# Gerard stone coat steel tiles



## MGP Roofing

I have nearly completed a re-roof of a 21 year old Gerard roof, which was replaced because the owner decided to completely change the look of the house; once we got under way it became obvious the roof didn't have much life left anyway. Leaks were beginning to occur from the corrosion along barges and valleys, there was quite a bit of rusting under the ridge caps too.
And, today, I undertook repairs to another older roof of the same product following re-siding of the upper level. During which I had the misfortune to put my foot through the roof!  That one has been re-surfaced at some time. Here's some pics of a few of the corroded tiles.


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## tinner666

Must not have heard of leaded copper for the flashing.


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## MGP Roofing

The flashings are made of the same stone coat steel as the tiles. That is standard around here. The worst rust we see is beneath lead flashings in most cases. Runoff from copper pipes or spouting is bad, too.


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## shazapple

What is the typical life span of these roofs? Looks like they are put down similar to tile. Are they as breakable?


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## AndyWRS

Wow, never seen that much rust on any stone coated job here in So Cal. I would imagine your location / climate could be part of the reason. What kind of life span are you getting from your Decra / Gerard in your neck of the woods anyway ?

21 years is not that old for a stone coated roof, is that typical there ?

Thanks again for the pics of the house in Mirangi bay, my father built it and i lived there as a wee lad  I miss NZ.

Cheers

Andy


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## MGP Roofing

AndyWRS said:


> Wow, never seen that much rust on any stone coated job here in So Cal. I would imagine your location / climate could be part of the reason. What kind of life span are you getting from your Decra / Gerard in your neck of the woods anyway ?
> 
> 21 years is not that old for a stone coated roof, is that typical there ?
> 
> Thanks again for the pics of the house in Mirangi bay, my father built it and i lived there as a wee lad  I miss NZ.
> 
> Cheers
> 
> Andy


We're getting 20-40 yrs out of them though it seems the newer ones are not as good as the older ones as far as durability goes (I read somewhere that the galvanising is half as thick as it used to be). It depends on the location, the 40yr old ones are a good hour drive away from the coast, but are at the end of their life.
I am noticing the same failure pattern with long run steel roofing, in one case a 15yr old addition was rusted clean through whereas the original 1950's roof was still good, just needed new fasteners!


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## WindowsonWash

Nice pics.

Do you think the oxidation and rust is directly tied to the salt spray and saline content in the air?


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## MGP Roofing

WindowsonWash said:


> Nice pics.
> 
> Do you think the oxidation and rust is directly tied to the salt spray and saline content in the air?


The salt spray/saline content of the air does contribute; my parents' house is 23yrs old with the same roof tiles still in relatively sound condition as best I can tell without taking it apart. They live about an hour from the coast so no salt in the air there. that long run steel addition/1950's original roof I mentioned in an earlier post is not far from them, so go figure. 
None of the rust on the roof that started this thread was visible until once the job was underway, so I really can't say whether or not my parents place will need a new roof in 5 years time, or if it will still be going strong in 10 years.


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