Metas roof to wood, screw placement, which camp are you in and why?

[Arky217]

(Should say Metal, not Metas but can't edit the title)

Although this doesn't have anything to do with tractors, there is a two year old thread that touches on this subject and I thought I would see what today's opinions are. My research on this reveals that there are at least two basic camps of thought on this, even by the manufacturers of the panels.

Some say that the panels should always be screwed down on the flats.
Others say that they should always be screwed down on the ribs.
Even others say a combination of the two.
Seems most manufacturer instructions say the flats, but I found one, at least, that says the ribs.

Some of the reasons for screwing through the flats are:
* The screws can not be tightened enough through the ribs without squashing the ribs.
* When through the ribs, the air gap between the metal and wood allow a leverage of the 'rocking' motion caused by the movement of the panels due to heat expansion/contraction.

Some reasons for screwing through the ribs are:
* If/when the screw backs out and/or the gasket cracks/deteriorates, the leak will be much greater if the screw is in the flat.
* If the screws are put through the outer ribs only (the ribs that overlap the adjacent panel), the screws can be tightened sufficiently without squashing the panels.

Of course, using standing seam panels would solve any fastener leak possibilities, but in my area it's twice the price or more.

I'm still undecided on this, but I'm wondering if the following method might be feasible on a plain roof with no gables:

Attach the screws along the eaves and ends of the roof (where the screws protrude into the open outside air and not into the attic space) through the flats every 12"
For the roof over the house itself, screw only through the metal outside ribs at 24" spacing. (In other words, screw only through the outer ribs where they overlap with the next panel's outer rib)
It just seems to me that if the metal panels were attached securely along the perimeter of the roof, then throughout the rest of the roof, that screws through the overlap ribs only should be more than sufficient to hold the metal down. And since the screws would be going through 2 ribs, you should be able to tighten them sufficiently without squashing the ribs.

I'm going to be putting a metal roof on my retirement home soon and I know that once I have the roof done, I sure don't like the idea of getting back up there to fix any future leaks (getting too old).

What are your thoughts on this subject ?

 

[beenthere]

Through the ribs. Less chance of a leak in normal, mild rain/snow.

 

[bdeboer]

I recently was told flats by an HD salesman quoting the manufacturer literature when I asked why they didn't stock longer screws. Not that HD is my first choice for metal, but they were convenient. If you are concerned with warranty (assuming they honor them better than shingle manufacturers) then I would do exactly what the literature says.


When I built my polebarn 9 years ago was told ribs on the roof and flats on the sides to hide hammer dents when using nails. The older metal roof pole buildings/barns I have worked on have them on the ribs. Most of these are nailed not screwed.

 

[dex3361]

I used the manufacturer recommendations and drove the screws through the flats. I had the same concerns as you. I searched every instruction page I could find and that is the conclusion I came to. I have a few instruction guides saved as PDF files if you are interested let me know.

 

[tommu56]

Fabral and Wheeler say, nails ribs, screws flat, and double up screws at the seams

tom

 

[alchemysa]

If you are talking about corrugated metal theres no way I would put it in the 'valley'. Screw heads through the peaks are much more water resistant. All the (thousands of) screws on our 4 metal roofs are on the ribs and we have no leakage. The rubber washers under the heads often break when installing. If you put them in the valleys you could have many small leaks and not know it til its too late. Screw heads in the valley will hold back leaves and muck too.

 

[Redneck in training]

We have metal roof and siding on our house. The roof is nailed trough the ribs. The nails are nailed in about 60 to 70 degree angle somewhat off center of the rib. Reason being the nail makes a dimple and it needs to drain instead of holding water. Nails are used because of self-healing properties of the roof sheet metal. The nail pulls the coating in the hole sealing the edge and thus preventing rusting. Screws might rub it off. Since the siding is generally dry it is screwed perpendicular in the center of the rib. My house was built by Morton buildings.

Morton Buildings - Pole Barns, Horse Barns, Steel Buildings, Metal Buildings, Storage Buildings, Farm Buildings

 

[two_bit_score]

(Should say Metal, not Metas but can't edit the title)

Although this doesn't have anything to do with tractors, there is a two year old thread that touches on this subject and I thought I would see what today's opinions are. My research on this reveals that there are at least two basic camps of thought on this, even by the manufacturers of the panels.


I'm going to be putting a metal roof on my retirement home soon and I know that once I have the roof done, I sure don't like the idea of getting back up there to fix any future leaks (getting too old).

What are your thoughts on this subject ?

Why not just follow the recommendations of the manufacturer of the panels you buy?

Do you really think you can devise a better plan than they did after all the research and investment they put into determining how to properly install their product to get the best benefit from it?

 

[Arky217]

Why not just follow the recommendations of the manufacturer of the panels you buy?

Do you really think you can devise a better plan than they did after all the research and investment they put into determining how to properly install their product to get the best benefit from it?

Possibly, yes.

If the manufacturer's 'research and investment' to determine how best to install their product is all that intensive, how is that for the same 5 rib style of panel, one manufacturer advises through the ribs whereas another advises through the flats ?

(Through a lifetime of working in technology fields, I have had numerous occasions to observe that some engineers are somewhat lacking in the knowledge of how their engineering actually works out in real life conditions. Therefore, I don't automatically assume that written instructions for a product necessarily represent the optimum method.)

 

[alchemysa]

One other point. If you ever have to walk around on that roof in the future its a lot safer if you can step on the screw heads for extra grip. (You cant do that if they're in the valley). And by the way I'd never use nails again. Hex head screws and a driver drill is the only way to go IMO. Apart from the ease, screws will never come out. All the old nailed roofs I've owned have had nails pulled out by the wind. And once they've been loosened they cant just be banged in again. I could be wrong but I doubt you'd even find a builder over here who would nail a roof.