It looks suspicously like a slab of Polystyrene to me. Try
poking it with a rod to see if it's soft ? The blue colour
looks like some kind of paint.

"Aaron Fude" wrote in message
...
Hi,

I'm installing an exhaust fan in a thirty year old one storey addition
that's built of cinderblocks with stucco on the ouside. I'm looking
for an alternative to making a vent hole in the roof and I may have
found something.

In the following pictures you are looking at the crawl space under the
roof where the roof meets the old wall of the house. In the very
corner, there is a "wedge" where there are no cinderblocks and I am
wondering what kind of material that is. Is that something that I
could drill through to make a 4" opening? (It's in a place that I
can't reach by hand but would be able to fish the vent through.)

http://freeboundaries.com/stucco.jpg
http://freeboundaries.com/stucco2.jpg

Many thanks in advance!

Aaron