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gert
05-02-2006, 12:11 PM
I am about to finish re-roofing my shop with medium split resawns X 24" (treated) 8" exposure; should I apply a zink strip under the ridge cap? Or would this affect the treatment, or is it redundant?

Scubastud
05-02-2006, 12:20 PM
We have much better materials than wood to put on a roof. I suggest steel. I bet your insurance company would as well.

Popeye
05-02-2006, 12:22 PM
cedar shinkles are nice , steel is ok for a factory

Mrleft8
05-02-2006, 02:27 PM
Why would you want to put a zinc strip under your cap board?

gert
05-02-2006, 02:31 PM
These are treated split "shakes", 50 year expected life, besides, nearly finished means "They is on" . And yes there are better roofing materials, I'm not convinced steel is one of them (was considered) it's not like we get a lot of snow here

Bob Smalser
05-02-2006, 02:33 PM
By all means add the zinc as it'll kill roof moss without hurting the cedar or the fire retardant polymer it was treated with...but I'm afraid the picric acid in the cedar will eat it up in a few years, so make it so's it can be replaced.

Furry Buffalo
05-02-2006, 02:36 PM
Picric acid? Dont they make detonators out of that?

Mrleft8
05-02-2006, 02:40 PM
Zinc kills roof moss? I'm wondering why the zinc in galvaized roofing nails doesn't kill roof moss..... I just noticed a nice (not) crop of roof moss on my northern exposure. Fiberglass/asphalt 3 tabs.... Any way to kill this without killing the roof, and all the plants on the drip line?

RichKrough
05-02-2006, 03:02 PM
Zinc kills roof moss? I'm wondering why the zinc in galvaized roofing nails doesn't kill roof moss..... I just noticed a nice (not) crop of roof moss on my northern exposure. Fiberglass/asphalt 3 tabs.... Any way to kill this without killing the roof, and all the plants on the drip line?

The old standby for killing moss on roofs and masonry has been a mix of 1 part Clorox to 8 parts water in a pump sprayer. don't use a lot at once if you have a well nearby. White Vinegar may work also

Scubastud
05-02-2006, 03:39 PM
The old standby for killing moss on roofs and masonry has been a mix of 1 part Clorox to 8 parts water in a pump sprayer. don't use a lot at once if you have a well nearby.

If you have to worry about run off from a pump srayer containating your well, you might as well get your water out of a ditch. Thats the dumbest thing I've heard on here since I joined.

landlocked sailor
05-02-2006, 05:28 PM
Gert, I nailed down about a acre (seems like) of cedar shakes on my roof; it makes a beautiful roof but it sure is labor intensive. The most important thing is the sheathing; the shakes must be able to dry. We use 1X4 hemlock in a "skip-sheathing" pattern. This gives a nailer every 8" which is the reveal for 24" shakes. We put a 8" wide strip of 40lb. felt over the tails; a layer of shakes, a layer of felt over the tails, another layer of shakes etc. The felt is then under two layers of shakes. Sort of a belt & suspenders approach. At the peak we put a strip of alluminum coil stock under the peak shakes. The oldest part of the roof is now 16 years old and so far so good.
Regarding fire rating, we had a major house fire in '99. The fire burned quickly through the roof and so had less 'lateral spread'. The wood roof has never been a factor in our fire insurace rating.
Rick

mariner2k
05-02-2006, 08:32 PM
You could cheat and use Ice and water sheild on the entire roof under the shingles. Guaranteed not to leak no matter what the shakes do. But you still need venting on the ridge and under the eaves.

gert
05-03-2006, 09:07 AM
LLSailor:
Thats exactly how I layed them; it is labour intensive but it's pleasent work. Another point, don't drive the nails so hard their heads set into the wood, they should be slightly proud and hot dipped galvanized of course.

The roof that's being replaced I layed 30 years ago and they wern't treated, so thats pretty good service.

Paul Girouard
05-03-2006, 09:39 AM
Gert you layed them right:) Bob S. advice is right on about the zinc.

Lefty "Moss -B-Gone "for your roof , I've heard Tide works as well , Phosfates(sp) in it IIRC do the moss killing .

I'd recomend against shakes for fire reasons , but that really depends on the area you live in , in Ca. IIRC shakes are a no no , wild fires . Here in Pac N West not a issue, fire can't burn all that moss off.;)

The other reason I'd not recomend shakes is the quality of the wood . Your roof will be a proving factor , even with them treated I do not think you'll get more than 15 years of service out of them . Please report back in 15 years to let us know :D

Paul

gert
05-03-2006, 12:13 PM
15 YEARS!

Ya havn't seen the quality of cedar we use for roofs up here. The main house roof is 15 years old treated; looks as good as the day they were layed, colours changed but their butt ends are perfect (thats were they deteriorate from)
The shakes are ALL 100% edgegrain old growth, they are amazing, minimum butt thickness of 1/2", some as much as 3/4". There is also no trees dropping their sh#* on the main house roof; leaves n stuff are the real killers of shake roofs.

Bob Cleek
05-03-2006, 12:48 PM
Odd... I haven't seen a new wood shake roof in CA in a long time. They are illegal here. If you have one, you can keep it, but you can't replace it when it's worn out. They are a huge fire hazard. Nothing like a roof full of dry shakes to take fire when the embers start blowing.

Gonzalo
05-03-2006, 02:30 PM
My next door neighbor is a roofer specializing in cedar shake roofs. He told me he uses a copper strip under the ridge cap to fight the organisms that stain the roof. His roof has been on for nigh onto 20 years, and it looks perfect except for the weathered color.

Bob Smalser
05-04-2006, 12:03 AM
My next door neighbor is a roofer specializing in cedar shake roofs. He told me he uses a copper strip under the ridge cap to fight the organisms that stain the roof. His roof has been on for nigh onto 20 years, and it looks perfect except for the weathered color.


Here you need zinc, because it's more reactive.

Moss is merely a cosmetic problem on composition, metal and tile roofs because its tendrils don't penetrate far enough to do any damage. In fact, climbing on the roof to clean it often does more damage than the moss, and powerwashing composition shingles is popular but usually takes years of life off your roof.

Cedar shingles and shakes here in moss country are a different story....postponing their drying by leaving an inch of moss on them likely shortens their lives, although top-quality WRC heartwood shingles can last 60 years if installed properly, moss or no moss.

But installing them properly doesn't include nailing them to a plywood deck covered with felt. They need air on the undersides, too, and that means solid cedar skip sheathing and no insulation installed between the rafters. But on plywood's the way they are usually installed, and if you do it that way plan on replacement in 15 years.

Also, as most introduced plants flower here long before it's warm enuf for our introduced European Honeybees, our native Mason Bees find great habitat in the gaps between cedar shingles to the benefit of your yard's gardens....especially if you have any fruit trees.

Today's fire retardant polymers added to storebought cedar shingles make them fully acceptable to local building and fire codes here.

Paul Girouard
05-04-2006, 12:18 AM
although top-quality WRC heartwood shingles can last 60 years if installed properly,

Hard to find on this side of the ditch Bob:o

But installing them properly doesn't include nailing them to a plywood deck covered with felt. They need air on the undersides, too, and that means solid cedar skip sheathing and no insulation installed between the rafters. But on plywood's the way they are usually installed, and if you do it that way plan on replacement in 15 years.

I wasn't talking about a inproper install , on 1x4 MTL ,fir not cedar, but skip sheathing.

Also, as most introduced plants flower here long before it's warm enuf for our introduced European Honeybees, our native Mason Bees find great habitat in the gaps between cedar shingles to the benefit of your yard's gardens....especially if you have any fruit trees.

Wonder what the treatment does to the bees?? Can't be good for um :o

Today's fire retardant polymers added to storebought cedar shingles make them fully acceptable to local building and fire codes here.

I don't think they have to be treated in Western Wa. , could be wrong on that we have so many rules who can keep up on all of them. Friggin gestopo / building dept's:rolleyes: They all got there own lil thing to pull out the book and in-turd- pit something new :mad:

Bob Smalser
05-04-2006, 09:58 AM
Hard to find on this side of the ditch Bob


Look for shingle mills. Here's one next door to you.

McLaughlin Bros.
Paul McLaughin
10618 18 th Ave. SW
Seattle, WA 98146
(206) 246-6022

Call these folks in Sumas for more: http://www.cedarbureau.org/


I wasn't talking about a inproper install , on 1x4 MTL ,fir not cedar, but skip sheathing.

DF is fine, providing it's 100% heartwood.


Wonder what the treatment does to the bees?? Can't be good for um


The modern fire retardants are polymers, not poisons. I haven't seen it harm Mason Bees here.

I wouldn't use untreated shingles. That's why I'll buy rather than mill my own when the time comes.

gert
05-04-2006, 12:05 PM
they're treated against fugal growth not fire, rains too much up here to bother with fire treatment.

Bob Smalser
05-04-2006, 01:19 PM
they're treated against fugal growth not fire, rains too much up here to bother with fire treatment.

If you're serious, you'd be well advised to buy shingles treated with fire retardants to a Class A, B or C standard.

From July to October it certainly does not rain much, and my cedar gets so dry it no longer registers on the moisture meter - below 4%.

Tinder dry.

Bob Smalser
05-04-2006, 01:26 PM
Odd... I haven't seen a new wood shake roof in CA in a long time. They are illegal here. If you have one, you can keep it, but you can't replace it when it's worn out. They are a huge fire hazard. Nothing like a roof full of dry shakes to take fire when the embers start blowing.

http://www.cedarbureau.org/faq/product.htm


I heard that wood roofs are banned due to fire risk. Is this true?
I
n general this is not true. Class C fire-retardant treated products are accepted in most areas of California. Due to a lack of product understanding, there does exist a small number of cities/jurisdictions that do not allow wood roofs. However, the CSSB believes that this choice is misguided and has always been a vocal opponent of this type of decision, in the media, legislative, and court systems. Extensive product tests and in-field weathering have proven that Certi-Guard® pressure impregnated fire-retardant treated products do work and do last. Contact the treatment company for more details and technical assistance for your installation and local area.

gert
05-08-2006, 04:04 PM
Done

http://www.imagestation.com/picture/sraid205/pe413cd9a1bfdaad321952f93d309730b/ef1775b6.jpg

Scubastud
05-08-2006, 04:12 PM
only your insurance company knows for sure

Mrleft8
05-08-2006, 09:18 PM
Picnic acid? Dont they make detonators out of that? No.... That's what you get when you eat my mother-in-law's coleslaw..... :D