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Lazeyjack (Lazeyjack)
Senior Member
Username: Lazeyjack

Post Number: 70
Registered: 04-2012
Posted on Saturday, August 11, 2012 - 04:52 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Fine Joe thanks
best rgds
Stuart
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Joe (Joe)
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Username: Joe

Post Number: 707
Registered: 07-2006
Posted on Friday, August 10, 2012 - 10:24 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Here are some slate roofing books:

http://josephjenkins.com/store/books/
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Lazeyjack (Lazeyjack)
Senior Member
Username: Lazeyjack

Post Number: 69
Registered: 04-2012
Posted on Friday, August 10, 2012 - 05:38 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Joseph
Kinda like a book that covers the broad spectrum
So
We have a roof could be plain or complex, with skylights and even steel chimney pipes
So book covering flashing and ridges
I dunno just a broad HOW TO BOOK?>
best rgds
Stuart
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Old_school (Old_school)
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Username: Old_school

Post Number: 862
Registered: 01-2009
Posted on Thursday, August 09, 2012 - 11:07 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Joe, I think he wants to go to a "revival" and he needs a "bible" that talks about slate. I would think that a good name for that book would be "The Slate Roof bible" Is that name taken?
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Joe (Joe)
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Username: Joe

Post Number: 703
Registered: 07-2006
Posted on Thursday, August 09, 2012 - 10:49 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Stuart - what book are you referring to?
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Marcoattici (Marcoattici)
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Username: Marcoattici

Post Number: 11
Registered: 06-2012
Posted on Thursday, August 09, 2012 - 06:04 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

we have used veltisun of Monier company... we don't know if available also there
http://www.nbmcw.com/products/roofing-cladding-peb/roofing-cladding/17242-monier s-perfect-roofing-system.html
or
http://www.monier.in/fileadmin/bu-files/in/pdf_files/Newsletter.pdf
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Spextheslater (Spextheslater)
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Username: Spextheslater

Post Number: 5
Registered: 05-2012
Posted on Wednesday, August 08, 2012 - 06:24 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Frank, We use Tyvek Supro as a breathable underlay here on fully sarking (boarded) roofs on re-slates or new builds. Slate straight on top no battens. Altho we wouldnt sheet it with ply...
The spec is here
http://construction.tyvek.co.uk/Tyvek_Construction/en_GB/products/roofing/index. html
You want the one with the sticky laps :)
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Scottishslater (Scottishslater)
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Username: Scottishslater

Post Number: 136
Registered: 01-2012
Posted on Wednesday, August 08, 2012 - 01:31 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

yes would be battens lazy
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Frank (Frank)
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Username: Frank

Post Number: 4
Registered: 08-2012
Posted on Wednesday, August 08, 2012 - 10:08 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Gentlemen, Thank you for suggestions...

Joe : yes, furring strips was one of my ideas, but the decision has been made now to go with PS1 (structural), Exterior grade 3/4" plywood for a base.

Old School : yes, raising dormer tops would keep our line, but the added expense is prohibitive in this case, since the project is already over-budget...

QUESTION : Can anyone suggest a sort of *thin* underlayment that could be nailed through, with slate directly on top, for even a modest r-value increase? (There is an opportunity with another roof to insert something, but a lot of the new materials seem inappropriate for use in a slate roof system).

Best regards,
Frank
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Lazeyjack (Lazeyjack)
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Username: Lazeyjack

Post Number: 68
Registered: 04-2012
Posted on Tuesday, August 07, 2012 - 07:47 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

ah I see, now,, i think in UK they would be termed, battens
best rgds
Stuart
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Old_school (Old_school)
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Username: Old_school

Post Number: 860
Registered: 01-2009
Posted on Tuesday, August 07, 2012 - 05:01 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Stuart, Firring strips are the equivalent of "Sarking" as you would call it, nailed to the rafters and spaced to accept the slates. We are certainly one people divided by a common language!
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Lazeyjack (Lazeyjack)
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Username: Lazeyjack

Post Number: 66
Registered: 04-2012
Posted on Tuesday, August 07, 2012 - 03:57 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Wot are furring strips
Joseph where do I buy this talked about book?
best rgds
Stuart
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Old_school (Old_school)
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Username: Old_school

Post Number: 858
Registered: 01-2009
Posted on Sunday, August 05, 2012 - 02:53 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

If you want to keep the "look" just raise the roofs of the dormers so that everything is proportional.
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Joe (Joe)
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Username: Joe

Post Number: 702
Registered: 07-2006
Posted on Sunday, August 05, 2012 - 12:22 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

What size slates? Can you run furring strips horizontally over the foam and nail the slates to the furring strips? If you're using 22' slates (for example), you would need furring strips horizontally on 9.5 inch centers.
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Frank (Frank)
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Username: Frank

Post Number: 3
Registered: 08-2012
Posted on Friday, August 03, 2012 - 11:45 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Ernest Flagg Ridge Dormer
The Beaux-Arts architect Ernest Flagg featured ridge dormers on most of his stone house designs, for air circulation + light.

Old School,
I have no doubt your suggestion would work -- it was my first thought & if money & increased height on a National Historical Landmark house were not issues, it's clearly the way to go. But money is limited & the cost is above what was contracted....

May we switch to the other questions I had posted :

2) Is our current plan adequate, if not ideal?

3) If we removed the foam board, is there any type of thin underlayment material for the slate that would serve to increase the r-value?

Many thanks,
Frank
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John_chan (John_chan)
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Username: John_chan

Post Number: 111
Registered: 08-2006
Posted on Friday, August 03, 2012 - 11:39 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Hi Frank,

You could probably tear out the insulation and put an insulated deck on before putting the slate on. Try calling our Indianapolis office at 317-925-8453 or request an estimate at www.durableslate.com.

John
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Old_school (Old_school)
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Username: Old_school

Post Number: 856
Registered: 01-2009
Posted on Thursday, August 02, 2012 - 10:03 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Frank, what is a "Ridge dormer?" If you do what I suggest, it will work, but you will have to raise the siding on the sides of the dormers to allow for the extra height. I am sure they did it when they installed the 2" of insulation before too. If everything was raised up 5 inches to allow for the sir space it would all look the same. You would probably have a 'stacked fascia" detail to hide the extra height. It takes a lot of time and money to do it, but it will solve your problem. good luck with that one.
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Frank (Frank)
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Username: Frank

Post Number: 2
Registered: 08-2012
Posted on Thursday, August 02, 2012 - 08:41 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Old School,

If I understand you correctly, that would raise the roof 3" (2xs + 1" board). We don't have enough wiggle room on this house because (a) we are already 2" higher than the original ridge (adding 3 more inches would take it to 5" higher), (b) there are 6 dormer windows that can't accept this extra height, and finally (c) one of the architect's signatures was dormer ridge vents -- at the ridge line -- we already have the problem of 2" higher; at 5" higher, they are no longer ridge dormers ;-/

But thanks for the speedy feedback,
Frank
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Old_school (Old_school)
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Username: Old_school

Post Number: 854
Registered: 01-2009
Posted on Thursday, August 02, 2012 - 07:31 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Frank, why not install some 2 x 4 sleepers on the flat over the existing rafters, over the 2" insulation. It is rigid enough so that it won't compress, and then you can install solid 1" boards over the sleepers for the slate to attach to. If you vent the bottom, (it will extend over the existing a few inches) perhaps you could install some Airvent II ridge vent at the peak and install some of Joe's copper ridge roll over that. It would work and eliminate a lot of other problems at the same time.

If you have any specific questions about this you can always give me a call!
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Frank (Frank)
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Username: Frank

Post Number: 1
Registered: 08-2012
Posted on Thursday, August 02, 2012 - 06:55 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

NEED ADVICE : HISTORIC HOUSE SLATE ROOF PROBLEM

Our historic house originally had a slate roof. Previous owners removed slate & we are taking it back to slate. But we encountered an unexpected problem & can't come up with a good solution : the previous owners put 2" foam board directly under asphalt shingles (that's right, no decking).

Specifics : roof is over interior cathedral ceiling. Existing roof structure = interior plaster, interior t&g ceiling, 1928 shredded paper insulation (sandwiched between felt backers), a wonderful 1 3/4" T&G exterior deck, 2" Dow styrofoam insulation (blue board), felt, asphalt shingles.

Because we need the insulation, our current plan is to keep the 2" foam board, sheath over with PS1 plywood screwed through to solid wood deck, felt & slate, but I am not happy about this.

So my questions are :
1) Is there a better way to slate over existing insulation?
2) Is our current plan adequate, if not ideal?
3) If we removed the foam board, is there any type of underlayment material that could serve as insulation (increase the r-value)?

Any thoughts would be greatly appreciated,
Frank
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Pauly_d (Pauly_d)
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Username: Pauly_d

Post Number: 1
Registered: 09-2010
Posted on Thursday, September 30, 2010 - 10:09 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

1916 bungalow with vermont slate in central mass. no leaks in 8 years deck is 3/4 t&g
hipped all around
no vents soffit or ridge
t&g floor with loose insulation
walkup attic staircase 6'x6'
huge heat loss
would like to insulate roof deck and reclaim area as bath & bed
so far two opts
closed cell to the depth of the rafters 6"
loose cellouse packed bay with 1" foam board attached on rafter face
please pros and cons
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Slate_man (Slate_man)
Senior Member
Username: Slate_man

Post Number: 484
Registered: 01-2007
Posted on Thursday, September 24, 2009 - 06:02 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Terry you should have venting under the slate, don't install the foam rigth up to the slate. The more the slate can vent the long it will late. It would be best to leave the rafter open if you can, see that you can only vent with vent fans, which will not vent each rafter bay and under the slate if you install foam.
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Terryg (Terryg)
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Username: Terryg

Post Number: 2
Registered: 09-2009
Posted on Wednesday, September 23, 2009 - 05:14 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Hi Braymer

No, I would never allow them to spray over wet insulation. The roof has to roof top ventilation fans. The shape of the roof is like a hip with parapet walls in the middle with a flat roof. The exterior angled walls are slate. I would love to be able to have them just insulate above the drop ceiling. The volume of wasted space that they are conditioning is silly. I have seen fiberglass installed on top of drop ceilings before but they never seem to be done very well because of all the obstructions to cut around. My thought was if they really wanted to still condition all that space then remove the fiberglass and have a closed cell spray foam applied that would act as a vapor barrier and a high level of insulation. I am assuming because I can't see it that the slate was installed on skip sheathing. If this is true they couldn't spray right on that because foam might come out from under slates or lift them slightly. Not sure what to do exactly that would be cost effective.
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Braymer (Braymer)
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Username: Braymer

Post Number: 132
Registered: 09-2008
Posted on Wednesday, September 23, 2009 - 01:22 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Get that insulation out of the rafters, unless there is obvious ventilation and air space between the insulation and roof deck. Are you also absolutelly sure that it is not a leak that let water in and is trapped behind the plastic??
Poly works as a vapor barrier well enough, but if the insulation and ventilation is inadequate, the poly will do its job by keeping the moisture in that space, which is not what you want..
That roof should be cold in cold weather, keep the insulation as far as you can get it away from the roof if ventilation is NOt an option. Heck , even insulating closer to that drop ceiling and leaving a huge space betw. that and the roof would help. If it is not a leak, get that rotten wet stuff out of there and insulate it correctly.. If they spray foam over that wet stuff (sealing in the rotten moisture), that would not be good, make them remove the wet stuff first...
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Terryg (Terryg)
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Username: Terryg

Post Number: 1
Registered: 09-2009
Posted on Wednesday, September 23, 2009 - 12:43 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

One of my clients has a slate roof that is insulated in the rafters and has poly on the underside. It is not sealed and is torn in areas. I see mold growing on the inside of the plastic. The design of the building is a library that has drop ceilings. They have huge volumes of space between the drop ceiling and the insulated roof. Obviously the poly is not working. I have had insulation contractors suggest that they spray foam over the fiberglass completely to prevent air passing through the roof. Would this cause any problems down the road if we took this appraoch to tring to make the building more energy effecient?

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