Rounded roof

[wantacoe]

I had a post here last year asking info on a round steel roof. I went through my user cp and can't find it. Someone shared a link from a place that specialized in that kind of roofing. Attached pic is the building I am working on. The original roofing is 5' wide aluminum. Thanks for any help.

 

[JoeMcGov]

Please attach pic.

 

[readhead]

no pic.

 

[wantacoe]

Pic won't attach, still working on it.

 

[wantacoe]

Pic up now.

 

[readhead]

Most architectural metal roofing suppliers can provide rolled panels.

 

[dfiler2]

Regular pole barn steel will easily fit that curve. two quonsets were done near me a couple of years ago, I was amazed at the curve, much more than the one in the picture.

 

[Marctrees]

https://www.garagejournal.com/forum/showthread.php?t=400215&highlight=aluminum+roof

 

[wantacoe]

https://www.garagejournal.com/forum/showthread.php?t=400215&highlight=aluminum+roof

Thank you Marc, I spent an hour looking for that!

 

[ZRX61]

http://www.drexmet.com/met-fab/curved-panels

 

[rustyjames]

Merchant & Evans rolls panels, but shipping them would be a bit of a distance.

 

[Marctrees]

I re read my post in the original thread,,, and want to post it here cause I believe it is the logical way to proceed.

Notice I say the thinner gauge, AND lowest rib height style.

Marc

Marctrees
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Default Re: Steal roof question?
I would find a local source for steel sheet panels...In your area somekinda "Farm Supply" and check out the lighter gauge smallest vertical ribs.. "Corrugated", not any R panel style.

I'm just thinking... the thinner the steel, AND even more.. the minimal rib height. I would think would bend easier.

Buy one sheet, then somehow try to duplicate approximate that radius to see how it cooperates... or fights you.

Like on a flat lawn w a few friends standing on 2x4 or something.

You could even get a taste of it at the yard before you buy.

Never tried it , just thinking, so I have no idea, buit would at least explore it.

EDit - I don't expect you to be able to smoothly actually "bend" it, but rather see how resistant it is to "Flexing"

Your radius is not all that tight, may, maybe, be possible.

Marc
_____

 

[Marctrees]

And of course you will be starting at the eave so panels overlap in proper direction,,, and if there is a bit of a step ... and there will be some at least... use the appropriate foam tape.

And NOT some chinese **** that will melt the first hot day.

Point is I would do mockup on lawn or driveway with just like 2 test panels purchased... then go from there.

I really think well worth the time and couple bucks to do the mockup of roof radius on ground.

Marc

 

[Marctrees]

In the other thread I sed - "The ridge sheet - I would not try to bend that one totally. but cheat by having **** seam at ridge and covering that w a "Ridge Cap" from any sheet supplier.. bent on brake in house like 20" wide x length of ridge to any pitch angle.

That will be WAY less stressful."

I really think that is a good idea, AND you could use that to your advantage and end up w a ridge vent if you use the coarse Scotch Brite type of closure strip.

Of course, IF you are re covering what is currently in place... and that's a whole nother question... If you want to vent it, you would have to cut like a 6" wide slot down the existing ridge of the building.

Interesting project.

Marc

 

[Bert_]

In the other thread I sed - "The ridge sheet - I would not try to bend that one totally. but cheat by having **** seam at ridge and covering that w a "Ridge Cap" from any sheet supplier.. bent on brake in house like 20" wide x length of ridge to any pitch angle.

That will be WAY less stressful."

I really think that is a good idea, AND you could use that to your advantage and end up w a ridge vent if you use the coarse Scotch Brite type of closure strip.

Of course, IF you are re covering what is currently in place... and that's a whole nother question... If you want to vent it, you would have to cut like a 6" wide slot down the existing ridge of the building.

Interesting project.

Marc

I'm no expert but a seam at the ridge sounds like a leak waiting to happen. The roof is basically flat there. I would want a nice long sheet centered on the ridge.

 

[wantacoe]

You can sort of see in the pic but the roof is missing about 12/15' off the back. The roof is 3 pieces, one on each side and the center one overlaps each of them. I am getting too old to be on roofs, especially a round one like this. I think it is going to cost more to fix it than it is worth. The building isn't much but I just hate to see it deteriorate any more. It was like this when I bought the place 2 years ago.

 

[Marctrees]

Bert - Don't forget that virtually all R panel roofed buildings use a ridge cap.

Roof sheets **** at ridge, often w a space like ballpark 6"... then is covered by a wide ridge cap bent to pitch... and then applied using vented closure if desired... or solid foam closure if not venting.

You probably know this but may have misunderstood what I meant.

Marc

 

[Bert_]

Bert - Don't forget that virtually all R panel roofed buildings use a ridge cap.

Roof sheets **** at ridge, often w a space like ballpark 6"... then is covered by a wide ridge cap bent to pitch... and then applied using vented closure if desired... or solid foam closure if not venting.

You probably know this but may have misunderstood what I meant.

Marc

Most roofs have a constant slope. A round roof like this has good slope in the bottom 2/3 but is almost flat for several feet in the middle. Even the slightest wind would blow water under the ridge cap. Unless you have a 6 foot+ ridge cap I just don't see it working on roof like this.

I will say I have seen building with a much tighter radius than this re-roofed with regular old ribbed steel, bends to the curve with no problem.

 

[readhead]

Most R panel roofs use a crimped ridge unless a ridge cap is specified. Three pieces or more is pretty typical for a rolled roof. The reason the sheets should be rolled is the ends of the top sheet won’t want to pull down tight.

The easy solution would be a rubber roof.

 

[Marctrees]

Bert - I see your point... Ya, I guess the ridge cap if seperate would need to be quite wider than typical.

Good point.

Marc

 

[Marctrees]

Puget Dude - Where are you ?

He knows about this stuff.

Marc

 

[ZRX61]

I want a shop with a roof like that just so I can use Belfast Trusses in the construction.

 

[PugetDude]

Several ways to do this...

1. Use 7/8" corrugated and work it from the eaves toward the gable, 10' sheets and lots of screws. A low-rib corrugated panel will conform to a slight radius better than a trapezoidel or box-rib panel. Center the top sheet and lap it over the eave sheets.

2. Crimp curve to the proper radius- absolutely required for tight radius bends, Curveline has been doing this for years for high-end architectural applications. If you just need a loose curve and aren't too picky about consistency, it can be done by progressively bumping the upside down panel in a hydraulic ridge cap press with a set of profiled UHMW blades. Most panel manufacturers have a ridge cap press to do the crimped ridge that Readhead described. It would take some trial and error but a skilled machine operator could figure it out.

3. Find a local building panel supplier (not a rep or dealer) and ask them how much dive they can induce into the panel as it's being rollformed, it doesn't take much to get the panels to fit a large radius. Dive means the panel is trying to curve downward as it comes off the rollformer. I've also seen it done by reverse rolling the material with a lot of ski in the panel; i.e. the panel wants to roll up as it comes out of the rollformer. R-panel can be rolled upside down this way to get the finish color on the underside of the panel. Ski is easier to induce than dive, but a skilled operator can generally influence either- since they normally strive to take it out and produce a perfectly flat panel.

4. Agree with Readhead- I'd use three sheets to do this roof. One from each edge, with a top lapped sheet over both.

Good luck, update us on the results.

 

[Marctrees]

Dang !

Now that's a great post !

Marc

 

[readhead]

PD is absolutely right about ski and dive. I had a local roller put some ski in some panels we used on a mansard we did once. It needed just a little help to follow the curve. Since the factory set up their machine the operator didn’t understand that he could manipulate the rolls to get different results. I suggested that he call the company and one of their technicians walked him through the adjustments. Came out great and the operator learned new things about his machine.

 

[Marctrees]

Very interesting.

So this means like any and all joints that roll panels have the ability to put at least a little bit of curve on them...with the basic standard equipment... assuming an intelligent and willing to experiment operator ?

Marc

 

[readhead]

Yes to a point. Most don’t know how and probably shouldn’t. We aren’t talking a lot of curve. There are other machines for that. PD could clarify that better since he is on the equipment side.

 

[Marctrees]

The building seems to be around 30' wide. so 3 panels would be "easily" manageable.

Marc

 

[PugetDude]

Grain bins are a great example of what can be done to curve a formed panel. These are done in a 3-roll bender with a set of profiled rolls that matches the corrugated panel. Can be up to ~1/4" thickness without deformation.

Architectural curving is another matter- if there are steep angles on a trapezoidal panel it is generally done with a crimp curving machine, as the sides of the trapezoids will collapse if there is no place for them to go when the flats are being rolled.

https://www.curveline.com/

 

[PugetDude]

Very interesting.

So this means like any and all joints that roll panels have the ability to put at least a little bit of curve on them...with the basic standard equipment... assuming an intelligent and willing to experiment operator ?

Marc

To a point. A slight curve is possible, within the adjustability of the equipment, the rollformed panel height, and how steep the angles are on the trapezoids. You'll have better results with a sinusoidal corrugated panel than a steep box rib panel.

A good rollformer has pass adjustments for panel ski and dive- (designed to reduce or eliminate it) so it takes an experienced operator to know where to go to induce it- and then go back to running nice flat panels for everyone else once he's done with your ******* order.

 

[wantacoe]

Thanks for all the help. I took more pics and checked things out today. The building is 40x60. The panels are aluminum and are 52" wide, not 5' like I said before. As far as I can tell they are about 14' long. The former owners let this go to hell when they built a new pole barn about 50 yrs ago. (which they also let go to hell)
About half of the roofing panels are bad and a lot of the purlins are rotten. I need to concentrate on getting the pole building fixed before I do anything with this. I think it will cost too much to hire someone to do this and I don't know if I am physically capable of getting on that roof. How do they work on these roofs? No way you could stand on it.

 

[Marctrees]

Well, the "No way you can stand on it" is totally subjective.

Don't get me wrong... I would not go up there... but there are plenty that do it like a walk in the park.

I myself am not Man enough... Just look at my Avatar !!!

I mean at least if not totally rotted... If so, then I dunno.

Are your panels REALLY Aluminum ? ? ?

Marc

 

[wantacoe]

Well, the "No way you can stand on it" is totally subjective.

Don't get me wrong... I would not go up there... but there are plenty that do it like a walk in the park.

I mean at least if not totally rotted... If so, then I dunno.

Are your panels REALLY Aluminum ? ? ?

Marc

I think they are aluminum, I am going out there tomorrow again and will take a magnet to check. I can fix the purlins from inside on a ladder but getting on that roof is too risky for this old man.

 

[Marctrees]

Ya, take the magnet.

I have never heard of AL roof sheets, but I in reality do not know EVERYTHING.

Do NOT Tell my Wife... I have trained her to believe I do.

Marc

 

[Marctrees]

If you are not steady confident on a ladder... I know I myself no longer am... Do NOT do this off a ladder.

You can TOTALLY **** yourself up BIG SERIOUS falling off lower rungs of a 6' step ... let alone this height.

Find a buddy w a scissorlift, AND a helper on the ground.

Marc

 

[PugetDude]

Just look at my Avatar !!!
Marc

No.
Just no.

 

[Marctrees]

Just for Puget...

 

[wantacoe]

Aluminicity confirmed. I have seen this "dimpled" al before, not sure where.
I was at a place that forms metal today getting some stuff for my pole building. I asked him if he had anything for this building. All he had was some corrugated steel like this one at Menards. Menards says it is not for roofing though.

 

[Marctrees]

Menards does not have plain simple Galvalume Corrugated ?

I would expect they would at least in the thinner 29 ? Ga.

Marc

 

[PugetDude]

Aluminicity confirmed. I have seen this "dimpled" al before, not sure where.
I was at a place that forms metal today getting some stuff for my pole building. I asked him if he had anything for this building. All he had was some corrugated steel like this one at Menards. Menards says it is not for roofing though.

Kaiser Aluminum used to distribute the dimpled aluminum sheeting out of their Spokane WA facility in the 1950's and 60's. In the 70's Gifforfd Hill was selling it out of Grand Island,NE, Visalia, CA and Spokane. It was fairly heavy gauge by today's standards. Pre-painted galvanized steel made the uncoated (and expensive) aluminum obsolete in the mid 70's.

Bad news is that your roof is probably 60+ years old and at the end of it's useful life. Good news is that the scrap value of the aluminum will go a long way toward a new galvanized steel roof...