Replies

1. 
   Piffin | Jul 16, 2002 07:17am | #1

   I need to learn a little context here.

   What is the pitch?

   What is Eagle Shield?

   How the dickens is this thing framed????

   Is the T&G ceiling 2" thick or wide? if thick is it laid over beam/joists?

   Excellence is its own reward!
1. 
   gibsonc21 | Jul 18, 2002 04:50am | #6

   The pitch 3/12.  The T&G is 2" thick (of course, that means about 1-5/8' or so) and are placed over 8" poplar beams 6' on center.  Eagle Shield is a heat reflector material that looks similar to aluminum foil supposedly dual purpose in that it reflects heat in both directions.  

   As best I recall, there is the T&G, 1" insulation board, Eagle Shield, and then the 25 year Woodline shingles.

   Thanks for your thoughts on this!

   Omar

1. 
   Piffin | Jul 19, 2002 02:33am | #8

   OK, I've almost got it now. One thing still puzzles me. You haven't mentioned any roof sheathing. We've got the T&G ceiling over beams. That's common enough. Then the 1" foam board with foil over it. Then the shingles. I would expect them to be applied to a plywood sheathing or OSB deck.

   It's been awhile but I remember reading some industry studies a few years back that determined that using SIPs and/or rdiant barrieres immediately behind the sheathing could cook the asphalt out of the shingles by keeping the heat higher than 'normal'. (Having worked on roofs which were so hot that the shingles had all the consistency of wet toilet paper blistering my calloused fingertips, I don't know exactly what the industry standard for 'normal' is) Anyway they reported a shortened life span averaging something like 7% less. Maybe having the foil directly in contact with the shingles is helping them cook faster and really boiling the goodness out of it.

   If that's right, let's suppose that your radiant barrier combined with the foam produced something on the high side of that average and assume 20%. That means that we might expect it to have lasted twenty years instead of 25.

   Something else is at work here, it seems to me. Now if the shingles are indeed nailed directly over the foil and foam without sheathing to provide a solid support surface, every bit of walking or live loads such as snow and wind would've worked on the spots where the long nails run through the foam into the 2x6 and worsened things considerably.

   What are the signs/symptoms of your apparent shingle 'failure'

   I'm trying to confirm in my mind whether this is a shingle failure or a roof failure.

   It appears at this point that ventilation is only a minor part of this picture. I have a recommendation in mind for you but i want to get my baseline facts straight first. Look forward to hearing from you.

   A picture would be nice! (of the roof, not of you - LOL)

   Excellence is its own reward!

   Edited 7/18/2002 7:35:45 PM ET by piffin

1. 
   gibsonc21 | Jul 22, 2002 06:13am | #9

   Thanks for your response.  We'll be taking all this off in the next few days so I can let you know exactly the sequence of the various materials. Perhaps this will help others know what not to do in the future!  I strongly feel the Eagle Shield is the culprit.

   Your thoughts and consideration of this problem are appreciated.

2. 
   friendlyguy | Jul 16, 2002 09:59pm | #2

   go with a continuous ridge vent

1. 
   JDRHI | Jul 17, 2002 12:44am | #4

   I missed where he said a ridge even existed.J. D. Reynolds

   Home Improvements

   "DO IT RIGHT, DO IT ONCE"

1. 
   friendlyguy | Jul 17, 2002 03:59pm | #5

   point taken, jaybird; I guess i should have qualified my input by saying "if a ridge exists.... etc. "

3. 
   JDRHI | Jul 17, 2002 12:42am | #3

   Need a bit more info...

   What type of roof? (Gable, Hip, Shed?)

   What is below roof? (Porch, Living space, Bathroom?)

   What is Eagle Sheild? (Sounds like a brand name rather than a product)

   What is the roof framed with?( 3" doesnt sound possible)

   Where is this project?(Climate variences play a major role)

   J. D. Reynolds

   Home Improvements

   "DO IT RIGHT, DO IT ONCE"

1. 
   gibsonc21 | Jul 18, 2002 05:25am | #7

   The roof is a shed type.

   Living space, porch and bathroom are below the roof.

   The approx. 3" space is comprised is the T&G, 1' insulation board and the Eagle Shield which is foil thin.

   The home is in Western Kentucky.

   Thanks for your response.