (12m x 3.75m), with the forth bay for metal machining (lathe, mill, maybe a surface grinder), with the whole mezzanine above for storage area, the central bay being a 2 post hoist and van/rv storage, and the third bay being car storage with an office/library lounge and model room on the mezzanine. Thinking about only fitting out the mezzanine that side for only 11m length and installing a 4 post hoist at floor level rising up into the mezzanine level to obtain extra spot for another car.

The 5m centre allows me to rotate cars on dollys easily and juggle them around. At 4m portal spacing, the presence of uprights is not an issue to me generally, but it could become one with 3.5m spacing, or because the overall barn you are considering is narrower than mine. Remember that uprights and girts on the sides intrude into you skillion floor area, and those in the centre section intrude into the central floor area. For my original barn, that was 265mm in from the wall surfaces in both the central and skillion areas, for the new barn it is 320mm due to larger section girts.

When allowing for roller doors etc, they generally use the portal frame uprights to support one side of the doors, and add an extra upright to support the other side, or if the door is to be centred in the bay, they add two uprights to support it. All of this can be an issue if you need to fit 3 doors across a 10m span. Possible options would be to have the structure engineered and permitted for full length and a bit wider than your initial estimate to accommodate the doors, but initially erect one or more less bays in length on the basis that you can add the remaining bays later when funds become available. I would also consider adjustments to the length to obtain more economical portal spacing. Your 25m length would require 8 portals (7 bays) at 3.5m spacing, whereas 24m length would require 7 portals (6 bays) at 4m spacing which is definitely doable, saving the cost of a portal frame, it's footings and it's erection costs.

Hope this helps to firm up you intentions.

I work out of an AB. To overcome the maize of posts I ran an RSJ for the main ridge at 7.5m long with only a 150 x 150 x 5mm SHS post up each gable end. This gave a clear 9m x 7.5m floor area to the posts supporting the wings. The RSj has a trolly with a chain block fitted for lifting. The wing posts are at 3.5 centres and the wing purlins span 4.5m each. Total shed size is 18m wide x 7.5 deep. With a rolling lifting block down the centre of the shed.There are four door openings; one each side of the main ridge post and one to each skillion wing. Each door is 4m wide. Easy for truck access and fork lift unloading. Long timbers are easy to spin in the 9 x 7.5 bay. All machinery and benches are on wheels.
Roof is sarked and insulated(most important.)

Thanks Malb. That is really helpful. The shed guy did point out that the bays can be anywhere between 6m and 3m. However it could be that at 5m and 6m bays they have to use the heavier steel and thus the erection costs go back up. I need to check. The point of the American Barn style was to reduce the erection costs.

I like your idea about adding bays in the future. I had thought I could perhaps have the office part as a separate shed in the future, when I could afford it. Not only to spread the costs over time but also because then the floor could drop a level. The longer I make the slab the more earthworks are required. Thus far I have assumed that would too much cost more to do at two levels.
However your idea is basically prepare the one slab but only erect some/half of the total planned structure. I hadn't thought of that.

I really like the RSJ crane idea. In my case, by the time I leave a 4m side setback, then a 10.5m wide shed, I'm getting close to the house. So I'm limited to 3 bays, not much more than 3m wide each. I could make the middle bay 4m and the side bays 3m. Although as malb pointed out the posts mean the real width is less than that.
Lengthwise I could probably request 4m spans to reduce the number of posts.

Is the saving of the barn style shed enough to be happy having smaller roller door openings and posts throughout your shed?
Your bays may feel a bit narrow working on a car or caravan in them ??

Just a note regarding the RSJ crane concept. It has two significant drawbacks. The first is the practical restriction that the load is "fixed" in the center of the shed, there is no ability to move sideways. The second, and potentially more major issue, is that the crane is structural to the shed. This means that any damage caused by overloading the crane now becomes damage TO THE FRAME OF THE SHED. Anyone (sensible) who uses a crane is aware of the limits of that crane, and some people might even try to stay safely within those limits, though in my experience most people fixate on the job and forget the physics! However there are situations where a crane can be over-stressed by mistake - I have watched people try to pull engines that still have bolts holding them in, or lift things off utes that are still strapped down......

Typing this reminds me of a similar event, that by chance also relates to sheds. When we rebuilt the large hayshed on my property (burnt down before I owned it), my engineer friend decided we could use some "2nd grade" steel posts that were still well within specification for the task. At that time steel prices were going up 5% per week (it was the "let's rip off the Chinese" phase of steel manufacture in Australia), to the extent that we bought flat roll colourbond and stored it until we were ready to have it rolled in to corrugated because the prices were going up so fast! So saving money on the posts was worthwhile. Anyway, the truck with the posts showed up at my friends yard, and out went the forklift to unload them. Forks in, lift, and oh cr*p - the back of the forklift was up in the air. "Stupid truck driver has left the straps on the load". Nope, no straps...... Whaat?..... Further investigation showed that the "2nd grade" posts weren't truly "2nd grade", they were in fact some massively thick walled sections that had been ordered by mistake and then sold cheaply as "2nd grade" just to get rid of them..... Change to the "shipping container" forklift and we're back in business! It's now an ongoing joke when a sparky tries to fix a box to a post and looks bemused as he drills through 20+mm of steel.....

The point with the RSJ crane is that it's easy to keep pulling that chain until the roof falls in!!

You limit your crane by the chain block capacity. Only use first quality steel. The beam, posts and footings should be Engineer certified. The beam will bend if overloaded before collapse. A removable centre post increases the capacity if necessary to facilitate higher weight loads but does reduce travel to half beam length.
Whether a crane is part of the structure or not it makes little difference if the crane fails under load. The end result in either case could be fatal.
SWL's are there for a reason. Safety is YOUR responsibility.

Originally Posted by rustynail

You limit your crane by the chain block capacity. Only use first quality steel. The beam, posts and footings should be Engineer certified. The beam will bend if overloaded before collapse. A removable centre post increases the capacity if necessary to facilitate higher weight loads but does reduce travel to half beam length.
Whether a crane is part of the structure or not it makes little difference if the crane fails under load. The end result in either case could be fatal.
SWL's are there for a reason. Safety is YOUR responsibility.

Absolutely everything you say is correct, and I agree wholeheartedly. Unfortunately, for every person who follows those rules there is another who won't (probably not the person who originally designed and built the system and has full understanding of its capabilities), and a large portion of those who follow the rules on a good day will have a rush of blood to the head when they're in a rush, or just misjudge the weight of something. And there's always simple mistakes - a long time ago I watched a normally very safety conscious guy do a three point turn by reversing under a gantry, which sadly (and unnoticed by him) had a chain and hook hanging from it........ He towed the gantry across the yard, but imagine if it had been the center beam of the shed...

As you say, any crane has the same rules. The difference is that when the rules aren't followed with a standalone gantry, it doesn't destroy the shed. Assuming no-one is injured, it's much cheaper to fix a gantry than a shed!

Originally Posted by Warb

Absolutely everything you say is correct, and I agree wholeheartedly. Unfortunately, for every person who follows those rules there is another who won't (probably not the person who originally designed and built the system and has full understanding of its capabilities), and a large portion of those who follow the rules on a good day will have a rush of blood to the head when they're in a rush, or just misjudge the weight of something. And there's always simple mistakes - a long time ago I watched a normally very safety conscious guy do a three point turn by reversing under a gantry, which sadly (and unnoticed by him) had a chain and hook hanging from it........ He towed the gantry across the yard, but imagine if it had been the center beam of the shed...

As you say, any crane has the same rules. The difference is that when the rules aren't followed with a standalone gantry, it doesn't destroy the shed. Assuming no-one is injured, it's much cheaper to fix a gantry than a shed!

Warbs

To my mind, this comes back to the question "what if?"

I work in an industry that is fairly anal about safety to the point it drives most of us to distraction and I mean that literally in that it has got to the point where safety precautions are ticked off without paying much heed. If you go overboard with this or indeed anything it has the effect of devaluing the concept. I believe that you have to take responsibility for such matters yourself. Develop your own rules and follow them. You cannot second guess what another person will or will not do.

In a domestic situation there will be no rating on the beam in question, although no doubt the engineer can give you a figure and that will have a safety factor incorporated. By that I mean it will be rated to withstand a load without deflection. The beam will probably withstand a much higher load if deflection was permitted so it won't fail until grossly overloaded. As to collecting a loose and hanging hook I don't believe it is reasonable or even practical to consider every eventuality. I can already hear you say, "but it happened." Yes, and if you followed that line of reasoning, you would never take your car out of the garage, because arguably that is one of the most dangerous things you do and many of us do it absolutely every day. No indictment of your driving skills: but everybody makes a mistake sooner or later and those people are all around us as we drive.

Please don't misunderstand me: I am not advocating we should work unsafely and it is only right that you should bring the subject up, but there has to be a reasonable level of common sense.

Years ago I bought a hoist that was rated at one tonne. It is a three phase electric model of antique origin and has a travel facility as well as rise and fall. Four men would not be able to pick it up. It is a monster. I have never used it because I did not have 3PH power available. I can imagine that this style of hoist would suit a shed such as DaveVman is considering and rustynail described. Would we say don't do it because one day you might leave the hook down and reverse your car into it? I don't think so. It was originally used in a workshop that had a RSJ running all around the shed.

However, I absolutely take your point that we should be aware of safety: Probably more so than we do.

Regards
Paul