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I am looking for advice on the proper installation of Cedar shingles and/or shakes. It has always been my understanding that cedar roofing should be installed either a) over skip lathing or b) over one of the new ventilation fabrics such as “cedar breather” over solid sheathing in order that moisture becoming trapped under the roofing can escape. I am seeing lots of new Cedar roof installations here in Salt Lake City being nailed directly over solid sheathing and building paper without any means of ventilation being provided for. Has the convention changed allowing this type of installation or is this “cutting corners”.
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IMHO: This is cutting corners and cutting the life out of the roof. For a while in the 80's , the shingle mfr's were saying it was OK to install direct over plywood roof sheathing, and in the go-go 80's a lot of upscale houses got built with people working with materials they had no personal experience with (red cedar shingles on roofs).
Now enough time has passed that concientous mechanics can see for themselves that the roofs start to show premature signs of failure, mostly because the shingles stay wet for longer periods of time, since they can't dry out on the back. Given the cost of the materials, say $200 / sq.
and the high cost of labor ( career employees with Workmen's Compensation Insurance ) , it seems a little penny -wise to eliminate the extra step and expense of Cedar Breather.
That said, it still happens all the time, usually with a quote from the roofer, "been doing it like this for twenty years and you don't need that stuff" Well, get up on the roof of one of those twenty year old roofs, but step easy because there ain't much to walk on.
Perhaps someone else has a different viewpoint.
*I've never seen this "cedar breather" you guys are talkin' about, but I agree wholeheartedly with what Mike says about cedar roofs lasting a lot longer when they are installed on skip sheathing, thereby breathing. That's the only way I'd do it on my Mother's house.
*I'd like to comment based on some experiance I had in the past. I grew up in the Portland,Ore. area. Most high quality roofs were shakes over lathe. Some roofs I knew lasted 20 years and more. I moved to Houston, Tx. in '81 and at that time cedar shingles and some shakes were being used. I lived there 14 years and saw many roofs curl up and deteriorate due to the extreme heat. Now in the Houston area cedar is no longer allowed being it's a fire hazard. My concern is why would you use cedar for a roof in an area noted for its extreme heat?
*The breather is fabric that comes in rolls, and looks alot like the mesh material found in some ridge vents.
*I think we are all in agreement that a wood roof needs some type of ventilation underneath. I have no experience with the cedar breather, but would love to try it. The big difference between shingles and shakes is that shingles are the protection and shakes rely on the underlayment to keep the rain out. With shakes you will need to install the 30# felt(I'd recommend using Roofers Select from Certainteed) as you install up the slope. There are several books available (Taunton, Craftsman) that show how to do it. Dave
*Creature - "Look, Reach, Pull, Check" what's that mean? (I got a feelin' this is gonna be pretty good!)
*Hope to not disappoint you...those are the four steps to deploy your chute in skydiving..Look for the ripcord...Reach for it...Pull it( a very important step!) and then check to see that your chute is properly deployed, which is always a plus. Nothing like a good jump or two from 10,000 feet to unwind. Dave
*My roofing book is hiding right now, so I don't have a direct source, but, FWIW:I've seen 3 shake roofs in NW Ohio, one 20 years old, one 15, one about 25, all installed on plywood, and all in pretty bad shape. The butts were very mushy, the surfaces in many areas pretty soft (screw driver would poke in about 1/8" with little effort) and, on 2 of them, alot of cupping and curling (the third was in a wooded area, and it had a _lot_ of moss.)I find myself wondering about the cedar breather stuff. The picturs I've seen make it look like maybe an inch thick. How much air is going to circulating near the ridge of any decent size roof?I also wonder what the code inspectors would say about skip sheathing? When I was contracting, I found them a bit, ah, sensitive to anything they weren't familiar with, and I suspect they haven't spent time in any of the thousands of (older) attics with skip sheathing in my neck of the woods (NW Ohio.)Bob
*Bob: I guess the jury is still out on Cedar Breather, but we use it because we usually dont have the choice of doing skip sheathing, what with existing conditions, etc.The Cedar Breather creates a 3/8" air space directly behind the shingles, and apparently that's enough to let the shingles dry out between rain storms. In theory, it should work BETTER than skip sheathing because there is less wood to wood contact, so more drying surface.I try to talk my customers out of wood roofs, I think they get better value for their money with some of the premium asphalt shingles on the market, but there are some jobs where ther is just no substitute for the real thing.I wouldn't hesitate to recommend the CB, and wouldn't do a wood roof without it.
*I always thought that would be fun, but never got around to tryin' it. Now I want an ultralight. When I was 30 I wanted a portable sawmill. When I was 20 I wanted to get...never mind.
*Mike,Thanks for the info. <> But, of course, less air to absorb the moisture. So, who knows?I think you're absolutely right though, wood shingles without air circulation below is asking for trouble.As a home inspector, how will I be able to spot use of cedar breather? Will it be obvious when I lift the drip edge?Bob WalkerNW Ohio
*Bob: if they use dripedge, yup.Somehow, they have to develop a detail that lets air into ALL the edges, EAVES and RAKES and then lets it out at the peak.They have a website:http://www.cedarbreather.com/but the graphics are lousy, they have a nice slick brochure, too, but the graphics arn't much better there , either.I guess it's almost as generic as felt paper, so you can improve on the uses.
*"Look, Reach, Pull, Check"With this cold weather, I thought that might refer to the steps necessary to take a leak while wearing insulated Carhartt bib overalls, over jeans, over long-johns, over underwear. Sometimes I get exhausted with this ritual. Oh well, gotta love winter work!John
*They say it's not the fall that'll kill ya but that sudden stop at the end.Gaby(fellow extreme sports enthusiast)
*There's the old joke about the guy that falls off the top of the Empire State Building. People on each floor heard him saying as he fell past their window "so far, so good!"Rich Beckman
*Look at the underside of the roof,from the attic,around a vent or some other hole, you should be able to see it. Don't expect to see it though,most people don't use it.
*Here's some RC from before we started using CedarBreather
*That is one fine lookin' shack. Did you leave the cedar raw, or put something on it?
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I am looking for advice on the proper installation of Cedar shingles and/or shakes. It has always been my understanding that cedar roofing should be installed either a) over skip lathing or b) over one of the new ventilation fabrics such as "cedar breather" over solid sheathing in order that moisture becoming trapped under the roofing can escape. I am seeing lots of new Cedar roof installations here in Salt Lake City being nailed directly over solid sheathing and building paper without any means of ventilation being provided for. Has the convention changed allowing this type of installation or is this "cutting corners".