[John_W]

I need to add a dryer vent pipe in my crawl space and route it to an outside wall.

Currently there is no connection under the floor - just a hole (see picture).

There is a narrow gap (about 1.5 inches) between the floor joist (right side of picture) and the termite shield.

Someone suggested adding a sister to that joist and then cutting a notch in it to allow vent pipe access.

Alternatively, I wonder if it makes any sense to notch the cinder block below the termite shield, patch the shield, and not have to notch the joist.

It seems like less work than putting in a sister. Would that violate code or be wrong in some other way?

 

[Ron6519]

You should not notch the joist. If you put a hole in the cinderblock, will it be above ground outside?
If it will, open the block.

 

[bob22]

Can you go out the side wall of the laundry area without doing this crawl space thing? Looks like a bit of work and tight space to do it in, not to mention potential issues raised by Ron.

 

[John_W]

You should not notch the joist. If you put a hole in the cinderblock, will it be above ground outside?
If it will, open the block.

The top of the cinder block wall is at least 3 feet above ground.

I could also put the dryer on a hollow stand and put a new hole through the floor, under the stand, on the other side of that joist. Coming out of the dryer with a tight 180 degree bend, then a 90 degree bend down through the new hole. It sounds odd, but isn't any more turns than I currently have - it would just go through the floor in an unusual place.

 

[John_W]

Can you go out the side wall of the laundry area without doing this crawl space thing? Looks like a bit of work and tight space to do it in, not to mention potential issues raised by Ron.

That was my original idea. It's the best way in many respects. Any other way will be a pain.

The front porch is on the other side of the wall behind the dryer. (We wouldn't mind that.) The problem is that there is a window above the dryer. Going straight through that wall would put the new vent 3 feet from the window, vertically, but horizontally, it would be at the edge of the window.

It seems that code requires 3 feet in both directions.

 

[joeyr]

Chipping concrete is NEVER fun :thumbdown:

Here is what I would do. The joist you wanted to notch, don't do it. Sister up the joist on the right. (2nd joist in from the concrete) Now shore up the joist you wanted to notch about 2 feet back on both ends of the hole you have drilled.

Cut the joist out 6 inches either side of that hole. (don't worry about the floor falling in, the posts you put under the joist will hold the load once you cut.) Now you are going to make a little beam that sits on the concrete wall and butts into that new sistered joist. Do one beam on both sides of your cut joist and hanger the double beam to the sistered joist with a double hanger and single hanger the cut joist to the new double beam and ta-daaaa, You have a nice STRONG cavity to run your duct down and where ever.. (btw, now remove the shoring posts and ta-daaaa you are done)

Best of luck, Joey

 

[John_W]

Chipping concrete is NEVER fun :thumbdown:

Here is what I would do. The joist you wanted to notch, don't do it. Sister up the joist on the right. (2nd joist in from the concrete) Now shore up the joist you wanted to notch about 2 feet back on both ends of the hole you have drilled.

Cut the joist out 6 inches either side of that hole. (don't worry about the floor falling in, the posts you put under the joist will hold the load once you cut.) Now you are going to make a little beam that sits on the concrete wall and butts into that new sistered joist. Do one beam on both sides of your cut joist and hanger the double beam to the sistered joist with a double hanger and single hanger the cut joist to the new double beam and ta-daaaa, You have a nice STRONG cavity to run your duct down and where ever.. (btw, now remove the shoring posts and ta-daaaa you are done)

Best of luck, Joey

Joey, I'm not a framer so I don't understand much of what you wrote. It sounds promising and I really appreciate that you took the time to share your expertise.

I'm going to look up all the terminology in your post and see if I can figure it out. Are there any pictures, diagrams or web links that might help me?

Thanks.