Butterfly roof valley installation - InspectionNews

mathew stouffer · #1 (**permalink**) 10-20-2009, 09:43 AM

This looks like a leaker to me, but I was curious if this is a typical valley installation for this type of roof.

brian schmitt · #2 (**permalink**) 10-20-2009, 09:51 AM

the installation screams POS, especially in snow country. would you like a roof design like that for your house. a little over framing with a ridge and a few valleys come to mind

Jerry Peck · #3 (**permalink**) 10-20-2009, 09:52 AM

Quote:

Originally Posted by mathew stouffer

This looks like a leaker to me, ...

They are ... usually anyway.

Quote:

... but I was curious if this is a typical valley installation for this type of roof.

Unfortunately, yes.

That looks like regular 90# granular surfaced roofing, which is not intended to be left exposed to sunlight. Is that fiberglass mat based or modified bitumen instead of felt mat based?

That fish mouth wrinkle is going to allow water to enter.

Those valleys really "should have" a cricket/saddle installed to create a ridge at the center and 4 separate sloped valleys, 2 draining toward each end of that valley.

mathew stouffer · #4 (**permalink**) 10-20-2009, 10:45 AM

Jerry, not sure. Here is the closest pic I have.

Jerry Peck · #5 (**permalink**) 10-20-2009, 10:49 AM

Mat,

The way to check is to try to tear the edge. If it stretches, it's modified, it it tears rather easily and leaves a some fuss along the edge, it's most likely felt mat, if it tears a bit hard and leaves fiber glass fragments sticking out along the edge, it fiber glass mat.

Hopefully, it stretches.

mathew stouffer · #6 (**permalink**) 10-20-2009, 12:58 PM

Fiberglass and felt mat are not rated for that installation?

Jerry Peck · #7 (**permalink**) 10-20-2009, 01:46 PM

Quote:

Originally Posted by mathew stouffer

Fiberglass and felt mat are not rated for that installation?

Some, possibly most, maybe even all, fiber glass mat granular surfaced 90# roll roofing is.

No organic felt mat granular surfaced 90# roll roofing is to my knowledge. The organic felt mat stuff simply deteriorates too quickly in the sunlight and weather.

mathew stouffer · #8 (**permalink**) 10-20-2009, 02:10 PM

Ok, this may be a dumb question, but how can you have a roofing material not rated for exposure to sunlight.

Rick Cantrell · #9 (**permalink**) 10-20-2009, 02:17 PM

"Ok, this may be a dumb question, but how can you have a roofing material not rated for exposure to sunlight."

Good question...LOL

Rick Cantrell · #10 (**permalink**) 10-20-2009, 02:28 PM

Mathew
That is the wrong material (Roll roofing) for use in that locataion (butterfly valley). Also, roll roofing has a much shorter usable life than 3 tab shingles. I would expect it to have serious leaking problems any time from, NOW to 5 years, (most likley NOW).

Brandon Whitmore · #11 (**permalink**) 10-21-2009, 12:30 AM

Nothin like installing the cheapest membrane possible at one of the weakest point of a roof. I'll take it back if it's mod. bit., but I don't think it is.

mathew stouffer · #12 (**permalink**) 10-21-2009, 08:31 AM

Thanks guys. I can't believe no one commented on the angle of the photo

brian schmitt · #13 (**permalink**) 10-21-2009, 09:12 AM

o.k. matthew i'll give it a shot. you are a knuckle dragger! it looks like you would have to have 6' long arms to get that picture?

mathew stouffer · #14 (**permalink**) 10-21-2009, 09:16 AM

Come on Brian, how many knuckle dragger inspectors do you know

I assume you are refering to snow boarding. Anyone can do that, I like a bit of a challenge.