Hello all.
I have enjoyed reading forums and would like to ask a roofing question.
I am building a garden shed with taper sawn 18″ cedar shakes roof on skip sheathing. My wife objects to tar paper that would be visible if I follow instructions on cedar bureau’s web page for recommended 7.5″ exposure. Would it be ok if I apply shakes in triple ply fashion with 5.5 or 6 ” exposure without the tar paper. I have spent a lot of effort on this shed and would hate to see it wasted by a leaking roof because of a lack of tar paper.
Thanks
Replies
Look again at the Cedar Shake & Shingle Bureau installation guide. The felt covers the top 3rd of each course, so it does not show if installed properly. The felt is mostly for a snow baffle, but it seems you've done everything else properly. Why stop now?
http://www.cedarbureau.org/
Edited 10/1/2002 7:06:29 AM ET by grantlogan
He's talking about it showing from the inside, through the skip sheathing.
I agree with the wife.
What I don't know is the pitch. This is critical to answer the question.
If it is steep enough, you could probably get away with no paper at the 7 inch exposure. Lower pitched roofs need more help.
Another Question that can effect this, are these sawn both sides or true handsplit shakes?.
Excellence is its own reward!
Might it be possible to add a layer of plywood, paneling, or even sheetrock to the inside to hide the tarpaper and give a more finished appearance from the inside? seems like a lot of trouble for a shed, but excellence is it's own reward afterall. I'm thinking thin slices of T-G cedar would look nice!
Dan
Is the sheathing already on? If not, use or T1-11 as suggested and fur on top of it.
Thanks for the suggestion.
Would furring strips need to be applied in vertical and then horizontal direction or would just horizontal suffice. Reason I am asking is that I thought that if only horizontal furring is used it could trap water.
Thanks
I've had good luck just installing them on the horizontal, but I put them down in short (4'-5") sections with a several inch space between them on the butt ends which, in theory, lets the air travel from bottom to top. Piffin's answer is the best solution.
Good Luck
what is so objectionable about felt paper showing from underneath?
Criminy! IT"S A SHED!!!
You gonna spend all your time in it looking up?
I feel better now.
Do whatever you want it's your $$.
T
Do not try this at home!
I am a trained professional!
T,
It ain't the shed he's trying to satisfy, it's the wife.
You know how that goes, don't you?.
Excellence is its own reward!
Hand her a change order for the cost of the assthetic (yes I wanted to spell it that way) Change plus design time and labor and a 50$ administrative fee. Put your money where your mouth is ..... Dear.
T
Do not try this at home!
I am a trained professional!
Using this process, my little cookie cutter owes me about $4.6 million.
Thanks for all the answers.
Piffin is correct, my wife is concerned about tar paper showing from the inside. Roof has two pitches, main part is a 10 in 12 pitched gable roof and then there is an additional about 4 in 12 pitched shed roof on one side of the shed. Shakes are what they call taper sawn, so they look like a shingle, but about twice as thick (5/8 in.) Also my wife prefers skipped sheathing and shingle look, that's how we had it planned, but then she decided that shakes look better and now it turns out that officially shakes need a tar paper. Also I think plywood calls for cedar breather and project is already beyond initial budget.
We are on the island, within last four or five years we have not had any significant snow so I am mostly concerned about rain. Steeper side of the shed faces in direction where most of the wind comes, other side faces forest.
Thanks again,
Reinis
If you go 6" on the 4/12 and 7.5" on the steep side you don't need to worry about leaking. Stagger your side edge laps by 1-1/2" and place the shingles (That's what they are IMO) about 3/16" apart. It'll last a lifetime.
The maun reason for the woven felt is to battle wind driven rain on hand split shakes. The gaps on those can be big enough to fit your thumb up into so it doesn't take much imagination to see rain running uphill in a good wind. The felt extends the headlap for insurance. There are thousands of homes with no felt doing OK. I do recommend it fro shakes and houses but for a shed with shingles there is no reason for it..
Excellence is its own reward!
Thanks for the advice.
Your advice goes along the lines I read in some document on preserving historic shingle roofs. Author of that document said that historically most of wood roofs were known as shingles and word shakes was invented relatively recently and historically even hand split shingles were planed to be pretty smooth. Also it was stated that roof shingles usually were applied in triple ply fashion without any additional felt in-between. Despite that I got concerned when I saw that cedar bureau roof manual does not mention a possibility of omitting the felt and having spent lot of money and effort did not want to see it wasted because of a couple of dollars of felt despite my wife's aesthetic concerns.
Thanks again,
Reinis
I'm sure it will be something to be proud of and not just a 'shed'
Hope you both enjoy it when done.
Excellence is its own reward!
Kand
Not sure "which" island youre on but if the same one I'm on (the long one) then.....I just spoke with someone from The Bureu of Cedar and asked him if I could put cedar roofing directly on plywood. He told me I "could" as long as its on 30# felt. That this area isnt terribly humid or wet. I found it hard to believe that it could be done that way but just passing the info on that was given to me by an expert from the cedar company
Be well
Namaste'
AndyIt's not who's right, it's who's left ~ http://CLIFFORDRENOVATIONS.COM
Just remember that's an expert at the desk with an interest in avoiding liability. Not one in the field.
If this were over living space, I would want that little bit of insurance too, but there would be a finished, insulated space hiding the underside. Like T says, it is only a SHED! dangitall.
Personally, if I were laying every one of them, I would have no trouble with shingles on my house at 12/12 and no paper..
Excellence is its own reward!
Piff
The 322 year old house I bought I'm guessing from the looks of it had its last roof job around a hundred years ago or less, it needs to be redone but isnt in "horrible" shape. And guess what? No one used tar paper.lol
As far as the guy from the cedar B.....I only asked him about going over plywood rather then skip sheathing because I always understood that one would need at least "cedar breather" or something similar. I never knew you could go right over ply w/ tar without venting under the shingles in wet OR dry climates. Reckon I was wrong.
Be well
Namaste'
AndyIt's not who's right, it's who's left ~ http://CLIFFORDRENOVATIONS.COM
Andy,
I think the cedar they used 100 yrs ago is vastly different from what you are able to purchase today, so tar paper was less of a necessity.
As for paper vs not, I can offer anecdotal using true shakes: my house and garage each had shake roofs on skip sheathing, 30 yrs old. The house had tar paper woven in, the garage did not. The garage leaked badly, the house did not. In the attic of the house I never needed a flashlight by day because the gaps in the shakes left plenty of light, we had at least half a dozen birds nests in the attic and uncounted mice - all getting through those gaps, but somehow that roof managed to stay dry.
andy.. the guy from the cedar bureau is full of crap... our area is plenty moist & humid. and some of the shingles will fail within 10 years especially on the lower sloped roofs... they just do not dry between rain storms when they are applied over plywood deck , even with 30 lb. felt...
in coastal NewEngland ( and most other areas , too) wood shingles have to be installed over skip sheathing ofr "cedar breather" not doing so is almost criminal... the high cost of material and labor for red cedar roofs deserves trying to make it into a 30 year roof.. not a 15 year roof..
and most of the red cedar is not old growth like what was installed 50 years ago.. the best stuff out there .. ESPECIALLY what goes to the shingle mills does not have the same tight grain.. nor the same level of decay resistance that the old growth cedar did...
so.. the marginal additional cost of skip sheathing or cedar breather will pay dividends in longer life for the cedar roof...my feeling is the longer life is in the neighborhood of 10 to 15 additional years... so you do the math..
but hey, whadda i no ?Mike Smith Rhode Island : Design / Build / Repair / Restore
ALL
Heres the letter I sent to the Cedar guys that supposidly know best as they manufactor it and sell it......Am I missing something here..........? My question is below the answer below this post
Dear Andy...
With the bowing wind and sometimes snow that you get there at times....
I would just cover all the plywood with 30# felt and put the shingles right over it...
Best...
Martin Obando, Cedar Tech, CSSB.
It's not who's right, it's who's left ~ http://CLIFFORDRENOVATIONS.COM
andy.. the cedar bureau sucks when it comes to plywood and red cedars.. i think they must feel they will exclude too many potential customers if they spec skip sheathing & /or cedar breather.. but i stick by my own observations and research.. cedar shingles on plywood roofs are going to lose half of their life expectancy by not being able to dry out from below..
when you go on a roof that has been rained on for two or three days... the shingles will be soaked all the way thru to the roof deck.. if there is no provision for them to dry out from below, as in an old style board roof with a big empty attic behind it, the shingles will start to rot....
also.. in your case you are thinking about changing the whole dynamics of your existing attic.. going from a skip sheathed roof to a plywood roof.. your old attic may (MAY) have been passing a lot of moisture out of the structure... what is the basement ? field stone ?..with a gravel floor or old beachsand concrete poured right on the dirt.. then that moisture is moving thru the structure.. and thru the floors and ceilings to the attic.... now you plywood the roof.. and put Red Cedar shingles on that WILL allow water thru them right to the felt... nah.. the cedar bureau is out to lunch with their advice about plywood roof decksMike Smith Rhode Island : Design / Build / Repair / Restore
Mike
Sorry bro but I didnt speak to them (The cedar B ) about the house I bought. It was about a house the historic society wanted me to do. A 10x12 shed roof off the main one and thats how THEY wanted it done beyond what I told them. I just wrote to check it out. Probably wont get the job anyway cause I was a bit arrogent with my own beliefs about NOT wanting to do it "their" way. they were trying to save money. A-holes! Anyway...as for MY house....theres no way in hell (dry as it may be there.....lol) that I'd go over plywood. I'm using the old skip sheathing and spending the time it takes to remove every old nail and do it right. End of story! OK? : )
Be well
Namaste'
AndyIt's not who's right, it's who's left ~ http://CLIFFORDRENOVATIONS.COM
ore-ida ...
you had me going there for a while.. think i'll just kick my soapbox back over into the cornerMike Smith Rhode Island : Design / Build / Repair / Restore
Mike
Dont kick it back.....Its Friday night Mikey....just turn it over and set em' up for us....I know you have the lightenin' in yer back barn goin' on brother!
Just me again
yeh yeh,
Andy (to tired to say Namas........It's not who's right, it's who's left ~ http://CLIFFORDRENOVATIONS.COM
Amen. I've replaced 7-8 year old cedar shake roofs installed directly on plywood, and have got some 15+ years old on skip sheathing that are still looking good and will hopefully be good for 10-15 years more.
You were more right than he..
Excellence is its own reward!