# How to make cutout in brick wall?



## Raylo (Feb 12, 2006)

I need to make an opening in a brick wall to run PVC vent and intake pipes for HVAC. The opening needs to be about 5"x7" and I'd like to make it fairly rectangular but it doesn't have to be perfect as it will be covered up by a finish vent. Of course it needs to be placed such that several bricks will have to be cut.

As recommended by SABL I got the diamond blade for my 4 1/2" grinder and that should cut fine, but being round I am not sure how to handle the cut in the corners. I suppose instead of trying to cut the opening in place I could cut out whole bricks, cut them down to fit then remortar. But I'd rather avoid those steps if possible.

Anyone have any suggestions as to how best to approach this task, especially cutting the corners?


----------



## SABL (Jul 4, 2008)

The 5" dimension should be equal to 2 full bricks + the mortar joints. The 7" may get a little tricky.....standard brick is 8". How big are the flanges on the vent?? 

How are you locating the vent cut-out?? If you hit a stud or a joist it's back to square one.


----------



## SABL (Jul 4, 2008)

Have a drill with "hammer" feature?? 3/8" x 6" masonry bit will do the job to get the first brick out of the way.....drill a series of holes to remove most of the mortar around the brick and tap it loose. That'll give you a relief area to work from. Or use the grinder and make a series of cuts.....then chip away the brick a little at a time.


----------



## Raylo (Feb 12, 2006)

Vent can only go in this one exact spot due to code requirements (distance to internal and external corners) so no option of going over to whole bricks. This is actually a void space under my steps so no studs or joists... just concrete block behind, I am pretty sure. I'll need to go through that, too. I already did the cut from the inside of the house into the void that included goingthrough the concrete block. That part wasn't so bad.

It needs to go as shown in this picture.


----------



## Raylo (Feb 12, 2006)

Oh, I do have a drill that has a hammer drill function and masonry bits. I am thinking this the way to go by just drilling a bunch of holes around like you said, then using the grinder on the center and a chisel in the corners. That should work. However... since it's suppoed to rain here for most of the next week I probably won't get started for awhile. I don't want to get it open and then have a long rain delay. Fishing the pipes may be an issue. I have a good (I think) way to do it but you never know for sure until you try something.


----------



## SABL (Jul 4, 2008)

That appears to be a softer brick.....make the general outline cut as deep as you can and a few relief cuts in the center. Chip away.......save the brutal work that can chip or knock the bricks loose for after the outline has been saved. Shame you can't get to a mortar joint or two......there has to be a few inches of leeway in the code requirements. Most vents of this type are only a few feet above grade around here.

What.....a little rain?? Looks like a good place to hang a tarp for protection.....just make sure you have a GFCI.....(just kidding....I wouldn't do it in rain, either. BUT, do make sure you have Ground Fault protection even if it is dry outside!!). 

Let us know how it goes......


----------



## Raylo (Feb 12, 2006)

Thanks for the tips.

This place was built before builders started using the high eff furnaces so there is no good place to run such a vent. The code for Cat IV condensing furnace vents is really a PITA. In addition to the corners the pipe has to slope up at least 1/4" per foot. I don't have a basement so the pipe needs to exit the house at joist level and go up from there. I could perhaps go out a little lower starting out under the studwall double header but then I'd have a very low pipe in my util room. Oh, and since the vent pipe passes thru an unconditioned void it must be insulated. I found some 2 1/2" Armaflex that slipped right over the pipe for that.

And the lower level of the house is finished except for the utility room. That and the 25 foot run to the back of the house negate that option since the vent would terminate right below a deck... another code no no. Good thing because I'd have a ton of drywall work to do going that way anyway.

The issue with the coming rain is that I don't want a mess out there for a week if I get held up.

I'll post a pic when I get 'er done.


----------

