I've had a situation where a home installed toilet with a 15" offset from the back wall. The typical offset for most residential toilets is 12 inches. As a result, the toilet is 4 inches behind the tank. It looks like it's trying to get involved in the restroom instead of sitting quietly until needed. This seems like a hopeless situation. I mean, who wants to completely remove and cut out a new toilet drain? In fact, you can use a simple solution to solve this problem. We show you how to install an offset toilet flange to place the toilet closer or farther from the wall.
Shopping at your local home improvement store, you'll find something called a toilet offset flange. This product will allow you to add approximately 2 inches of extra distance in any direction over your existing toilet waste pipe. It fits both 3" and 4" sewer pipes. Outside diameter (OD) fits inside of 4 inch pipe. The inside diameter (ID) allows you to mount it on 3" PVC pipe. Typically offset toilet flanges cost less than $15.
Here's what an offset toilet flange looks like:
How to Install an Offset Toilet Flange
As you can see, offset toilet flanges are primarily made of PVC with a metal or PVC flange ring on top that can be rotated under the toilet to center the bolt as needed. This also gives you more advantages. The toilet can be moved in any direction – forward, backward, even diagonally if desired.
Consumables (based on 4″ PVC sewer pipe, adjust 3″ accordingly):
- Offset Toilet Flange
- 4″ Schedule 40 PVC Pipe
- 4″ Schedule 40 PVC Coupler
- One-step PVC cement
- Wax Rings and Bolts (Double Thick Kit)
- Great Stuff Expanding Foam for Windows and Doors
required tools
- reciprocating saw
- cordless drill
- Dremel or other rotary tool with cutting blade
- adjustable wrench
- Bolt cutters or metal saw (an oscillating multi-tool can be used)
We're going to move the toilet straight back. To that end, the following steps explain how to install an offset toilet flange for this purpose:
demolition of existing toilets
Use a spanner wrench to remove the nuts on the retaining bolts and remove the toilet from the existing flange.
remove old wax ring
Remove and dispose of the old wax ring. Clean the toilet base in preparation for a new wax ring and flange.
plug waste hole
Tuck a thick rag or disposable towel into the existing toilet hole. This stops sewer gas from escaping into the room. You will thank us later.
plan your health
Plan how to install the new offset flange. The base of the offset toilet flange typically fits over 3 inches of PVC pipe or within 4 inches of pipe. Do your best to ensure that waste flows smoothly into the sewer line. You don't want seams or anything that could cause backups or restrict… waste flow.
go out with the old
Remove the screws holding the old toilet flange to the floor and remove the old toilet flange. Use a Dremel or similar tool to cut the pipe from the inside to connect the new pipe. If you have tight spaces, you can use a reciprocating saw to cut the pipe from below. You want to end up with a pipe that can be connected to the new offset flange. Be sure to measure the depth in order to use the coupler successfully. In the worst case, you may need to use rubber boots to attach the two new parts together.
Finally, remove and discard the old toilet flange.
dig out the floor to make room
Using a reciprocating saw, cut away where the offset flange is needed to set the toilet further back against the wall. This is best done with wood or with a demolition blade. You may need to angle the blade slightly to avoid cutting too much material. Just keep in mind that you'll want the new flange to fit snugly so you have enough wood to hold it securely to the floor.

test your new body
Dry install the new offset flange until you are satisfied with its fit.
Installing a New Offset Toilet Flange
Apply a generous amount of one-shot PVC cement to the ends of the pipe and offset flanges and install them together. Alternatively, if you find that you need to use a rubber boot, slip the boot over both pieces and secure with a flathead screwdriver. Usually only bootable in a crawl space environment as you need access to make it work.

In our particular case we also had to cut out some extra floor tiles. For this, we use an angle grinder with a continuous diamond cut-off wheel. It allowed us to make the proper arc cut so we could mount the new toilet flange directly to the floor.
fill in the blanks
If there is any space in the front of the new offset flange (and there should be, if you did it right), fill it with Great Stuff Window & Door expanding foam. Be careful so you don't have to trim it too much. If you happen to overdo it, just let it dry and smooth it out with a razor blade or something with a serrated blade. The toilet should cover the exposed area you just filled.
installation hardware
Insert new hardware bolts into the offset flange. This will anchor the toilet to the flange and floor so it won't move.
Install new wax ring
Place the double thick wax ring over the flange, wax side up, with the short side inserted into the flange opening. We always recommend double thick wax rings because we have installed too many toilets with gaps that exceed the depth of a basic wax ring. You can hardly expire wax rings.
relocate the toilet
When replacing the toilet, carefully align the holes in the base with the bolts protruding from the flange of the newly offset toilet. This step is much easier if you have two, since the toilet itself tends to block your view of the flange bolts. Operate the toilet down until it lies flat on the floor. Secure the bolts with the washers and nuts provided.
As a final step, secure the bolts to length with a pair of bolt cutters. You can also use metal blades on oscillating multi-tools or reciprocating saws. You can then place plastic covers (if you have one) to cover the bolts.
in conclusion
Everything here is its own. Now you can "enjoy" your new moving toilet as if it was installed correctly to begin with. This is a relatively easy project to undertake. Knowing how to install an offset toilet flange and doing a little pre-planning can often make the difference between an easy or a tough day for you.