moisture from missing singles at roof peak?

Discussion in 'Roofing and Siding' started by rogbngp, Jun 16, 2013.

  1. Jun 16, 2013 #1

    rogbngp

    rogbngp

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    Last Fall I found some roof shingles in my yard and driveway following a hurricane. I inspected my roof and didn't see any missing. But somehow I overlooked that these tiles are missing from the roof peak.

    I can nail them back in, of course. But how worried should I be about any moisture that might have gotten in under the shingles?

    [​IMG]

    [​IMG]
     
  2. Jun 17, 2013 #2

    nealtw

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    I would check the attic for wet insulation.
     
  3. Jun 17, 2013 #3

    WindowsonWashington

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    Check the attic as neal said and while you are up there, get rid of that ridge vent.

    It is the worst stuff on the market and does not work even remotely close to as advertised.

    A wise, old, and crotchety man that I know once said that cobra vent (what you have) looks like a snake eating a rat.

    Put some Shingle Vent II up there when you do the new shingle caps.
     
  4. Jun 17, 2013 #4

    rogbngp

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    Thanks. I don't see any water damage on the attic roof peak where only three shingles had blown away, i.e., in the first of the two pictures above. There is an open slit of roughly about 3/8" between the plywood sheets that adjoin at the peak. But the plywood looks undamaged. The attic roof is not insulated. It's bare plywood.

    As to the second of the two pictures that has about 8 shingles missing, that belongs to an also uninsulated carport roof extension to which I now have no easy access to look inside. So as it stands there's really not much I can do to check. (I guess I would have to cut out part of the adjoining plywood wall in the attic. I could do that, and when I'm finished screw back in the piece I cut out with some cross braces.)

    I'm not really familiar with roof construction. But isn't there typically some sort of moisture barrier under the shingles? Assuming that there is a barrier of some sort (?), I guess my concerns are 1) whether that moisture barrier worked (one area is okay; for the other I would have to check the inside of the carport roof), and 2) whether moisture from rain made its way between the shingles and that barrier over the roof's plywood.

    The roof has a south-facing front, and both affected areas are unshaded. Because of the black shingles the roof gets warm even during the winter--and in the summer the shingles are downright hot. I would imagine that any moisture that might have made its way between shingles and barrier would quickly evaporate... Under that scenario that is my hope, anyway...
     
  5. Jun 17, 2013 #5

    oldognewtrick

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    As W-O-W said, remove the existing roll ridge vent, then you can check the decking edge for possible water issues. Pick up some 4' sections of shingle over ridge vent and a couple bundles of matching shingles. Cut the shingles into 3 separate tabs, angle cut the top edge, install the vent and capping with 3" roofing nails. Problem solved. Shouldn't blow off with the next storm and the roof will exhaust better, provided you have adequate intake ventilation.
     
  6. Jun 17, 2013 #6

    nealtw

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    Oldog: how big should the gap in the plywood be?

    rogbngp : Welcome to the site. You may have a tarpaper type product under the shingles but it won't be under this area at the peak. The exposed matting under the shingle is supposed to vent air out of the attic. So you would think that if air can move thru it water may also move thru it.. The attic should be checked, you don't want mold growing there, if you do have to cut thru the wall do not cut the frame work for that wall, if you have trusses, cutting any part will weaken them.
    Oldog and W O W are suggesting that the mat at the peak is not the best product and should be replaced with better one.
     
  7. Jun 17, 2013 #7

    oldognewtrick

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    On houses with a ridge beam cut 1-3/4" on each side of the peak. On houses without out a ridge beam 1" on either side, stopping at least 6" from the rake edge.
     
  8. Jun 17, 2013 #8

    nealtw

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    Most houses with trusses have solid blocking between trusses at the peak to support the plywood edge, should that be moved down each side to allow for the slot and still support the plywood. I've never had to prep a roof for a ridge vent.
     
  9. Jun 17, 2013 #9

    oldognewtrick

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    My recommendation would be to allow for an air slot at the peak to provide for attic exhaust. Solid blocking will restrict air flow up the rafter bay.
     
  10. Jun 17, 2013 #10

    nealtw

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    We wouldn't get it past the engineer that inspects the framing, maybe that's why we don't see much of it.
     
  11. Jun 17, 2013 #11

    WindowsonWashington

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    They don't require the solid blockers here but that does make sense.

    Interesting to see the variance in the codes.
     
  12. Jun 17, 2013 #12

    nealtw

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    I think if it was left to me I would have blocking evan on flat, and it would give a something solid to nail to when applying shingles. Perhaps a row of 1" holes would work too.
     
  13. Jun 19, 2013 #13

    rogbngp

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    Thanks all! I may post again about this but I think I've got it. Appreciate your time and wisdom.
     
  14. Jun 19, 2013 #14

    oldognewtrick

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    Give us a follow up when you're done to let us know how it turned out.
     

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