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We adjust overlap as pitch of roof increases. A 3/12 or less gets 19in overlap, up to 4/12 is 9in over, and everything else gets 2in overlap. 15lbs. felt is crap/waste of time- try to use 30lbs. as often as possible. It does give a LITTLE insurance until roofing is complete, and if applied correctly, it may stop a pin hole leak from a `shiner’ or a poss leak neat rake edges via windy rains. Who really knows if the TP will hold water when it cant be seen? Plus DayGlo orange looks cool when chalking on black. Also-Ive read many articals over the years stating shingles will age very quickly and become brittle if applied without TP. The wood wicks the moisture from the asphalt and may cause blistering when they begin to bake under the suns heat. The felt will act as a buffer between the two surfaces. Ever torn of a roof after 25 years? Notice how the TP drifts away like a piece of tissue? Dry as a bone. Then there are the easy tear offs which dont have the TP- usually there are spots of asphalt residue on the decking, and huge cracks on the shingles.
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Andrew, Roofer's Select is great stuff and in my opinion worth the extra money because it goes on dead flat with no wrinkles. HOWEVER...If you leave it exposed to sun and moisture , it will act just about like regular tarpaper and wrinkle all up from the evening dew until it dries out in the sun. It is much stronger than regular paper and holds up much better if you are delayed putting on the shingles.
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.......We switched to 30# felt about 6 years ago, so we could sleep in instead of getting out in the middle of the night to tarp some customers home.
didn't like the way it wrinkles up and stays that way, even to the point of having to slash it and mash it.
Switched to Certainteed's Roofers Select about 2 years ago and now that's all we use....like G.L L says . if it gets soaked over night , it'll lay down tight again as soon as it drys.......
Don't know about the lap, I always overdo it....but I think I like the two inch lap for 6-pitch and steeper and a 6 inch lap down to 4-pitch...........
Hey, killing two birds with one post, there was some discussion about Galvanized roofing nails....we always used Hot Dipped, but now that we do 75% gun nail we use Only Paslode, they seem to have the best coating of the gun nails
and my roofing friends tell me they have fewer jams with Paslode than any other brand....
*Air or gas? Electro or hot-dip?
*We have Paslode and a Makita coil roofing (air) nailers, both are good, the Paslode is better though. Only gripe is a few "double whammys" on occasion and coil jamming due to bent coils. Coils seem to hold together no matter how far you drop them off the roof. Why are some EG roofing nails silver and others have a brass look to them? How far does everyone overlap the ice & water shield? (AKA-mutant duct tape) and how many rows up do you`s go?
*Wow,I knew someone other than me read those irritating wrappers. So Matt what percentage of roofs do you think get done with the felt applied in that matter?joe d
*Tom the Tool Man. How many rows up the roof the ice & watyer shield goes is defined by the codes. the 1996 BOCA code Section 1507.4 requires that ..."{it] shall extend from the eave's edge to a point at least 24 inches inside the exterior wall line of the building."The 1997 Unmifor Builing Code (UBC) Tasble 15-B-1 for severe climates reads the same as the BOCA code.Th e CSBO One And Tow Family Dwelling code, Section 903.3 reads the same as the BOCA and UBC codes. Today's 15 pounbd felt is no longer 15 pounds. In my book, _Complate_Building _Construction, 4th Edition, published by Macmillan, I argue against the use of non-standard felts. Only felts that comply with American Society for Testing and Materials (ASTM)D4869 or D226 must be used. Hope this helps. GeneL.
*Joe D. maybe 10% ? Gene, yes you`ve got to get past the walls/overhang, but would it be practical to go up 3-4 courses on a marginal pitch (3/12) roof for added protection? We usually have Grace brand underlayment, I recall there is a striped line about 2" down we use as our overlap guide. Dont remember what wrapper says.... Is the "new" 15lbs. felt lighter? Globe products is pretty popular up here, but the last time I used their 15 lb it was like newspaper.
*If i remember, most of the bitumen underlayment has gravel on it to make it less slippery for workers; that strip at the top is smooth so it will bond to the overlying strip. I read someone who said he routinely uses bitumen over the entire surface of roofs shallower than 3/12, and the code has something on this that Gene doubtlessly knows off the top of hbis head. Anyway, I plan to use it on a 2/12 shed because I figure it's too shallow to rely on gravity to drain water off the shingles -- a breeze or a clump of leaf litter will be enough to back water underneath them.One downside -- unlike tar paper, there is no way water vapor gets through the bitumen. So venting or air sealing of the roof must be very important. Also, the bitumen is expensive (but so are leaks).
*.....Sorry bout that..we use Paslode NAILS only..our guns are 1 bostich & the new one is Hitachi NV45...the Paslode nails work best in both.
*Gene....went to the lib. and ordered your book, came in two days later from Ashaway...man ,...that thing has been thru a lot of reprints..the one I got was by Audel and seemed a little dated in some sections....anyways , looked like a good source book , nice work !
*Before Gene chimes in, I'll save him the trouble and relate that the publisher wouldn't -let- him revise more than a few sections. Hence the 70's feel to some of it.(He probably wanted too much money.) :)
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Phillip, I started using 30 # felt a few years ago when 15# turned into junk. Even the 30# today seems only as good as Quality 15 used to be. Generaly lap 2 in. and use button nails . Prefer G.P. felt the best. I often thought of skipping the felt, but just goes against my better judgement. Have torn off 25 year old roofs that had none. Just finished up shingling a roof and ran a torpedo heater in the trusses to get the felt to lay flat! Got to love winter!
*Guys,Any opinions on the length of time 30# felt can be left exposed to the weather, and prevent water penetration into the building.I move pretty slow up on the roof, and the quality of my work suffers when the temperature drops, so the felt may have to survive the winter.Craig Turner
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Gentlemen. anyone puirchasing my book should be sure to get the 4th Edition, with my name on the cover. I'm well aware of the book's shortcomings, but as andrew d noted I was not allowed to do a 100% rewrite of the book.
"The director of Technology and Research of the National Roofing Contractors Association (NRCA) claims that the ability of felt to absorb moisture causes it to swell up and wrinkle after the shingles have been applied. It is this swelling up between the shingle nails that gives the roof its wavy appearance. Spokesman for the Asphalt Roofing Manufacturers Association (ARMA) argue that it is the use of non-standard felt that causes the problem. Only felt that complies with ASTM D4869 or D226 should be used. The ARMA representative further added that leaving the felt on the roof exposed to weather and drenching rains for a month or two does not help."
This is a qote from page 338 of my book.
"Commercial roofers have seen the quality of felt decline over the years. The elimination of rags in the manufacture of felt around 1945 reduced the tensile strength of the felt and increased its ability to absorb moisture. Non-standard felt, combined with poor or indifferent installation spells trouble. So does improperly applied ASTM specified felt." (Page 339.) GeneL.
*While we are on the subject, what nailing schedule is used for the felt? I'm betting there is a lot of variance. Yes?Rich Beckman
*Rich,come on man.....A nailing schedule for felt? You are just yanking my chain aren't you?Ok here is my schedule......nail it on fast and flat with as few nails as you need to hold it in place till the shingles are installed.I adhere to this schedule religously on each and every roof I do.AS a bonus tip.....Since my felt is never exposed to rain or dew I don't care how much freaking water it could absorb....It ain't getting wet in the first place.Good Luck all,stephen
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Stephen, As a roofer, you have the luxury of tearing off only what you can put back on in a day! A builder has a much different problem..namely covering the roof sheeting as fast as possible before it gets rained on. After throwing up 30 or 40 trusses and sheeting them, it is pretty hard to paper and shingle the roof in a day!! In fact it may take several days to get to the shingles and this is where it's so important to have a paper that still lays flat and holds down. Premium grade papers like Roofers Select are much better for this type of application as far as I'm concerned.
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G. La Londe,I don't consider it a LUXURY to tear the roof off of someones home ,potentially exposing all their worldly goods to the elements. I consider it a responsibility,a very real resposibility with huge financial implications for me and my customer.THAT'S why I roof whatever We tear off each day,and if a storm arises before we finish shingling for the day we TARP the felt.
Also,I just don't see installing felt flat to be that difficult.I do it alone all the time,and with a helper it's even simpler.I also do a lot of small roofs for a builder who felts the roof before I get there with 15# IKO felt which has to be the cheapest,bubbliest felt imaginable when wet.It also dries out even flatter than when freshly installed,if you let the sun hit it a few minutes.Someone here has already mentioned that the roofers select bubbles up when wet just like regular felt,so what is the benefit to using the roofers select?Just install the cheap stuff flat in the first place.Don't confuse marketting with actuall value.
Good Luck,stephen
*Stephen,Actually, no, I am not yanking your chain. I am slow to respond because I was hoping to get to the library so I could be more specific. But I guess I'm not going to make it.The first roof I did (a rental for a good friend of mine), I researched in the library. I don't recall the book, but the writer was very specific about nails in the felt: something like three rows and every sixteen inches (or more?). Anyway it was a whole sh*tfull of nails. I dutifully followed those instructions, but it didn't make much sense to me and I've used a bit fewer nails each time since.Thanks for the info.Rich Beckman
*Dear Rich,Steve Zerby and I just completed a huge roof renovation project on the south shore of Boston. Due to sequencing problems, vast areas were exposed to direct ocean wind and rain for weeks. We used Roofer's Select, half lapped, with cap nails spaced 18"oc in both directions. This installation proved to be bomb proof and secure under the worst conditions of weather and foot traffic. We could see waves pounding so hard that they splashed over the top of the light house. After a soaking, RS dries out perfectly flat. In fact, it looks so good after drying that we think it shrinks tighter.Underlayment makes the roof, and I won't every use cheap product again. Using this nailing schedule, I'm completely comfortable leaving an occupied house without tarps.Happy '00, Fred
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Your right Roofers Select is exelent much better than shinglemate. We nail it diamond pattern 18" in the middle 12" on laps, sometimes more.plastic cap buttons are the way to go rather than just roof nails. we uselly paper from the top down as we rip,and backflip the laps as we go down that way were not walking on the paper.Here in Massaschusetts papering in a roof is code as well as eaves flashing alias ice&water shield.
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A quick tip Ive learned on applying felt is to nail or staple it in the top corner only (use 5 or so fasteners) then roll it out as far as practical to keep it straight and wrinkle free before finishing it off. I also put the fasteners directly over rafters as I go along in order to use them as a guide where each rafter or truss is located to make faster roof jack/foot hold placement.
*Back to the posted question...2" toplap, 4" sidelap. Page 439 of "Carpentry", 2nd. edition by Koel.Somewhere else in there was the suggestion to keep lenghts under 10ft. to minimize wrinkling. An added note to the felt or no felt talks...states it (underlayment) prevents direct contact between shingles and wood sheathing, which may contain resins that can cause chemical reactions that are damaging to asphalt shingles.Jeff
*I don't think it makes a rats rear how much you overlap the freakin' felt. If the shingles and flashing fail, who cares? Felt is nothing more than a second (a weak second) line of defense. It's only a cheap way to dry in the house before the shingles go on. I never heard of anyone who had a roof leak because the felt was put on "not to code". If you're putting your trust in the felt, then I guess you don't have a lot of faith in your roofer.Code for roofing felt......Good Lord.....what next?My opinion,Ed. Williams
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I dont use felt anymore unless it is code where we are and then we use 1/2 in staples to hold it down.I have torn roofs off that dont have felt on and the roof deck is fine.Have seen where felt paper was used there are water marks and damage to the roof deck as it acts as a vapior barrier.It also makes a better looking roof.
ted
*Felt is code most places now and is required by most manurfacturers because of wind driven rain. during a north east storm rain blows sideways sometimes.It is also required to achive a class A fire rating.And is as I always Thought good common sence.You guys that dont use it are my job security because when it leaks and your no longer around ill tear it off and do it right.RegardsRoofer Jim
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Hi Fred,
Back home to successive nights of fifteen below and frozen traps in the bathroom. Why did I ever leave Cohasset? It was luxury living!
I second Fred's raves about Roofer's Select. I'll never use anything else again. Double lapping the felt (18") and the Hitachi cap nailer and you can be in a bombproof roof in one day easy. God bless the tar-paper shack!
As Fred said, we had huge winds and 60 square of roof. The only time we had any problems was when part of the roof was left completely uncovered by another crew, or when some one stepped in a valley and tore it.
As an added benefit, it's much more secure to walk on. It has some texture and a lot of tear resistance and even at 10/12 pitch you could keep pretty good footing.
Steve
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Jim
Got to tell u i have been doing it in the same area now for over 18 yrs and have no problem at all,I can't remember the last leak I had,the roofs still look good and weather just fine.It works for me and others.
ted
*I could go with Stephen who says that a nailing schedule for felt is ridiculous, and maybe even Ed who says that the amount of overlap is not significant, but no felt?? So I guess all those code officials don't know squat?And, here's the bad news: One of the biggest problems in construction today is that someone finds an easier and/or cheaper way to do something. After a while they start to think that the shortcut is the best way. Then they teach it to some of their helpers... and the cancer spreads. That's why quality and pride in workmanship is becoming an increasingly rare bird. This is Fine Homebuilding - not quick.tract.building.com!
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Amen.
*I definitely have to investigate that Hitachi Button Cap Nailer. It sounds like a very usefull tool to me.I have been thinking about the economics of the felt as Steve and Fred report.I think someone mentioned that it is priced like 30#,which in my area is about twice as much as 15#. Then Half lapping it as Fred reports would about double the material cost again plus the addditional labor.It seems that now we are at a cost(at least in my area) where you could begin at least thinking of icegaurding the whole roof.In my area,on a smallish cape cod style roof the cost would actually be workable.(probably not on the roof Steve and Fred were on though,and I doubt the icegaurd would have sealed down anyhow)Fred and Steve both report the application to be Bomb-proof. But Steve mentions a couple of minor problems due to human error(another crew leaving a section uncovered and someone stepping in a valley and tearing the felt). This gives me reason to pause. If I am involved in a tearoff,one way or another, a couple of times a week X maybe 30-35 weeks a year then I am looking at a lot of opportunities for human error to rear its ugly head and cost me a lot of money during an overnight rain storm(assuming that I left the roof of an occupied house only felted in).Thats why I make every possible effort to completely shingle and flash each days work as standard procedure,and if rain catches me with my pants down in the middle of the day I tarp the felt as a back-up.(luckily,Big Blue and Baby Blue only have to come maybe once a year---if that)I just don't have the guts to leave roofs under felt only ,no matter how good the felt.Gotta think about the icegaurd, though---and definitely look at the hitachi gungood luck all,stephen
*You're not coming to the reunion?!? But you were going to get to be the piñata! (figuratively speaking)Tsk, tsk, being illiberal to liberals ... how conservative ...
*I second Freddy's regional relativism. I've lived in New England, grew up in the arid climate of Los Angeles, etc. Haven't done Texas yet (other than a sweltering visit to coastal Houston), but I know Dallas isn't famed for its Nor'easters! Continually forming and melting ice and snow also make life considerably harder for a roof, not to mention everyone who lives there. Sure is pretty having, though -- we just got 4" today, the first real snowfall in over 2 years. (Of course, in the mid-atlantic/D.C., 4" is enough to close the schools ... ha! I walked for a while this morning with an Alabaman who was just looking in wonder at it all. I warned him not to try to vacuum it up.)
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Its good to hear from another new englander who knows real roofing.
*
Stephen, ABC Supply, over by the Goodyear Air Dock, has a few of those Hitachi's in stock. I'm sure you could test fire theirs before you decide. They look pretty good to me.
John
*Thanks for the tip JRS. In fact I have a credit ap. from there thats been sitting on my desk for a couple of months waiting for me to complete it. This would be a good excuse to hand deliver it.(But then you know I would be taking a little business away from CC Supply and I would HATE to do that since they have ALWAYS been so good to me. Its a little moral dilema)Fred L,There are a lot of roofs here that I could COMPLETELY icegaurd for less than an additional $300.Maybe a lot less if I started buying the stuff in volume.Now that would be a "bomb proof "roof.As you know,if you keep that stuff cool,and install it with enough manpower it goes on very quick,and very easy.It would also make the finished product leakproof under just about any imagineable circumstances.I don't think cost would be a big factor if I actually put this in to effect. Is there a technical reason that would make complete application of this product detrimental to the building?Just wondering outloud?,Stephen
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Steve its a good idea to have credit at several suppliers beacase you can shop price on commodity stuff. We by Roofers Select felt by the pallet as well as Ice&Water and Hitachi gun nails.You can save on the big picture.
Regards
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Sorry for this second post Fred,but I wanted to mention that I think I had your comments in context.I was just thinking outloud trying to apply the info gathered on the job you and Steve described----and to see if it would be usefull or even applicable to my standard situations.
thanks for the help,stephen
*Roofer Jim,that's good advice.My problem is,(and it is not even a problem---it is just a fantastic reality)that my usual supplier has always given me such outstanding help,friendly ,personal service,refered customers to me,and helped me out in so many ways that I would feel guilty spending a nickel anywhere else.I have been looking at the idea of buying Pasload Coil nails by the pallet though.good luck, stephen
*.........Roofers Select (4 sq roll), by the onesy-twosy, is about $17 here...how much per shot for the Hitachi buttons ? and how much for the gun ? apx. would be fine...do they come in coils ? how much & how many to the box?
*
Some of u old timers should dig out some of your old books and look up why felt paper was created in the first place. I looked for answers before I stop useing it,then if u want to call us hackers go for it.
ted
*Hey Winster, We already told Why Felt is a basic nessecity.Maybe you didnt read the prior posts.Bottom line,you probably leaned from a hack and dont know any better.About books as you mentioned I think there are plenty of books out there written by hacks for hacks. My suggested reading for you is to order the NRCA steep slope roofing manual call and order it 1-800-323-9545.
*Jim all i can say is I'm one lucky hacker,also I live in newengland myself.the best to ya, ted
*Well if you work in Mass. thats against state code, not sure about the other new england states. but if you use fiberglass shingles thers no fire rateing also.There is a building inspector on the south shore that is known for making guys rip off the roof if he sees no felt.Mostley on new construction were the poor guys dont get paid shit anyway.Thats probley why they dont take the time to apply the felt.Do you also sidewall with no felt or Tyvek?Sorry about my bad grammerRoofer Jim
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We have got two stodgy-old-set-in-their-ways carpenters on the job site and we have method of work disagreements regularly. The currant one involves felting in a roof. I maintain that the second line is the proper overlap (aprox 9") while Tommy says that the first line (aprox 2") is all that is required. Can we ge a consensus here?
*We overlap at the 9" line and use 30 lb felt instead of 15, which is code here.
*Just throw that stuff out and put the shingles on! If water gets through the shingles, the roof is going to leak.Guaranteed!Blue
*Here in Carolina our CABO building code requires a 2" lap on the horizontal seams and 4" lap on the vertical seams. I like using a 3" and 6" lap respectively and 30# felt as it doesn't blow off so easily. If hand nailing, button cap nails help too.There's a new felt out which is the thickness of 15#, about the cost of 30#, and is supposed not to wrinkle (shrink/expand) like regular felt plus is supposed to be less prone to blowoff. I forget who makes it and have never used it myself. Anyone else used it?
*We adjust overlap as pitch of roof increases. A 3/12 or less gets 19in overlap, up to 4/12 is 9in over, and everything else gets 2in overlap. 15lbs. felt is crap/waste of time- try to use 30lbs. as often as possible. It does give a LITTLE insurance until roofing is complete, and if applied correctly, it may stop a pin hole leak from a `shiner' or a poss leak neat rake edges via windy rains. Who really knows if the TP will hold water when it cant be seen? Plus DayGlo orange looks cool when chalking on black. Also-Ive read many articals over the years stating shingles will age very quickly and become brittle if applied without TP. The wood wicks the moisture from the asphalt and may cause blistering when they begin to bake under the suns heat. The felt will act as a buffer between the two surfaces. Ever torn of a roof after 25 years? Notice how the TP drifts away like a piece of tissue? Dry as a bone. Then there are the easy tear offs which dont have the TP- usually there are spots of asphalt residue on the decking, and huge cracks on the shingles.
*Greater overlap with decreasing pitch makes sense if you picture water backing up -- a greater overlap is needed to maintain the same vertical rise. I think the tar paper makes a difference, at least from what happened here when some put the drip edge over it instead of under.I think the "better" 15# tp mentioned is Certainteed's (?) Roofer's Select ... Freddy raved about it, and I have a roll I'm going to try out .. along with a lot of bituminous membrane for a 2.5/12 roof. I expect that wind will blow water under the shingles at least a couple times a year, and any ice or snow accumulation will make it easy for water to back into them.Pretty stubborn old carpenters to dig in over a few inches of cheap material. Why not just do it your way to make you shut up? :)
*Andrew:Actually, all instructions for drip edge that I have seen specified that it goes under the felt at the eves and *over* the felt on the rakes. Here is a sample of such instructions. I have read the same on the back of shingle bundles.
*Yep -- i omitted that detail -- this was over the felt at the eaves.