Shower Install -- How Downsize Existing Drain Hole Siize

Users who are viewing this thread

unionmaid

New Member
Messages
8
Reaction score
0
Points
1
Location
Johnstown, OH
We're installing a cement shower pan in our upstairs bathroom.

The existing drain hole in the sub floor is too big -- 7.5" diameter.

Our abs Oatey drain requires only a 4.5" hole.

The sub floor is made of 3/4 plywood over joists.

Any recommendations?

TIA
 

VolsMan

New Member
Messages
2
Reaction score
0
Points
0
Location
West TN
Hello,

One way I would consider is to set the blade depth of circular saw to cut 3\4", remove the appropriate nails in the sub floor and cut a 16" square of the subfloor(center of one floor joist to center of other floor joist) that incorparates the 7.5" diameter existing hole. Properly replace with new piece of 3\4" and re-cut the hole the desired size.

Bubba
 

Jadnashua

Retired Defense Industry Engineer xxx
Messages
32,771
Reaction score
1,191
Points
113
Location
New England
That's a reasonable approach, but I'd also consider putting in some blocking on the cross joist ends of the patch otherwise, it will not be as sturdy, which is highly desireable under a shower pan. Check out www.johnbridge.com for help on tiling. For maximum strength, a patch should bridge two joist bays and anchor to three joists. If you put blocking in, it's almost as strong.
 

unionmaid

New Member
Messages
8
Reaction score
0
Points
1
Location
Johnstown, OH
Thank you Jim and Bubba. We have been reading a lot on the johnbridge site and that has been helpful. We got the shower floor done by laying down another sheet of 3/4" plywood. Mortar shower pan is next.
 
Top
Hey, wait a minute.

This is awkward, but...

It looks like you're using an ad blocker. We get it, but (1) terrylove.com can't live without ads, and (2) ad blockers can cause issues with videos and comments. If you'd like to support the site, please allow ads.

If any particular ad is your REASON for blocking ads, please let us know. We might be able to do something about it. Thanks.
I've Disabled AdBlock    No Thanks