Metal Roofing Questions

[Ken524]

I was shopping for metal roofing today and found that Lowes carries galvanized corrugated roofing panels and ridge caps. That would look pretty cool with my design. I'm also looking for colored metal roofs.

Any thoughts on using bare galvanized panels for the roof? Does it need to be painted or sealed for long term wear or is ok to just leave it the way it is?

When I screw this down to the steel studs, do I need to put sealant of some sort over the screws?

I'm really getting into unknown territory when it comes to roofing.

[jahysea]

Re: Metal Roofing Questions

I have a corrugated metal roof with matching ridge caps, exactly as you describe. It's only been through one Northern California winter but it looks bulletproof to me. I screwed it directly to the metal studs I used as rafters. The material is designed to not be treated with anything. I believe it will look as good as new in 20 years, it certainly looks fine on very old barns in our area.

Our local supply yard had some rippled wood trim cut to fit the ripples in the corrugated, I placed those strips along the lower sides at the bottom so that there wouldn't be any gaps along the bottom. I believe this is the only wood in my entire structure. I covered it with stucco.

I was able to buy a box of screws designed for attaching the corrugated roofing. They have built in rubber washers to prevent leaks. I drilled guide holes and screwed them in.

You can see my roof here: http://www.fornobravo.com/forum/phot...ndex.php?n=865

or the building thread here:
http://www.fornobravo.com/forum/f8/s...elena#post6488

Happy to help with any questions.

[Ken524]

Re: Metal Roofing Questions

JC,

I had completely forgotten that you had used metal studs. I went back and studied your project. It answered a LOT of questions for me (thank you!).

One thing I couldn't figure out is how you weatherproofed where the chimney exits through the metal roof. Could you tell me how you did that (any pics?)

Thanks a million! You oven and enclosure look wonderful.

[jahysea]

Re: Metal Roofing Questions

JC,

One thing I couldn't figure out is how you weatherproofed where the chimney exits through the metal roof. Could you tell me how you did that (any pics?)

Hi Ken, THAT is a great question, and when you solve it I may just copy you! :-)

.. I went through last winter having just cut square holes in the roofing around the chimney. They were irregular and rough as I was originally intending them to be covered by some flashing. I spent the better part of a morning one day trying to build that flashing and gave up, thinking I'd get it made somewhere. When it rained, a little water would get in through the gap and presumably soak ceramic blanket I wrapped the lower part of the chimney in. We have no substantial frost issues, so other than seeing a little steam one use after a particularly large rain, no ill effects. The first thumbnail below is about the best closeup pic I have of that original state.

After going though an entire winter and summer, I finally decided to just replace that section of roofing and cut far more carefully so that the roofing would come right up to the chimney. Caulked with fire barrier sealant (3M product CP25WB+). If the sealant breaks down from UV exposure over time, I'll recaulk and cover it with a small amount or mortar. I put in another thumbnail up close of the caulk.

I also added a pic of the bottom of the roofing where I stucco'ed up to the roofing.

I consider it a suboptimal solution, but quite workable for my climate. If I lived somewhere with serious frost or more rainfall I would get flashing made or find some other solution for certain.

[Ken524]

Re: Metal Roofing Questions

Very helpful. Thanks so much for showing me!! Due to my climate I'll likely start out with your plan and add flashing.

[Guerito]

Re: Metal Roofing Questions

Ken,

If you don?t want the industrial galvanized look, there are options. I did a quick search and found all kinds of stuff on corrugated roofing panels. It looks like you have a choice at most places between a dozen or so colors.

Metal Deck, Purlins, Metal Roofing and Metal Siding in Stock.

Corrugated Industries Inc. - Metal Roofs and Buildings

Corrugated Metals Industrial Roofing and Siding

Good luck,

Guerito

[Ken524]

Re: Metal Roofing Questions

Thanks Guerito. My spouse pretty much vetoed the galvanized look (JC knows the feeling). I found some places in town that have some colors. I'll head out this week and check prices.

[Archena]

Re: Metal Roofing Questions

Um, you couldn't just buy the flashing? I thought it was sold as a prefab (at least in terms of width) product? I remember it being pretty thin gauge so working with it shouldn't be that hard, should it?

<insert scratching head smilie here>

[Ken524]

Re: Metal Roofing Questions

Archena,

As a matter of fact, I was looking at rolls of flashing today at the Depot. That's probably the way I'll go; as well as some furnace sealer or some other appropriate weather-proof goop.

[Archena]

Re: Metal Roofing Questions

Okay, cool - I was beginning to think I'd lost what was left of my tiny mind...

[Hendo]

Re: Metal Roofing Questions

Any thoughts on using bare galvanized panels for the roof? Does it need to be painted or sealed for long term wear or is ok to just leave it the way it is?

When I screw this down to the steel studs, do I need to put sealant of some sort over the screws?

Ken,

When looking for fasteners (which have neoprene washers), you may be able to score some with a drill tip, which obviates the need for pilot holes as the fastener drills its own. I have used these after simply penetrating the steel roofing with a sharp bullet punch to locate the fastener ? works a treat!

Remember to get long fasteners, as roofing sheets are fastened through the crest of the corrugation, not the valley. You probably know this, but I?d love a dollar for every home-built roof that has the fasteners in the valleys ? and leaks as a result!

Cheers, Paul.

[Ken524]

Re: Metal Roofing Questions

Paul,

Actually, I know very little about this stuff and likely would have been one of the half-wits that puts the fastener in the valley if you hadn't told me

I'll look for the fasteners with the drill tips. That sounds like a great idea.

Thanks for the info!

[jahysea]

Re: Metal Roofing Questions

Wow.

1) Paul. I needed you around a year ago.. I guess I'm a half wit because I put my fasteners in the valleys. Seemed like putting them in the peaks would crush the peaks. I guess you just stop screwing before tha happens. I'm probably OK leak wise-as the crown flashing covers the screws up top, and the ones at the bottom are, well, at the bottom.

2) I think you guys are missing the point on the flashing. Of course I bought a roll, I wasn't trying to manufacture flashing. It's cutting/glueing/screwing that flashing together somehow to make a watertight joint around an irregular chimney centered on the peak of a roof that is made from irregular corrugated sheeting. I tried lots of angles, but glue woudn't really hold the stuff together well, it doesn't bend all that easily other than in straight lines, etc etc. If one of you is able to make it work, take some pics and I will happpily emulate!

[vincent]

Re: Metal Roofing Questions

hope that i'm not too late to share a bit of info..there's a company called Fabral that manufactures a variety of metal roofing..there is a nice color selection and its available in steel and aluminum with a variety od accessory pieces..and believe it or not..when i've used it you can order it the exact length thats needed..no field cutting the panels..if youv go to their site Fabral they even have schematics on doing the chimney flashing..ridge vent..ect

[Acoma]

Re: Metal Roofing Questions

Vincent, great find! Ken, you should see this site.