HERE YOU GO FOLKS:  Here is an industry insider that disagrees with me.  He is out there, like so many ill informed people, providing a disservice to the community only because of bad methodology!   
You have to scroll down to see the insulation guy chiming in to protect his livelihood.  Go to the next posting of this video below where a spray foam guy says that I am crazy and perpetuating internet myths.  Decide for yourselves. 

IN A NUTSHELL:  IF YOU HAVE AN ASPHALT SHINGLED ROOF YOU SHOULD HAVE IT VENTILATED BENEATH THE ROOF SHEATHING.  THAT IS A SIMPLE TRUTH AND THESE GUYS JUST WANT TO VALIDATE THEIR PRACTICES OF APPLYING INSULATION DIRECTLY TO THE UNDERSIDE OF THE ROOF SHEATHING BECAUSE IT IS AN EASY BUCK FOR THEM.

Robert Wewer1 month ago
 
I just hope that the roof above is not fiberglass reinforced asphalt shingles.  If so, that roof is toast.  These products must be allowed to transfer heat through and into the attic.  That does not make sense either but it is the nature of the beast.  Five years - tops and the roof is toast if it is fiberglass/asphalt.
Reply  ·  1
Hide replies

77Avadon772 weeks ago
 
Total BS! That's a myth and there's absolutely no truth to it. Spray foam does not destroy asphalt shingles. Why would it? Making the attic 65dgs in the summer instead of 140 can only help your shingles. They still have the heat from the radiant sun, but at least they're not getting baked from both sides.
Reply  ·  

Robert Wewer2 weeks ago (edited)
 
+77Avadon77 35 years in the business says you don't know what you are talking about.  Slate, Tile,Metal - OK, but not asphalt roofing shingles!  New Shingles will bake in a short 5-7 yrs.  Either with foam or with fiberglass bats, the heat is reflected back into the shingles and they become trapped between the hot sun and the insulating barrier.  The shingles are getting baked from both sides - you don't get it.  They burn up, plain and simple.  I have photos of many of these problems from the field.  Just take a look at the manufacturer's specs on shingles and see for yourself regarding insulated decks.  Voids roofing warranty for a reason.
Read more
Reply  ·  

77Avadon772 weeks ago
 
No I don't get it, because it's totally untrue. It's a false meme running around on the internet by roofers wanting to scare homeowners into getting new shingles, people have been fiberglassing and foaming the roof deck for decades now without adverse effects. I googled it too, the myth of an insulating roof deck ruining shingles is totally untrue. I know it's untrue because I have a spray foamed roof deck. My shingles are fine, and I live in the high desert, one of the sunniest places on earth with very high temps for half the year.

How would they be getting baked from both sides? LOL!! That doesn't even make any sense!! The insulation stops heat from one side. At best you could make a ridiculous argument for heat on one side, which they would get whether you insulated the underside of the roof deck or not. I'm not taking  your word for it when thousands of experts say your wrong with just a quick search in google as well as my own personal experience with it.
Read more (11 lines)
Reply  ·  

Robert Wewer2 weeks ago (edited)
 
Well watch your roof degrade.  Asphalt shingles and especially fiberglass based shingles which only contain the adherent asphalt, without the base being saturated in the manufacturing process, must have heat pass through them and into the attic.  I am no longer an advocate of asphalt shingles even though I installed them for many years.  I have seen this first hand.  Check with the manufacturers; Check my own website under asphalt shingles:  http://www.fourseasonsroofingandsiding.com/asphaltshingles.htm  .  Before the internet was, I witnessed this firsthand.   Why do you think that ventilation is pushed by the manufacturers?  It is because reflecting the heat back into the shingles will bake them.  Fiberglass shingles will develop striations and then cracks.  They will no longer bridge the thermal movement of the roof deck becoming brittle and cracking along the sheathing joints prematurely.  I have seen this happen with new roofs of only seven years of service. Quite possibly you can incorporate a baffle along with continuous intake and exhaust venting with holes at valleys and skylights, etc.  Become an expert at this and sell value!  Realize the truth instead of becoming entrenched in a wrong method.  That is my advice to you.  I hope you can take a look and see the error of this type of retrofit.   
Read more (14 lines)
Reply  ·  

77Avadon772 weeks ago
 
+Robert Wewer
Keep parroting false information and we'll leave you in the wake of dinosaur builders who did things the old, substandard ways. You're logic doesn't even make sense. If an attic is 140dgs in the summer (very common) shingles would be getting baked from both sides and expedite curling, cracking or striation. Now if we remove the heat from the backside by foaming the underside of the roof deck, the shingles only have to reflect the heat, which is a much easier job then being heated by both sides. Manufacturers are now finally agreeing that foamed decks are meeting and even helpful to their warranties

You're really living in a fantasy land of opinion and conjecture. No scientific facts back up your claims! None!
Read more
Reply  ·  

Robert Wewer2 weeks ago (edited)
 
You are just protecting yourself.  I understand.  You won't look right in front of your eyes at what you are doing.  I feel sorry for you but even more for those whose homes you are destroying.  I am highlighting this discourse so that the public may benefit from your coming forth to expose your bad methodology.   Thank you, at least for that.
Reply  ·  1

Robert Wewer2 weeks ago (edited)
 
I just read your writing on " remove the heat from the backside by foaming the underside of the roof deck."  You are removing the heat from the attic!  The heat cannot move through the shingles!  It is reflected back into the shingles.  The heat stays outside.  That would be a good thing but for the deficits in the roofing that cause this, not in the foam.  The roof is of poor quality.  Don't you get it?  Tile, Slate, Metal - go for it!  Asphalt shingles - advise your client before proceeding or offer a baffle system with intake and exhaust.  Oh and I want to add:  Just forget about New Growth Cedar altogether.
Read more
Reply  ·  1

77Avadon772 weeks ago
 
+Robert Wewer
 The heat doesn't have to move through the shingles. Why would heat have to absorb through the shingles to transfer into an extra hot attic. Asphalt roads have a very cool substrate even when they have a 140dgs surface temp. Yet they don't buckle and rise. The proof is in the pudding, millions of homes have foamed decks and perfectly fine asphalt shingles. I guess they just got lucky according to you.

Again, where is the data and science to prove your argument!?!?!?!
Read more
Reply  ·  

Robert Wewer2 weeks ago (edited)
 
I have published my findings.  If you are waiting on higher thinkers to help you, good luck.  That is just the problem with our industries.  Voices of reason are diminished for the sake of making a buck.  The very "experts" to which you listen will turn on you in a heartbeat to blame the installer when something goes wrong.  This is found in every industry.  Look at my remarks regarding Vinyl Siding.  The VSI threatened a class action suit to silence me.  Look at the "Weather Barrier Statement."   Look at the "Underlayment Craze."  Take a good look at these things and you will find that I am correct.   If you want to get caught in the middle of a storm where you are blamed, go ahead.  I am just trying to help.

Oh and PS:  The roofing shingles will be fine - just for not as long-  I am guessing that the "77" is probably the year you were born....Just about when I got started.   Give a few years and you will benefit from observation.
Read more (10 lines)
Reply  ·  1

77Avadon772 weeks ago
 
Okay just so we're on the same page, you clearly don't have any scientific data to back up any of your claims. That's what I thought before we started this conversation. I trust science, my own eyes, and my own experience over your "findings" any day.
Reply  ·  

Robert Wewer2 weeks ago
 
Ok you trust science and we all came from pond scum and it happened all by itself.  Go on and trust science.  Clearly the roofing industry produces sub-par products that are scientifically made to last for a short time.  Your applications just speed up the process.  It is all about profit and this is put before common sense - just like science.  It is the science of profit and it has been around for millennia.   I am just trying to help you understand the real and tangible elements of the cladding industry.
Read more
Reply  ·  

Robert Wewer2 weeks ago (edited)
 
OK somebody has science on this but I am always skeptical because science always seems to be driven by a cause and this skews results.  Profit is almost always the cause but here is a blurp from ARMA:
Shingle Application Directly Over Insulated Roof Decks

Applying asphalt shingles to insulated roof decks is not recommended unless the following factors are considered:

Directly applying shingles over insulated roof decks is not recommended unless an adequate continuous ventilation space, free of obstructions, is provided between the top of the insulating material and the underside of a nailable deck. Proper ventilation must be provided to dissipate heat and humidity build-up under the rooftop (See ARMA Bulletin 209- RR-86 entitled “Ventilation and Moisture Control for Residential Roofing”). Factors influencing the minimum ventilation requirement include type of construction, roof pitch/run, temperature, humidity, etc. Consult the deck manufacturer, deck system designer, and asphalt shingle manufacturer for specific requirements.
Read more (14 lines)
Reply  ·  

Robert Wewer2 weeks ago (edited)
 
Comparing thin roofing shingles to an asphalt road is not a good analogy.  Neither is comparing a low sloped asphalt built-up roof to a thin asphalt shingle roof.  Asphalt low slopes have been installed over insulation for many years without issue.  Asphalt roofing shingles are the issue.  

I think you have misunderstood my premise.  Insulating the attic at the roof is probably the best thing for most applications.  It is bad for the asphalt roof, which is an inferior product anyway.  You should not see much of this in your climate anyway.  Asphalt shingles should not be installed in aired climates IMO.  Anyway, manufacturers have backed away from stipulations regarding insulated decks (I think because they don't want to affect the bottom line in reduced sales).  They do however stand firm on the ventilation requirement, which blows the the insulated deck out on asphalt shingles.  IKO is one manufacturer that has made investigation into the topic and listed the following:

6. Exclusions 4 & 5 notwithstanding any fiberglass asphalt shingles manufactured to meet ASTM D3462 applied to roof deck assemblies
(slopes > 2:12) where foam insulation is prefabricated into the roof deck system (often called “nailboard insulation”), or where insulation is installed
immediately beneath an acceptable roof deck system, or where radiant barriers are installed, with or without ventilation, directly below the deck, shall
qualify for a reduced limited warranty duration of 10 (ten) years with no Iron Clad Protection coverage, with respect to shingle problems related to
the absence of adequate roof system ventilation (linear pro-ration over 10 (ten) years). The roof design professional is responsible to ensure; 1) the
proper quality and correct application of the insulation and/or radiant barrier, 2) the provision of adequate structural ventilation and/or vapor retarders

Atlas Roofing, a manufacturer has also addressed the issue:  “ Atlas will not be responsible for the performance of its shingles if applied directly to non-vented, insulated decks composed of perlite board, plastic foam, fiberboard, gypsum plank, lightweight concrete, cementitious wood fiber, or similar materials or to any decks with insulation installed directly to the underside of the decking...”

Certainteed is allowing insulated decks with an air space and intake and exhaust.

So I will stand with my original statement that you should be offering a baffle system with intake and exhaust under asphalt shingles.  If the client wants a better roof steer them to metal, tile or slate, according to the sustaining structure.
Read more (36 lines)
Reply  ·  

dekonfrost73 days ago
 
+Robert Wewer robert your wrong and i had to retype this so let it sink in, what cause asphalt shingles to fail is holding heat, thats why a second roof is never a good idea. because both layers hold heat and stay hot longer. the roof must cool quickly and that is accomplished with an insulated deck. also condensation issues are overcome with it. i am a master roofer and i just have to say your wrong about manufacturers installation guidlines gaf,tamco, owing corning,and certainteed all allow this installation with no detriment to the standard prorated warrenties. prove me wrong i know all the reps and have thier cell numbers on my phone right now.so please stop with your nonsense..the heat never has anywhere to build up and shingles never get any hotter than before and cool quicker after sundown but your head around that one an tell me why im wrong 
Read more
Reply  ·  

Robert Wewer2 days ago
 
The manufacturers softened or even omitted the language regarding insulated decks.  The double speak comes in with the retained mandate for ventilation.  How are you going to provide ventilation under the deck when it is insulated tight?
Reply  ·  

dekonfrost72 days ago
 
you only needed the ventilation to disperse the heat and or the exposure to the deck by air that would condense water on the decking due to the difference in wet bulb dry bulb temperature differences
Reply  ·  

dekonfrost72 days ago
 
in fact just now i think i know where the debate was coming from an insulation like fiberglass would cold heat if it wasn't vented with a piece of egg crate spacing. and would have just enough air exchange for moisture to condense.i saw a house like this last year ice water shield 3/12 architectural shingles and it literally condensed so much water it looked like a leak. it was all condensation because water was everywhere evenly dispersed like an aquarium with a humidifier or steam shower...zero ventilation and was super tight. rotted the roof out in 5 years..
Read more
Reply  ·  

Robert Wewer1 day ago
 
Ventilation has nothing to do with the source of moisture.  I have seen the same thing in the summer time above a second floor sauna that was emitting high concentration of moisture.  Looking to ventilation to cure moisture problems is flawed methodology.
Reply  ·  
I just hope that the roof above is not fiberglass reinforced asphalt shingles.  If so, that roof is toast.  These products must be allowed to transfer heat through and into the attic.  That does not make sense either but it is the nature of the beast.  Five years - tops and the roof is toast if it is fiberglass/asphalt.
Shared publicly