What's that above the cinder blocks?

[Aaron Fude]

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.)

Many thanks in advance!

Aaron

[Telstra]

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.

[Lou]

Why not go through the block? Lou

[Aaron Fude]

Actually, what appears to be blue *is* the cinder blocks. My question pertains to the little triangle above.

Go through blocks?! How do you drill through a cinder block?

[gfretwell]

Chip a hole through the core with a mason's hammer or cut it with a side grinder. Then mortar up the hole around the pipe.

[DerbyDad03]

Looks like a brick, maybe a fireplace brick, with a bunch of mortar shoved in around it.

You say you can't reach it by hand so how are you going to get a drill into the area? And if it's mortar, I doubt you are going to want to try and drill a 4" hole in it.

Go through the block.

Determine the location of the vent from either the inside or outside of the wall, depending on which is more critical regarding the placement.

Mark the center of your 4" hole.

Chuck a sharpened length of a wire hanger, long enough to go all the way through the block, into your drill.

Drill all the way through the block (from one side) with the hanger. Start slow and push the drill as straight as possible to avoid bending the hanger.

Now you've a small hole on each side to help you determine the exact location to start chipping away until you have a opening larger enough for the vent.

Insert your pipe and mortar around it to secure it in place.

[Don Young]

I believe it is pieces of concrete blocks and mortar, not a good candidate for getting a 4" hole through without considerable effort and likely surrounding damage to the wall and stucco. If the block cavities are not filled with mortar or concrete, that seems a good alternative.

Don Young

[Ashton Crusher]

easy way is to give it a whack with a hammer and punch a hole thru it. Not in the middle but in the middle of one half.