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I am working on a ’70’s barn roof that consists of
old diamond shingles over two 1″ layers of styro
insulation over 1×6’s. An ancient layer of cedar
shakes remains on the 1×6’s. I would like to know
if I can feasibly sheath over everything, since a
tearoff would require pulling thousands of 4″
nails and ruin the insulation. Another
complication:4 huge skylights.How can I flash
these without removing to raise to new level? Any
nail guns known to drive
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Hi Scott,
What a waste of money, putting styrofoam insulation over old cedar shingles and then nailing diamond shingles over that with 4" nails.
I must be missing something here.
Regardless, strip it down to the 1x6 clean install a proper system this time. Sheathing over an uneven and unstable combination like you describe would be more money wasted.
Gabe
*Gabe:Thanks for your advice. I agree, whoever roofed this barn must have been rich/crazy. No way the insulation was capable of supporting the shingles. There are areas of bird nests, sags, waviness. I'm sure the roof would look wavy after new sheathing, just wanted to be cost effective and if possible save the insulation, though maybe not worth it. Maybe strip to 1x6 and install new cedar shakes, extra cost offset somewhat by not buying any new she
*Sadly, the effect of the foam was completely negated by the fact that the cedar shingles provided about 6 miles of leakage paths for (I assume) heated air. Look into "nailer board" or if you preferr venting look for "vented nailer board" for application right over the 1x6 strapping.-Rob
*Thanks for the tip, Rob. I hadn't considered the fact that the cedar shakes were venting away all that heated air, good point. Not that you can tell in cold weather anyway since barn is not weathertight and walls are not insulated at this time. Now I'll have to decide if I want to go with T-lock shin
*Yes you do want to go with T-locks! In my opinion anyways.-Rob
*In my opinion,(and that's all it is,an opinion,so it ain't worth much) the T Lock shingle is the UGLIEST possible roof covering imaginable.Pouring a few cans of mobile home roof coating over the existing mess would be a better looking roof.But then, it ain't my barn and I don't have to look at it.Good Luck,(but still cringing at the thought of intentially choosing a T Lock Shingle),Stephen
*Amen Stephen! I give a BIG second to that opinion. Most T-locks are single coverage roofs anyway, and the companies that install them around here charge more for them. John
*Depending on the size of the barn T-lock shingles may be the only viable shingle option. Around here barns roofed with 3-tabs, regardless of color, end up losing several shingles every winter. The locks are the way to go to get the wind load resistance - except for metal.They also seem to last forever; they are definetly thicker than 3-tabs, and after they are installed there are actually a minimum of 3-4 layers of shingle on every square inch of roof. Which may explain why my 40 year old roof didn't leak though it was missing over 30 shingles.Since we have some roofers in this thread - here's a question. The T-lock is an organic shingle, and at over 250# per square is very thick and heavy. What are the primary differences between organic and fiberglass (obviously other then the paper vs. fiberglass substrate)?I think they look great, and I am somewhat of an exterior finish snob!-Rob
*As you may have noticed, I am much more concerned about cost effectiveness and longevity of this roof than how it looks. I think anything other than diamond shingles will be an improvement here, and I don't mind T-Locks for appearance. Last November a big wind blew off a couple squares of the diamonds/insulation combo. It's tarped and is now zoned as multi-family low income bird h
*Rob,I can give you a couple of important differences between the Organic and the fiberglass shingles1)Demand. There is little or no demand for organic shingles by customers in my area.As a result the SUPPLY of shingles marketed as organic just about keeps pace with the demand.Think of organic shingles as the Bias Ply tire being replaced by Radial tires.When is the last time you bought a tire and even thought to check if it was Radial or Bias Ply?2) Fire rating. Your insurance company and your local building department might have some things to say about using organic shingles since the fiberglass have a better fire resistance rating.(This is a bit of a bogus issue in my book since both shingles are composed primarily of asphalt. comparing the diferrence in flamability between these 2 shingles would seem to be like comparing the difference in flamability of kerosene and gasoline)Regaurding the T lock shingles. I will stand by my statement that I think them to be the ugliest possible roofing choice.There are other reasons for their vile reputation.....In my market I have aprox. 130 roofing contractors advertizing along with me in the yellow pages.There are ,in addition,at least that many fly by nights,employees working side jobs,un-qualified handy men,and a few qualified contractors who don't advertise to add to the mix. Conservatively,I estimate at least 260 possible choices of professionals and other life forms to install roofing available to the homeowner in my area.To my knowledge only 2 actively market the Tlock or a similar product.The other 258 despise the product.Why?The Tlock is sold in my area as a re-roofing shingle. The marketing method used is "save the cost of a tear-off by using our shingle"It is used primarily as a 3rd layer roof,ignoring building codes which generally will allow only 2 layers of shingles.The cost of the Tlock roof ends up being as much as or even higher than the price that resonsible contractors charge to tear-off and re-roof a house properly.No new chimney flashing installed,no new step flashing,no new soil stack flashing.Valley flashing is exposed 90# mineral surface roll roofing which in that application will have generally a MAXIMUM life span of 8-12 years. In my opinion(and again it is just an opinion)the purveyors of this slop prey on the ignorant,the uninformed,and the gullible.I am sure the other 258 "contractors' would agree with me on that score.Now Rob,you say that Tlocks are the way to go to get wind resistance and yet your roof is missing 30 of these shingles? Hardly a reccomendation I would care to accept!I could be wrong here but I suspect that your roof IS leaking and you are not aware of it. If it is Not leaking I would suspect you have several layers of shingles under the tlock layer helping you out.If wind resistance is what you are after.....I am interested in some ads I see in Roofing Contractor magazine for Certainteed Hatteras shingles with a 10 yr. warranty against winds up to 110 mph. (40 yr. shingle) sounds like a good product.Agreeing to disagree on this issue,Stephen
*"Now Rob,you say that Tlocks are the way to go to get wind resistance and yet your roof is missing 30 of these shingles? Hardly a reccomendation I would care to accept!I could be wrong here but I suspect that your roof IS leaking and you are not aware of it. If it is Not leaking I would suspect you have several layers of shingles under the tlock layer helping you out."Steve - OK, I guess I hit a nerve with you - sorry.Anyways, the roof I was referring to was one layer over reclaimed lumber with no tar paper. The reason the roof was missing over thirty shingles is because it was almost 50 years old! Unless they re-roofed with the exact brand, color, and stamped pattern as the cardboard boxes for the original shingles indicate. The original boxes were nailed over the hips on the gambrel. I now know that the roof wasn'y leaking because I re-roofed it last fall and replaced not one piece of wood. Since it is completely open underneath I think leaks would have been obvious.I also wasn't a large proponent of roofing houses (though mine had two layers of T-locks over 2 layers of 3-tabs). I believe I specifically mentioned barns. Around here 90 percent of barns do not have valleys, vent stacks, or chimneys. Though I think it's odd that you condemned the whole system over the way installers treat it. Around here T-locks are installed on new construction and tear-offs as well.-Rob
*Stephen, Does your argument assume that anyone dumb enough to use T-Locks is so dumb that they would not install new flashing around chimneys, soil stacks, etc. and why would they (or anyone else) necessarily use 90lb. roll roofing for valley flashing? I don't understand...Still looking at it,Sc
*Scott,I guess my long winded argument can be distilled down to the 2 following points.1)Out of approx.260 roofing "contractors"in my area only 2 to my knowledge(and it is admidtedly imperfect knowledge)will use tlocks or a variationof tlocks.The other 258 contractors,as far as I can tell despise the tlocks.2)The 2 contractors IN MY AREA who use tlocks ,DO NOT for the most part install new flashing.Perhaps the tlock contractors in your area are smarter than these 2 outfits.(I can think of about 258 contractors in my area who are smarter than these 2)The 90# is used as valley flashing(exposed)because they can match the shingle color with it.The tlocks are too small to form a closed cut valley so any flashing material in the valley will be exposed.It is also about 1/3 the cost of metal flashing.If the life span of your valley is only 8-12 years that is the life span of your roof.I won't dispute anyone who reports having a tlock roof lasting 40+years.I don't find that statistic to be remarkable because I have found quite a few 3-tab roofs lasting that long as well.The problem is that this isn't the late '50's ,it is the late '90's.We have to work with the materials available TODAY.I think there are several materials out there TODAY that are better than the tlock.(and,again,in my lame opinion anything would be better looking)Good luck,Stephen
*Stephen:Thanks for the valued experienced advice. I have done a number of roofs but never a T-Lock.Around here (Wisconsin) there are roofers who insist on using it for barns. That's why I asked. The barn has no valleys but does have a cupola, fireplace and four large skylights, which are going to be my biggest problem/challenge. I am concerned about snow piling above them, and flashing around them since it would be a huge hassle to remove them though some locals have advised me to do that too. Anyway, I appreciate everyone's help he
*Stephen,I'm surprised that you have found only two contractors in your area that don't re-flash when they re-roof. I should move to your area, because I find too many people who don't do it..........but then again, these are the people that keep me in business. Too bad it's at the expense of the homeowner.Scott, As for removing the skylights - I don't know what kind of usage you get out of it, or if it's well lit (most barns in my area don't have a lot of light fixtures), but if you feel comfortable with your flashing skills I would keep them in. If it was my barn, I would bring them up to the new level so I knew for sure that they are flashed correctly, and watertight. You have to decide whether you really need them for lighting.Good luck,Greg
*Greg,let me clarify.There are only 2 companies who use the tlocksin my area AND these 2 companies generally do not as a rule install new flashing.There are quite a few other companies in my area that will avoid flashing if at all possible ,but the majority will re-flash.Keep in mind that there is some difference in going with existing flashing in a 1 layer layover(say over a 20-25 yr old roof)and not re-flashing on a 3rd layer installation when the existing flashing has got to be 60-70 years old. That old galvanized stuff is rusted out BEFORE the 3rd layer is installed.The tlocks are generally 3rd layer installations around here.Scott,did I miss something?With the insulation and the skylights has this barn been converted to living space?
*Hey guys,I think this barn was intended to be living space about 20-25 years and 2-3 owners ago. They did install the skylights, insulation and diamond shings, and insulated some of the walls. They must have paid a fortune for the 32 foot stone fireplace. At this time, it is not lived in, but is my workshop, and I would like to have some heat retention for colder weather projects. The insulation has been badly chewed by birds and mice. The roof has two leaks around skylights. The skylights are 8'x10' and 5'x7' (guessing) bubble type plexi with aluminum frames. They stick up about a foot from roof level. Hope your tools are dry,
*A 32 foot stone fireplace?!?! This barn sounds like it would be a fun project in itself. I'm picturing a large screen TV, satellite hookups, a large (well stocked) bar, Sunday football, etc, etc. Of course with your own stuff it comes down to the old "time/money" thing....In my house that means the wife wants me to spend both of my time and money on the things she wants!If it was converted, I'm guessing it's well lit. Dump the skylights if you don't need them. Those one layer plastic ones leak heat like a sieve. You will also have the peace of mind that your tools will be dry.Good luck,Greg
*Stephen,I understood your post the first time, I was just poking a little fun at those who don't re-flash. I'm sure there are many perfectionists on this board, and my wife would love to go into great detail on my own idiosyncracies, but I leave nothing to chance (or past contractors) when it comes to my jobs. I re-flash no matter how old the other flashing is. Occasionally, I will re-use the old counter flashing if it is set in the mortar. I have never had to use my contractors insurance, and I cringe at the thought of how much higher my premiums would be if I did!Greg
*Hi Greg,I'm a ways off from the big screen here. First, a new roof. Then, plug up gaps in siding, fix all windows and doors in lower level, get a heat source and try to keep some of the heat in. True, the skylights let heat escape, but they let in a lot of light, and barn is not well lit otherwise. On sunny days in cold weather, the skylights do warm up the space, not a bad trade for electric bills. The fireplace is beautiful, wish they had put it in the house! No good for heat in the barn, tried it last winter and had to wear gloves to sit in front of it.Just so you guys don't think I'm a complete fool, most of my tools are in a room sectioned off from the main part of the barn-all insulated, drywalled and weathertight! It's just not large enough for all the bigger woodworking stuff.I'll let you know when it's safe to come watch the packers on the big screen and put back
*Go Pack Go!Rich Beckman