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Vcardenes (Vcardenes)
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Username: Vcardenes

Post Number: 4
Registered: 03-2015


Posted on Monday, April 13, 2015 - 03:36 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Hello John
Completely agree. I just want to add to the crimes perpetrated in the slate industry the defective manufacturing. How many times have you found that a good quality slate is bad trimmed, being very difficult (or impossible) to install it?.
Sometimes I have had the impression that the productive companies do not care about the real customer, the slaters, but just about selling more and more. Also, this can happen in any company from any country, if someone is going to say now that in his/her company the trimming is perfect, well..."who is without sin, cast the first stone"
Best regards.
Victor Cardenes
roofingslate.wordpress.com
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Old_school (Old_school)
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Username: Old_school

Post Number: 1105
Registered: 01-2009
Posted on Friday, April 10, 2015 - 09:14 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Victor, we agree then. I just resent it when people put "junk slate" on a roof and then watch it go to pieces in short order. that is criminal to me, as the labor is the same to install good stuff as it is for junk. It makes all of us look bad. thanks for the explanation. John Crookston aka Old School
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Vcardenes (Vcardenes)
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Username: Vcardenes

Post Number: 3
Registered: 03-2015


Posted on Friday, April 10, 2015 - 05:44 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Hello Old School
I understand your disagrement about my statement on slates. I think I didn't explain myself properly.
There is a disagrement on the terms "slate" and roofing slate", they do not mean the same.
From a geological point of view, a slate s.s. is a type of rock with very characteristics features. From a constructive/commercial point of view, a roofing slate can be not just a slate s.s., but many other rocks, such as phyllite, schist, cinerite, shale, and even sandstone. A roofing slate is any stone suitable for manufacturing plain, flat, thick tiles. Not all the slates s.s. can be used for roofing. In fact, roofing slate is one of the most select materials you can find in nature. That is the reason tehre are not so many outcrops of roofing slates, compared with other ornamental rocks like granite, marble, etc.
So what I mean when saying that there are no bad slates but bad uses is that if a slate is not suitable for roofing, it shouldn't be used for roofing and maybe for floorign instead. Also, a roofing slate with a high carbonate content shouldn't be used in an industrial environment, where the SO2 from the pollution will react with the carbonate to form gypsum -> the slate gets white and its mechanical performance diminish. Instead, that carbonate slate should be used in another environment, and surely will perform great.
So, I don't know if have explained myself...
Best regards.
Victor Cardenes
roofingslate.wordpress.com
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Old_school (Old_school)
Senior Member
Username: Old_school

Post Number: 1104
Registered: 01-2009
Posted on Thursday, April 09, 2015 - 09:54 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Vcardenes; Thank you for a very explicit explanation. I know the systems are different, but now I understand some of the parameters anyway. Here in Michigan anyway, we get a lot of cold days and very long winters; and the farther north in Michigan you go, the colder and the longer the winters get. In the far north of the Upper Peninsula, the joke is that they only have two seasons, WINTER, and the 4th of July. it is not really that bad.

I do disagree with you however on there not being any "bad" slates. I have worked on slate roofs well over 100 years old that are still holding their own against the elements and I have also worked on some of the softer Pennsylvania slates that are completely rotted after 40 years. They should never have been applied, at least in Michigan. I have also seen some real junk from Brazil and from China. I am sure they have some good rock over in those places, but I haven't seen much of it! I did apply some clear black slates that came from China about 25 years ago and they are still looking good. I also installed some very nice Spanish slates a few years ago. Good rock CAN come from anywhere in the world, as can BAD rock. Whom do you trust and what recourse do you have. If you don't know slate, you had better know your slate supplier. It also helps to have a "CHAIN" to "Yank" if need be.
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Vcardenes (Vcardenes)
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Username: Vcardenes

Post Number: 2
Registered: 03-2015


Posted on Thursday, April 09, 2015 - 04:41 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Hello
These two quarries are Spanish. In Europe, the tests used are according to EN 12326-2, which is under revision right now. The water absorption (WA) is calculated in a different way than in the ASTM C121, and so the values are different too. ASTM values usually are the half of EN values. This has some petrophysical implications that are not worth to discuss now, the point is that you shouldn't compare EN test with ASTM test, they are different. So the .63% WA for the slate is indeed a high value (the threesold for EN to perform the freeze-thaw cycle is .4%), then you should take into account the climatic data from your area and see how many days per year the temperature is below -5 °C. My advice is that under 30 days at that temperature the slate may work.
However, for me the best laboratory is Nature, I would look for slate roofs in your area and see how they have performed along the years.
And please remember, there are no bad slates, there are bad uses for the slates.
www.roofingslate.wordpress.com
Victor Cardenes
roofingslate.wordpress.com
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Joe (Joe)
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Username: Joe

Post Number: 852
Registered: 07-2006


Posted on Thursday, March 26, 2015 - 05:57 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Deborah - there is more info about these slates here: http://slateroofers.org/sources_new_slate.html#spain
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Old_school (Old_school)
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Username: Old_school

Post Number: 1098
Registered: 01-2009
Posted on Monday, March 23, 2015 - 09:43 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

I would assume those are Spanish slates. They have their own rating system over there. something about the EU. For the States, we talk about S-1 and S-2. Not sure what X-1 is. Did you ask the supplier or the person that gave you the estimate? There used to be a guy on this forum from ireland; Peter ws his name. haven't heard from him in a long time.
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Deborah (Deborah)
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Username: Deborah

Post Number: 1
Registered: 03-2015
Posted on Monday, March 23, 2015 - 08:15 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Hi there,
I've been given two slates to choose from..
The Del Carmen Premier..is this X1 ??
Or Del Carmen Celtas..
Any help on which one to go for??
I don't want a patchy roof so I'd go with the better one..
Thanks D
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Old_school (Old_school)
Senior Member
Username: Old_school

Post Number: 1088
Registered: 01-2009
Posted on Wednesday, December 24, 2014 - 05:18 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Englert, That is great information for everyone to use, but you have to work on your use of the English language..Then or than as it were; However, this is a forum on slate and it is hardly appropriate to be commenting on metal roofing here. With that in mind, you should go to a metal roof forum. Words of advice! Have a nice day. Don't hurry back.
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Englert123 (Englert123)
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Username: Englert123

Post Number: 1
Registered: 12-2014
Posted on Wednesday, December 24, 2014 - 06:29 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

There are different type of slates according to their quality, e.g. S1 and S2 type slates which can be differentiated on the basis water absorption etc.
However metal roof are better then the slate roofs as they have more resistance ability then the slate roofs.
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China_ad_slate (China_ad_slate)
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Username: China_ad_slate

Post Number: 7
Registered: 01-2011
Posted on Friday, April 01, 2011 - 01:39 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

hello, Carol, the main factors that decide the service life of roofing slate are Water absorption and acid resistance/weather resistance. Water absorption below 0.25% and acid resistance below 0.05mm, the service life can reach 75+ years, which belong to S1. Water absorption below 0.35% and acid resistance below 0.2mm can reach 40-75 years,which belongs to S2. Many people use S1 and S2 for roofing slate. For further detail, pls contact me nancy@adslate.net
Nancy Rao
Shanghai AD slate Co., Ltd
ASTM-S1/EN12326 T1 S1 A1
Roofing slate manufacturer.
WEB: www.cnslate.com
TEL: 86-21-61910796
FAX: 86-21-62199550
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Carol
Posted on Wednesday, November 19, 2003 - 01:41 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

I've just received the test results for roofing slate that I'm going to buy with the following characteristics:

Module of rupture - 7027 psi
Water absorption - .58%
Max depth of softening - .0011 inch

Would someone comment the quality of this slate?
Any advice is greatly appreciated.
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admin
Posted on Wednesday, November 19, 2003 - 05:16 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Here's some information from the Slate Roof Bible, 2nd edition:

The American Standards of Testing and Materials (ASTM), first organized in 1898, is a non-profit organization which writes standards for materials, products, systems and services. ASTM C406-00 provides standards for roofing slate, distinguishing between S1, S2 and S3 slate according to the criteria below. S1 slate rates a service life in excess of 75 years, S2 is rated for 40-75 years, and S3 is rated 20-40 years. In reality, hard slate (S1 slate) may last 400 years, while S2 (soft) slate may last considerably longer than 75 years.

The first column is the modulus of rupture; the second is the maximun absorption, and the third is the depth of softening in inches and (mm):

Grade S1-----9,000-----0.25-----0.002 (0.05)
Grade S2-----8,000-----0.35-----0.008 (0.20)
Grade S3-----7,000-----0.45-----0.014 (0.36)

For some additional information:

Average Absorption of Slate
After 48 Hours Immersion in Water

Monson, Maine: 0.05%
Vermont-New York:0.13%
Buckingham, VA: 0.06%
Eastern Pennsylvania
Bangor: 0.28%
Pen Argyl:0.30%
Hard Vein:0.16%
Wind Gap:0.38%
Slatington:0.29%

The top three varieties of roof slate have a much lower absorption factor and have also proven to last much longer on roofs than the slates listed below that have high absorption factors. This indicates that the less water a slate will absorb, the longer it will last.(Source: Bureau of Standards Journal of Research, Vol. 9, No. 3, p. 397, September 1932)
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Stephen Taran Jr
Posted on Saturday, November 22, 2003 - 10:29 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Carol.

They do not meet the S1 quality. If you are looking for S1 quality please contact me
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Regina Kwon
Posted on Wednesday, January 26, 2005 - 01:26 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

I would like to buy Spanish slate tile listed at 0.63% absorption. If I get this sealed will it be OK? It's for my kitchen. Also I had heard that it's the sealant that captures stains, is that ridiculous or only applicable to very nonabsorptive slate such as Maine or VErmont slate?
thanks!
regina
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admin
Posted on Wednesday, January 26, 2005 - 04:40 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

This is a roofing site, so it's unlikely you will get advice on kitchen remodeling.

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