| Author | Message | ||
     Paul_j (Paul_j) New member Username: Paul_j Post Number: 8 Registered: 01-2017 |
Thank you John | ||
| Old_school (Old_school) Senior Member Username: Old_school Post Number: 1215 Registered: 01-2009 |
So the existing roof is installed directly over OSB then? What is the "New decking? If you are going to have insulation beneath it, you may want to consider counter battens on it. Use the 24 inch slates, but install some of the synthetic self adhereed underlayment beneath it directly over the nail base. That will give you a surace like the titanium underlayment with a sealer beneath it, and then you would have vertical battens nailed down through it and horizontal battens to fasten the slates to, It would breath, and the slates would not be in contact with anything but the wood. Perhaps you could call Bob Williams at Newmont Slate and check out his Quik Slate fastening system. It uses hooks instead of nails and that would leave the slates held in place, but loose at the same time. You would be assured that it would not leak, as this is a lot better system than what you have currently, and that system doesn't leak as it is. Give me a call if you have any questions. 269-806-1266 or call Bob. Good luck. John Crookston Old School | ||
| Paul_j (Paul_j) New member Username: Paul_j Post Number: 7 Registered: 01-2017 |
Old School - thank you for the response. The existing roof is not leaking. It sits on non-ventilated nailbase insulation on a glulam deck. The quarries in Vermont basically will not provide a 26" slate. (They will provide it but indicate it could be more than a year before they would be able to provide it). | ||
| Old_school (Old_school) Senior Member Username: Old_school Post Number: 1214 Registered: 01-2009 |
Paul, Normally the slates are cut in 2 inch increments. 20's 22's 24's etc. The bigger longer slates tend to also be thicker. If you got 26 inch slates, that would give you a 4 inch head lap and that should be fine. You could also install some Ice and water shield along the bottom, but just make sure you install some type of slip sheet or felt or one of the synthetic underlaymnts over the top of it. It makes it much easier to do the repairs without the backs of the slates sticking to the underlayment. Just a question, is it leaking with the 2 inch headlap? What type of insulation is being installed beneath the roof? Is it ventilated? What is the deck type? There are a lot of questions involved with any type of roof, and especially when you are tying into a slate roof. Who is doing the specing on the roof? | ||
| Paul_j (Paul_j) New member Username: Paul_j Post Number: 6 Registered: 01-2017 |
The contractor is ready to order the slates. Turns out that the existing slates are 24" long with 11" exposure and only 2" headlap. Drawings/specs call to match the exposure and provide length as required to provide 3" headlap in field (25") and 5" headlap (27") within 3' of eave (for ice damming). Contractor is getting resistance from supplier on lengths. Is it possible to get these lengths? Contractor indicates the only solution is remove all existing slates and reinstall with a 10.5" exposure to get 3" headlap. This would be a hefty change order and still would not provide 5" headlap at eaves. Any thoughts? | ||
| Paul_j (Paul_j) New member Username: Paul_j Post Number: 5 Registered: 01-2017 |
Thank you Chris and John. | ||
| John_chan (John_chan) Senior Member Username: John_chan Post Number: 183 Registered: 08-2006 |
Yes, Chris is correct. It's a Vermont Semi-Weathering Gray or Semi-Weathering Gray Green. By the way, if you need an installer, we have worked in NJ from our Baltimore office. John Chan The Durable Slate Co. 1750 Union Baltimore, MD 21211 410-235-7500 www.durableslate.com jchan@durableslate.com | ||
| North_country_slate (North_country_slate) New member Username: North_country_slate Post Number: 2 Registered: 11-2016 |
Hi Paul, The color appears to be Semi-Weathering VT Gray. I've attached a photo of a custom home project we supplied slate for years ago with this color so you can compare with the existing slate from your project. The coloring characteristics seem very familiar in regards to the battleship gray and brown/tan weathering tones. Regards, Chris Large North Country Slate  | ||
| Paul_j (Paul_j) New member Username: Paul_j Post Number: 4 Registered: 01-2017 |
Thank you John. | ||
| John_chan (John_chan) Senior Member Username: John_chan Post Number: 180 Registered: 08-2006 |
Nice roof. It looks like Vermont Gray Green with maybe some Purples blended in. John (Old School) is correct about getting some extra slates that are longer for the first couple rows. | ||
| Paul_j (Paul_j) New member Username: Paul_j Post Number: 3 Registered: 01-2017 |
Thank you again. I will post more photos when I get back to the site in a week or so. | ||
| Old_school (Old_school) Senior Member Username: Old_school Post Number: 1198 Registered: 01-2009 |
Paul, The texture of the close-up photo certainly looks like it could be Vermont. If there is a slight tinge of red in it, it probably is because you don't get red from anywhere else. At 12/12, a 3 inch head-lap is preferred, but if it is slightly less it is not going to hurt anything. What I said about increasing the head-lap along the bottom is still a good suggestion. If the existing slates are 20 inches, get enough 22 inchers for the first 4 or 5 courses and it will do the same thing. A couple more pictures of the whole church with a "zoom" lens would be nice. Also, a closeup in the sunlight. would be great. The slates are laid nice and straight so if there is any variation in the head lap it is not bad. It is also hard to tell if they are random or laid half and whole. A zoom picture would tell us that. | ||
| Paul_j (Paul_j) New member Username: Paul_j Post Number: 2 Registered: 01-2017 |
Thank you Old School. Some photos of the existing are attached. Unfortunately, the eave shot was set up on the side of the roof that was in shade. The owner believes it is a Vermont gray, but I see light gray, dark grey and pale red in the South photo.    | ||
| Old_school (Old_school) Senior Member Username: Old_school Post Number: 1197 Registered: 01-2009 |
Paul, post picture or two. As far as the increase headlap, just order the slates 2" longer and install them at the same exposure as the existing. As far as the "weaving", just take out the first 1 or 2 slates on the existing roof and then install the slates o n the new section. It will be seamless. The reason for posting the p9icture is that we can identify the existing slates. You will want to get the same thing and they will be a perfect blend. Good luck with it. | ||
| Paul_j (Paul_j) New member Username: Paul_j Post Number: 1 Registered: 01-2017 |
I am designing an addition to a church with an existing slate roof with 12:12 gable. The addition will match the existing gable (same width, pitch, and height). I am not certain how to handle this butt joint between new and existing. Is it possible to weave the shingles to the existing or is there a typical metal flashing detail that should be used. As a possible further complication, I am skeptical that the existing roof has a proper 3" headlap. I also would like to follow recommendations I have read for an increased 5" headlap for the first 3' of the eave. Any thoughts are much appreciated. |
