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Milo (Milo)
Advanced Member
Username: Milo

Post Number: 45
Registered: 05-2009
Posted on Saturday, November 11, 2017 - 06:40 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Lee,
Not sure what point Bob is trying to make. I just put 1"x12" rough cut hemlock planks on my soon to be slated workshop roof without any worries. If the boards dont get wet they wont rot. Sure the "new growth" lumber today is not as hardy in the weather as some of the old growth but for a protected roof deck the point is moot. Besides, many surviving slate roofs on 100+ year old barns used planking that was available on site, in other words it was cut on the owners land. I am pretty sure some if not most of that wood was not of the "old growth" variety. I think you would be fine using what ever species that is rough cut locally...white pine, hemlock, oak, etc., etc.

MILO
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Lee (Lee)
New member
Username: Lee

Post Number: 2
Registered: 11-2017
Posted on Saturday, November 11, 2017 - 05:02 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

What is the solution to the New Growth problem then? I need to find 1" lumber to replace some sections of the roof deck.... where should I be looking for something that will last? One of the posts mentioned using 1" thick rough sawn hemlock....
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Bob_wewer (Bob_wewer)
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Username: Bob_wewer

Post Number: 8
Registered: 11-2013
Posted on Thursday, November 07, 2013 - 11:38 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Couple things: What is with all the tarpaper talk? Isn't this a roof you are talking about? Just do the job right. Underlayment used as a bandaide or diaper is wrong.

For solid planking we have the New Growth Wood dilemma. Most of anything felled post '86 or '87 is NGW that rots faster than it takes for the check to clear.

(Message edited by Bob_Wewer on November 07, 2013)
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Slate_man (Slate_man)
Senior Member
Username: Slate_man

Post Number: 569
Registered: 01-2007
Posted on Monday, February 22, 2010 - 07:15 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

I have though of working, up there. Never went any where with it, i am only a 1 1/2 from Montreal it would be nice. I have bid one job about 4 or 5 years ago.

I know that the company Heather and Little get alot of work up there and in the US, both copper and slate.
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Olde_mohawk_masonry__historic_restoration (Olde_mohawk_masonry__historic_restoration)
Senior Member
Username: Olde_mohawk_masonry__historic_restoration

Post Number: 128
Registered: 04-2007
Posted on Sunday, February 21, 2010 - 05:01 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Hey, Liam. Imagining you traveling to Alaska brought a thought to mind: Have you ever looked north of us? Just realized Montreal's 3 hours north and Quebec City another 1.5 hours, both with lots of old, slated structures. Ever had an inquiries from up that way?
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Slate_man (Slate_man)
Senior Member
Username: Slate_man

Post Number: 568
Registered: 01-2007
Posted on Sunday, February 21, 2010 - 04:41 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

I would need more info on the roof style and color to give you a real cost. We would be interested in doing the work, www.slateaffair.com .
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Old_school (Old_school)
Senior Member
Username: Old_school

Post Number: 404
Registered: 01-2009
Posted on Sunday, February 21, 2010 - 02:03 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Chris, nice looking house. With all of the copper flashings and curved roofs on it you will be getting about $20.00 a square foot into the roof. Just guessing, I would say between 160,000 and 200,000 dollars for a roof on that one. I don't know what it will cost for freight up there and I don't know how many slate roofers are in Alaska either.
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Chrisparker (Chrisparker)
New member
Username: Chrisparker

Post Number: 1
Registered: 02-2010
Posted on Saturday, February 20, 2010 - 11:58 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Hhttp://www.thehousedesigners.com/plan_details.asp?PlanNum=3429ello, I want to start building my house soon, and need a ballpark estimate for installing a high quality slate roof.http://www.thehousedesigners.com/plan_details.asp?PlanNum=3429 is the plans of the house. I live in alaska and want to know if slate will be problematic as well.
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Ted Timmer
Posted on Wednesday, September 22, 2004 - 10:58 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Joe, I was just recently asked to look at two jobs here in New York. One is 65 square of cedar shingles, the other 100 square of mottled green and purple. Same architect and same construction manager. I show up to the cedar house and see that most of the house is plywooded and I think I must be losing my mind. I have done a mountain of cedar roofs out in the Hamptons and not once saw a sheet of plywood, not to mention ice and water. The fact of the matter is, I never saw anyone else using it either and now I wonder if cedar has ice dams at all (seeing that it is such a good thermal break)? I have never witnessed an ice dam on a cedar roof. So I ask why plywood (instead of shingle lath) and the CM tells me that all of the eaves, valleys, hips, dormer cheeks (the whole house) needs a solid sheathing ofr ice and water barrier. I tell him I can't help him and that the cedar on that house probably won't last ten years. Good luck.

I go down the road to the slate job. Big big job. Plywood again. Everyone sitting there convinced that the house will have ice dams. I am too. There are 16 in 12 pitched roofs landing in the valleys of dormers that terminate with curved eaves that have a 4 in 12 pitch below the curve. Much of the house has this detail. I ask them if they are willing to trust a 5 million dollar home to a thin sheet of plastic and tar for the next 100 years. They look at me and wonder what I would do. That's it. On those curved eaves I am calling for 12 inch slates to get through the curve and I was thinking of a five inch headlap in those areas. The 4 in 12 pitched eave is what worries me. It's sticking 2'-8" out into the valley (yes it has a slight curve) and will act as a huge ice and snow guard for everything above the dormer. Any better ideas make this a lasting job? Oh, they don't want metal on the eaves.
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ted timmer
Posted on Wednesday, September 22, 2004 - 11:16 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

I wanted to add a little more to the above. The slate house I am talking about will also have a fairly serious soffit and ridge vent system along with R-30 ceilings. But from my experience with a very well vented "cold roof" with R-34 ceilings, ice is still a problem. The black slate will still generate enough heat from UV radiation to melt the snow on the coldest days and the water freezes solid at the eaves or in the gutters. I have not had any leakage in the eaves or in the house, the dams just aren't big enough to cause a problem. But it would not appear that "well vented roof" is the answer, though I do believe it is better than no ventilation (simply for the condensation in the insulation).
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Walter Musson
Posted on Thursday, September 23, 2004 - 06:30 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Have you considered using copper "pigtails" or other not too obtrusive snow guards on the field of the roof to capture the snowfall and let it gradually melt off?
In this way a lot of snow is melted above but not quickly and the melt has an opportunity to evaporate as it flows down the roof.
Without metal at the eaves the slate alone can't keep extensive ice dam back up out of the structure.
The last radical solution might be to install a loop of radiant heat tubing under the sheathing at the most problematic areas to keep ice from forming.
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admin
Posted on Thursday, September 23, 2004 - 10:26 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

I think that sometimes architects create problems in their designs and specifications that become inadvertantly adopted by the roofing contractors who end up installing the roof. My policy has been to simply not install slate roofs on decks that are plywood, or on roofs that are problematic due to design. If the owner or architect wants me to install the slate (or be the consultant on the job), they have to build it correctly (in my opinion) or find someone else to install the slate (or consult). That way, I can avoid becoming becoming the adoptive parent of a roof that I don't feel good about.

Having said that, I have installed two slate roofs over plywood decks, and one over particle board. These were not huge jobs (one side of a house with recycled slates, and two entire garage/additions with recycled slates) and there was no better alternative other than to install battens over the plywood, which we did not do because the owner didn't want to pay the extra money (we did install battens over the particle board, as I mentioned in an earlier thread on SIPs). I made it clear, before a contract was signed, that it was my policy to not install slate on plywood roofs and that I could not guarantee the long-term results. Since the slate was recycled and was only expected to last another 50 years, we went ahead and installed it over the existing decks. We always put *new* slate on board decks, however, and do the same with recycled slate 99% of the time.

Also, regarding IWS, I will install slate over it if the builder installs the IWS as long as it's limited to eaves, etc., and not all over the roof. I don't like IWS - it's slippery and creates a hazard on the roof as far as I'm concerned, and it serves no real purpose after the slate is installed.

So, despite my opinions about the correct way to design a slate roof, I have to be flexible in order to deal with situations as they arise. Better to put slate over 3/4" plywood than to put asphalt shingles over 1/2" plywood, but better to avoid plywood altogether.

My main point, however, is that you can pick and choose your slate jobs most of the time. If it smells bad, pass it on to someone else. There are plenty of guys who don't know any better.

Joe
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Ted Timmer
Posted on Thursday, September 23, 2004 - 04:04 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Having read your posts, I think I may indeed pass this one on. I spoke with the builder today and now they are willing to solid board sheath it, save for the the plywood they have put on at the eaves. (In my above post I should have said that they plan on plywooding the house and have only sheathed the first four feet of the roof at this point.) The issue is getting around the ice damning problem on the eaves and valleys.
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admin
Posted on Friday, September 24, 2004 - 11:10 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

We work on old houses with curved eaves and slate roofs. They don't seem to have any major ice dam problems. These are 90 year old houses with no IWS on board decks. They leak where the slates are broken (because someone walked on them there or something). Once repaired, the leaks stop. Proper sizing of the slate (not too long) and proper headlaps (4" or so) seem to suffice.
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slateworks
Posted on Sunday, September 26, 2004 - 10:38 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

You could install metal on the eaves,then install slate from the angle change-Or Install felt paper with slaters mastic- Or install Grace IWS 6'wide with a layer of 30# or heavier felt,install valleys with clips and a hemmed edge,solder all joints at angle change,tar edges(optional) of hem then install felt paper over edge of valley by several inches(If felt has been installed to protect roof ,cut felt paper so valleys can slide under existing felt or add new felt ect,)..-Do a dry layout with slate to figure out what lengths you will need you could start with 18" or 16"l slates then 14"-12"ect.layout slate so you have a double headlap the top of the first row goes under the bottom of 4th row by 2" to 4" and use the widest slate possible to help get as much sidelap as possible.Then double or triple your price for this area of work takes alot of time,we did not charge enough on the one we did. Snowgaurds above angle change could also help -use heavy snowgaurds,have seen decent snowgaurds bent backwards when used on long steep roofs.We installed a roof similiar to the one described above.The carpenters had installed 2 layers of IWS and 40# plus paper on eaves before the slate roof was installed(the roof was under felt for a year before slate was installed),so far no leaks on the eaves.Good luck.
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Ted Timmer
Posted on Monday, September 27, 2004 - 09:56 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

I got up on the roof again last week and really spent some time looking at the problem areas of the roof. I think that perhaps I was over worrying the eave detail a little. Yes, I think that the low pitch of the eaves could cause some problems, but I think the biggest problem is with water flowing horizontally across the slates as it comes through the valley. I plan on using bigger step flashing unless they want open valleys.

Next question: Is it at all common for the rows of slate in closed valleys to not line up with each other? On this job I would think it much easier to do closed valleys and not get involved with all of the detailed solder work needed to get an open valley through the curved design of the eave. Does that make sense? As well, they now want to pay me to "mock" up one dormer and make it permanent though the rest of the roof will not be sheathed or slated. If the valleys end up being closed, I don't see any way of making the rows line up. Of course this has got to be a five million dollar home and I am certain they want the valleys to look "right." I have looked at many many slate roofs any have not seen one where the rows are off. Perhaps they were designed a little better than this house, however.

Joe, are you looking for some work in November? :) Anyone?

One last gripe: this house is meant to look as if it were 200 hundred years old. But the indside is loaded with laminated veneer lumber as if beams didn't exist 200 years ago. Does anyone have any idea how long the glue on LVLs is expected to last? And why on earth would you build a house upon a foundation of glue joints?
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Michelle Waldron
Posted on Tuesday, September 20, 2005 - 12:43 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

I want to build a dormer on an existing tapered porch roof to divert the water so it doesnt dump on the stairs.
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Michelle
Posted on Tuesday, September 20, 2005 - 10:38 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Hi All!

I would appreciate it if someone would take notice of my message and help me out at your earliest convenience.

Sincerely,

Michelle
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admin
Posted on Tuesday, September 20, 2005 - 01:49 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Why don't you install rain spouting?

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