Cinder block wall construction?

[DanielVetpath]

Hi - I purchased an older (about 80 years old) two story building a few months ago. It is rectangular, two story with flat roof and has steel joists. I want to install an exhaust fan in a downstairs shower room and need to run the vent pipe through an exterior wall. I was looking for a spot to take the vent through the closes wall and noticed the joists rest on a couple short rows of bricks on top of cinder blocks. When I looked at the exterior of the wall, it is all cinder block wall (no bricks visible). Can anyone educate me - it appear the exterior walls (at least on the load bearing ends) are two cinder blocks thick. Is this typical cinder block construction? If so, am I going to have trouble making a 6" hole for a vent pipe? Is it ill advised to make a hole on this side of the building? Thanks for any insight, Daniel

 

[sixty4]

Cinder block or cement block? Cinder block I can do with a regular hammer and chiesal Cement block I use a jackhammer drill.

 

[billconner]

A picture of the joist ends/bricks would help but generally, I would hesitate to core through block wall. There may be/probably is some cores with rebar and grout. Would be easier coring to avoid those areas if possible.

 

[Uncle murph]

Hi - I purchased an older (about 80 years old) two story building a few months ago. It is rectangular, two story with flat roof and has steel joists. I want to install an exhaust fan in a downstairs shower room and need to run the vent pipe through an exterior wall. I was looking for a spot to take the vent through the closes wall and noticed the joists rest on a couple short rows of bricks on top of cinder blocks. When I looked at the exterior of the wall, it is all cinder block wall (no bricks visible). Can anyone educate me - it appear the exterior walls (at least on the load bearing ends) are two cinder blocks thick. Is this typical cinder block construction? If so, am I going to have trouble making a 6" hole for a vent pipe? Is it ill advised to make a hole on this side of the building? Thanks for any insight, Daniel

Pick your spot,draw a pattern on the wall and start drilling.Drill with a 1” bit leaving 1” between the holes and slap it with a 12# maul.Should pop right out,mortar around vent once installed.

 

[hefnerconstructionlc]

Use the uncle's method. That is what we do. Pretty easy really.

 

[DanielVetpath]

A picture of the joist ends/bricks would help but generally, I would hesitate to core through block wall. There may be/probably is some cores with rebar and grout. Would be easier coring to avoid those areas if possible.

I will try to take a picture today and post it. Thanks!

 

[DanielVetpath]

Cinder block or cement block? Cinder block I can do with a regular hammer and chiesal Cement block I use a jackhammer drill.

Cinder block, based on external appearance and looking through and existing hole on and end wall. Thanks for the input!

 

[DanielVetpath]

Pick your spot,draw a pattern on the wall and start drilling.Drill with a 1” bit leaving 1” between the holes and slap it with a 12# maul.Should pop right out,mortar around vent once installed.

That is what I was hoping. I just took a look at HD online and was pleased to see 1" bits come in pretty good lengths (18-21"). It looks like I could make it through two blocks from the inside. Thanks for the comment and instruction! Daniel

 

[billconner]

I would think it would still be useful to avoid grouted cores with rebar.

 

[dutchgray]

6" I would do with a diamond core bit, hand held.
Get an SDS drill and punch a 3/8" hole through, that will tell you how thick the wall is.

 

[DanielVetpath]

Here are a couple of pictures from inside and the outside of the same wall. You can see the vertical seam/joint in both pictures which I assume is in the same location (fits without taking exact measurements). Any thoughts about what to expect given these images? I am inclined to try a single small hole per dutchgray's suggestion to see what turns up. Always grateful for the experience and input of others. Thanks, Daniel

 

[Bert_]

That is definitely concrete block...

I'd just start with something small like a 1" bit. Then you can make a neat hole from each side.

 

[DanielVetpath]

That is definitely concrete block...

I'd just start with something small like a 1" bit. Then you can make a neat hole from each side.

Any worries about compromising the integrity of the wall? Thanks for the help - Daniel

 

[NUTTSGT]

I think I would pick a block between those bar joists and not directly under them.

 

[readhead]

The short blocks were to get elevation for the bar joists. There should be a bond beam below the joist bearing.
Drill a couple of holes from the inside and do some exploring before you commit.

 

[DanielVetpath]

Excellent advice - thanks for taking time to comment everyone - Daniel

 

[NUTTSGT]

Excellent advice - thanks for taking time to comment everyone - Daniel

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