Does this roofing material look okay?

[Leejosepho]

This may void a warrenty and also by doing that you are changing the MFG.s install procedure...unless it is in the install instructions.

Sure, I understand. The instructions mention use of butyl caulking along with the foam closure strips as well as under the heads of any screws used to plug mis-drilled holes ... but I am only assuming compatability between butyl and the nails' neoprene washers.

A related factor here is that this new roof is only 9' long from eve to peak, and the Ondura shets cover 6 feet. So, we will only have a total of four rows of nails (4" o.c.) about 25 feet long ...

. . . . . . . . . . . ridge cap
... . ... . ... . ... lap joints
. ... . ... . ... .
..................... roof edge

... or something like that.

 

[Old Dog]

roof install...

Sure, I understand. The instructions mention use of butyl caulking along with the foam closure strips as well as under the heads of any screws used to plug mis-drilled holes ... but I am only assuming compatability between butyl and the nails' neoprene washers.

A related factor here is that this new roof is only 9' long from eve to peak, and the Ondura shets cover 6 feet. So, we will only have a total of four rows of nails (4" o.c.) about 25 feet long ...

. . . . . . . . . . . ridge cap
... . ... . ... . ... lap joints
. ... . ... . ... .
..................... roof edge

... or something like that.

Correct installation is the key to this roof not leaking...Here in Hawaii fastners with neoprene washers is all you see for the most part.My house has a metal roof with these fastners and never had a leak.(annual rainfall 140"s)
It's interesting how climate plays a big part in the decision to use or not use certain materials.No one uses shingles here because the roofs turn black within a year from all the rain.Metal roofs are the norm here.
BTW, you haven't lived until you've walked on a metal roof over purlins with trusses on 4' centers! Alot of houses built like that here...

 

[Sponsor]

 

[Leejosepho]

BTW, you haven't lived until you've walked on a metal roof over purlins with trusses on 4' centers! Alot of houses built like that here...

Whew! That is even difficult to imagine. Few people have 4' strides, and to have to do that while stepping sideways on a pitched roof (unless the perlins are really strong) would certainly be quite a challenge!

 

[Leejosepho]

... it is heavily reliant on a good install to prevent leaks.

One thing we have done here is to add a second layer of 7/16" OSB sheathing. A single layer had a lot of flex, leaving me concerned about nails possibly working loose and leaking where they go through the roofing material.

 

[GregO]

onduline

I've seen "20-year" shingles last 40 years. It all depends on the elements (e.g., shade, sun, temperature, rainfall).

I'd be surprised if you got 20 years of useful life out of this material because it will break down. You will likely hit a couple "air pockets" as well when installing, so your nail or screw will not grab anything but a plywood seam. Those holes of course then need to be filled and somewhat maintained.

No good quality roof installation should require liquid ashphalt or liberal amounts of roof cement (contrary to what some TV "diy"ers have stated)! Exposed nails and screws can work fine (as illustrated by the Hawaii example), but the more exposed anchors, the more potential for problems. I've seen dinner-plate-sized leaks come from a single nail that had popped up halfway out (in the middle of the roof), and that was on a 45-degree sloped (capecod) roof!

I can't fight the bad visions of expansion/contraction/movement over the years loosening up this "system" even further.

My 0.25 cents (inflation) Greg

 

[Leejosepho]

I've seen "20-year" shingles last 40 years. It all depends on the elements (e.g., shade, sun, temperature, rainfall).

I'd be surprised if you got 20 years of useful life out of this material because it will break down.

Like shingles, it is asphalt, but heavier, and it will likely be recoated at least every ten years. So, it is not difficult for me to believe it at least could outlast those shingles. We might very well end up wishing we had never heard of this stuff, but at least we will eventually know for sure!

You will likely hit a couple "air pockets" as well when installing, so your nail or screw will not grab anything but a plywood seam. Those holes of course then need to be filled and somewhat maintained.

We should not have that problem. We have already put nailer blocks in behind the facia board to catch the bottom row of nails, we might still add under-decking nailer blocks at the overlaps, our first layer of decking has nailers under the seams and our two layers of decking are crossed.

I can't fight the bad visions of expansion/contraction/movement over the years loosening up this "system" even further.

I understand ... and we will certainly find out one way or the other!

 

[Leejosepho]

Keep us informed of how it goes.

Well, no Ondura, and I do thank everyone for all the comments. Getting everything ordered last week at the box store was quite an ordeal, but I ultimately got a complete refund after rejecting everything mostly because of some damage caused by rough handling. For $600.00, I was hoping the panels would at least be stacked straight when I went to pick them up!

So, now back to searching for something other than 3-tab shingles ...

 

[Livin4Real]

Sorry to hear that, I was looking forward to info on a new system. As far as shingles go, look around at different dimensional shingles. They're heavier, much better looking than regular shingles, last a long time.

 

[Leejosepho]

You will likely hit a couple "air pockets" as well when installing, so your nail or screw will not grab anything but a plywood seam ...

Well, you were correct about that, and even though we had two layers of 7/16" OSB! But, we ended up using some asphalt shingles rather than the corrugated roofing material, so the occasional nail that went in a little too easily is not such a big deal.