|Posted on Sunday, January 19, 2003 - 08:01 pm: ||
The Slate Roof Bible discusses "open lath"
sheathing, where there gaps of 6" or so between
sheathing boards, and "closed lath" systems
with no gaps between boards, and recommends the
latter for a number of reasons.
However, our house and barn both have "open lath"
roofs, and I have discovered that they have one
significant advantage: You can reach the slates
from inside the building.
This means that if a slate or two breaks and
opens up a hole in the roof, you can stop the
leak by slipping in a piece of roofing felt from
the inside. It may take a few tries to cut out
the right sized piece and maneuver it into place,
but once it's there (and fastened with duct tape
or brads to a convenient lath) it makes a very
effective temporary fix and IMHO is much better
than having to put a bucket under the spot.
Furthermore, you can do this in conditions of
pouring rain, darkness, sub-zero temperatures
or when you otherwise just don't feel like
putting up ladders and climbing on the roof.
You still have to fix it right later, but it
buys you a lot of time.
Does anyone else agree that this is an argument
for open-lath sheathing when re-roofing?
|Posted on Sunday, January 19, 2003 - 09:01 pm: ||
My 1815 farmhouse has open lath sheathing and I did exactly what you described a week after we moved in. A missing slate allowed water to leak in between the two beneath it. My temporary fix was the insertion of a piece of sheet lead used for lead shower pans. It stopped the water for two months until I could get the slate replaced.
However, when I re-sheath my garage for installation of salvaged Peach Bottom slate, I am going to go with "closed lath" rough sawn 1" lumber. Yes, the open lath allows the easy temporary repair from inside, but I feel that the closed lath with 30lb felt will likely prevent water penetration if/when a slate fails. I think the positives outweigh the loss of the inside access.
Jim K in PA
|Posted on Monday, January 20, 2003 - 03:40 pm: ||
I agree that a solid board deck is much superior to a skip sheathed one,except for the inside access issue.The act of nailing on the slates is easier and less spongy with full decking,plus the advantage of using 30 lb. felt as Jim points out.
|Posted on Monday, January 20, 2003 - 09:32 pm: ||
Thanks for the replies. I have one other
related question: when re-sheathing an open-lath
roof, is it necessary to tear off all the old
boards, or could you just nail new ones in the
I realize the surface wouldn't be quite as
even if you left the old boards on, but I was
just wondering if anyone's had any success
with this approach.
|Posted on Monday, August 09, 2004 - 08:29 pm: ||
i am going to purchase a house that has cedar
shake and two ashphalt roofs. it was built in 1900.
under the cedar shake is "barn board". it is the
board that has large spaces in between the pieces. i
was considering tearing off the roofs and putting on
slate. my question is, would i have to add boards to
make the decking solid, or could you slate with the
spaces, similar to how they ran the shake shingle.
your site is helpful and i will be buying the bible.
thanks for any help.
|Posted on Saturday, August 14, 2004 - 11:40 am: ||
The last lath roof we slated we added 1x4 rough-sawn hemlock boards between the existing oak lath.It was a barn and a photo is shown at http://www.jenkinsslate.com/photos_barns.html.
The slate roof we installed before that on a residence with an old oak lath roof required that we nail 1x10 rough-sawn hemlock boards right on top of the lath prior to slating, using 16 penny nails. There is a photo of this one too at http://www.jenkinsslate.com/photos_residences.htm
(scroll down to Volant, PA roof).