|Posted on Tuesday, June 12, 2001 - 10:42 am: ||
I can see the felt through some parts of my 1895 colonial. It is either deteriorating or has deteriorated. Should I be concerned about this if the roof does not leak? It is worse on the North side.
I can also see that certain (darker) colors of slate are weathering worse than the others (flaking) Should I replace these as preventative maintenance or wait until they really fall apart?
Lastly, the North facing roof is weathering far faster than the other sides. Is it possible to just replace that side and leave the others alone. Most slate roofers in the area want to redo the entire roof. This is not in the budget $$
Sound advice appreciated.
|Posted on Tuesday, June 12, 2001 - 06:30 pm: ||
I know Joe responded to your other question and I have a few thoughts about this particular dilemma:
- Is this a mixed color roof or does it just appear that way due to the deteriorated condition? In my opinion -- and it is difficult to be certain of anything without seeing the roof or viewing photos -- The "darker color slate" that is flaking is likely PA slate that is nearing the end. If they make up a small percentage of the overall roof, replacing them individually may be an option, but if the entire roof is PA, you may find that you are breaking 3 or 4 or more for every one you are trying to replace.
My experience is in buying, selling and recycling -- I am not a roofing contractor, but have installed 100 squares or so including my own home.
I have seen a lot of peeling, flaking chalky deteriorated PA and have had many clients through the years who started out trying to do spot repairs but once on the roof, found that what looked okay from the ground, was actually the consistency of wet crackers...
Then they end up tearing it all off. I'm surprised that the north side is worse. Usually, due to the freeze-thaw extremes, the south side gets it worse. Of course you may be in a temperate climate -- I'm in Vermont.
If you want to email me photos, I can tell you more.
|Posted on Wednesday, June 13, 2001 - 08:12 am: ||
This is a mixed color roof. Mostly greys and blue greys. The slate is probably 1/4-3/8" thick with the exposed corners cut. (don't know what style/cut this is called?)
I was incorrect about exposure. It is the southern side that is beat up and the northern that still looks good.
The roof doesnt leak as I can see the entire southern side since the third floor room is unfinished. I'd say there were about 6-12 darker ones which are obviously deteriorating at a faster rate than the others.
Just trying to do some preventative maintenance. I suspect the roof is coming to it's final years as the house is 108 years old.
I'll try to get some pictures.
|Posted on Wednesday, June 13, 2001 - 11:42 pm: ||
It is probably not wise to assume your roof is coming to it's end at 108 years. I recently stayed in a house built in 1785 with its original slate roof (in Scotland). I have worked on *many* slate roofs over 108 years olds that still had many decades of life in them.
Felt paper under the slate at 108 years of age is inconsequential. It serves no useful purpose and you should not be concerned with it.
The south side always goes bad first in the northern hemisphere. Yes, you can replace just one side.
If you have a multi colored slate roof and the black ones are going bad, just replace them. It's possible that they're repair slates anyway, but, if not, they can easily be replaced.
|Posted on Thursday, May 30, 2002 - 08:28 am: ||
IS THERE A WAY TO "TEST" OLD ROOFING SLADE TO DETERMINE IF IT IS PRACTICAL TO REUSE? I HAVE A CUSTOMER THAT WANTS TO SEND SOME SAMPLES TO A TESTING LAB!
|Posted on Tuesday, June 04, 2002 - 09:23 pm: ||
Yes- an informed/experienced slater could/should perform a variety of visual/touch/resonance tests to each and every slate that passes through his hands- he can(if properly experienced) make certain comments/critiques on a batch of slate w/o having to intensely inspect each one- say if they're still on a roof to be removed/relaid/? The approach your customer is taking, in my opinion, is tangental to real slating and probably should involve the input of a statistician to indicate how many slates %-wise to test to give a probability? Further, what would said lab test for? One needs to do a little steering here to get relevancy- I could imagine a figure like 15% would need to be "tested" but ask the "experts"- remember, few individuals are adequately "vetted" to give high-quality responses to questions on slate and slating. Slates are a collection of averages rather than a uniform product- some of a batch will "never" wear out, others should never have left the quarry.
|Posted on Thursday, June 13, 2002 - 05:29 pm: ||
Balance the slate on your fingertips
Inspect it visually for suitability as roofing
- (I can elaborate on "suitability" if you wish)
If it has visible defects, discard (if severe) or set aside for cutting into a smaller size for reuse on the roof or perhaps for Arts & Crafts.
If it passes the visual test, tap it lightly but firmly with a hammer.
If it is "dead" sounding then discard.
If it "rattles" look for the source of the rattle. It may be a hidden crack, or perhaps only "whiskers" -- some loose layers on a corner that will not necessarily render it unfit.
If it rings "like a bell" or a piece of wedgewood china, then you have a winner. Tuck it away for future use and make a mental "chi-ching" 'cause it's money in the bank.
Hope this helps,
|Posted on Tuesday, February 03, 2004 - 04:24 pm: ||
I want to thank you guys (and the Good Lord) for this website. My sixty year old house started to leak, and my wife and I were ready to sign a contract to replace it with plastic. Now I realize we don't have to do that, and we will have a slate specialist just repair what needs to be repaired and not re-do the whole roof. thanks guys. ps just ordered the bible on amazon
|Posted on Tuesday, February 03, 2004 - 07:46 pm: ||
Regarding slate testing labs, we now have some listed on the National Slate Association web site at http://www.slateassociation.org/testing_labs.html
|Posted on Saturday, April 30, 2005 - 11:31 pm: ||
i'm intrested to find out what a slate roof weighs per square if anyone can help it would be greatly apreciated
|Posted on Saturday, April 30, 2005 - 11:56 pm: ||
Depends on the thickness of the slate. Standard thickness (3/16" to 1/4") weighs roughly 600 to 700 pounds per square.
|Posted on Friday, May 27, 2005 - 05:09 pm: ||
My wife and I just bought an 1880's ish old victorian with a mansard roof.
The original house has been added on to a couple of times. We believe that the first addition meant removal of the slate and then shifting it to fill in the front of the house because the remainder of the addition has been covered with pressed tin - painted.
The previous owner has painted the slate roof several times (we believe in order to match the tin that needed to be painted).
The slate also has quite a bit of mold growing on the north side.
It is nearly impossible to tell how much damage has been caused (if any at all).
What do we need to do?
Scrap off the paint?
Leave it and clean it?
Any suggestions would be helpful because I am unable to find anything regarding painted slate in any websites.
|Posted on Friday, May 27, 2005 - 07:21 pm: ||
Paint sticks to slate pretty well - so you'd have a hard time scraping it off. I think you have to live with it. You can scrape off the moss, however.