- Joe -
But getting back to the IKO answer above - it doesn't explain what
these strips are covering up.

Their logic is that the tape is there to keep the shingles from
sticking to each other. Which means that what-ever is UNDER the tape
is sticky and shouldn't come into contact with other shingles while
bundled. So why put this stuff on the shingles in the first place?

- Nehmo -
Picture the shingle correctly oriented with the granular surface up.
What's UNDER the tape on the bottom of the shingle is the next shingle.
While in a package, the tape is above the adhesive spots of the next
shingle. While installed on the roof, the tape is above a part of the
next shingle where there is no adhesive because each shingle is offset
from the next shingle. Thus, the tape serves a function while the
shingle is in a package, but serves no function after the shingle is
installed.

The *other* adhesive on the bottom of a shingle that holds the tape on
only does that.

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* Nehmo Sergheyev *
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