When you are remodeling your bathroom there are times when you want to relocate the fixtures to provide better access. Toilet flanges are the attachment of the waste line to the removable toilet.
Basically a large 3 to 4 inch pipe used to carry waste out of your home is positioned under your bathroom. To connect your toilet, tub and sink to this line a smaller line will pass through the floor of the bathroom. In the case of your sink and tub additional pipes are connected to route to the fixtures but because the toilet mounts to the floor of the bathroom a flange is placed on the floor allowing the waste pipe to be attached from below and the toilet to be bolted to the flange for good stability.
The flange if PVC is glued to the waste pipe and if cast iron it is attached with lead or oakum and another sealer.
Between the flange which is mounted on the floor of the bathroom and the toilet is a thick wax ring which makes a good seal. Most wax rings are 1 inch thick but they can be thicker if necessary and include inserts to provide a good seal between the bottom of the toilet and the waste pipe flange.
Normally if you are simply upgrading your fixtures such as your bathtub, toilet and sink you will not need to do major relocation of the supply and waste pipes but if you are expanding into an adjacent closet or turning a half bath into a full bathroom you will definitely need to relocate your plumbing.
Before you go any further it is important to understand how plumbing works and if you need permits to perform the work. If you are in a single family home and are adjusting the position of the toilet flange to fit a new toilet that is in the approximate same location then you do not normally need to apply for a permit. If you are removing walls and relocating plumbing pipes more then about a foot in any direction or if you are cutting into any structural wood framing of your home then you most likely do need a permit and an inspection.
If you are doing the work yourself your local building official will normally work with you to reduce the paperwork and necessity of inspections however if you are hiring a contractor this is important to remember because unpermitted work in your home that is performed by anyone other then the home owner will likely mean your home owners insurance will not cover any damage now or in the future.
Ok so lets move on to what is required to move your toilet flange so you can attach your toilet in its new location.
Moving your Toilet Waste Flange
The first thing you need to do is remove your toilet.
- Turn off the water supply line to the toilet and flush the toilet empty.
- Remove any leftover water in the tank or toilet bowl with a sponge
- Place a large piece of plastic down where you will place the toilet while working it will still have residual water in it and it will leak.
- Remove the flange caps then unbolt the toilet from the floor flange.
- Pull the toilet straight up slowly, the wax ring will act like glue so it will take some effort.
- Using a drywall spatula remove the wax ring from the bottom of the toilet and the waste flange this is messy work have a trashcan and paper towels ready.
Inspect the flange to see what type of pipe you will be working with. If your home is less then 10 years old or if it has had a recent remodel then it should be PVC Pipe this is the easiest to work with.. if it is a metal flange inspect the inside of the pipe to verify that the pipe is actually cast iron because some PVC flanges come with a steel ring.
Repositioning the Toilet Waste Pipe
You will now need to decide if you will be better off re-plumbing the waste lines for the entire bathroom or if you only need to reposition and patch the toilet connection.
If all of the other fixtures in the bathroom are remaining in the same location and you only need to move the waste pipe for the toilet a few inches you will be able to install a union and patch the connection to the toilet flange.
If you are repositioning waste lines for all of your fixtures then you should consider re-plumbing the entire bathroom waste system especially if you have cast iron. Cast iron is difficult to work with because it is brittle and hard to cut. If you can attach PVC to the main waste line and then install PVC pipe for all of your fixtures this may be easier then patching even one cast iron connection.
The problem is most home owners do not have the tools or skills to make a really good cast iron to cast iron connection. If you are patching new PVC to old Cast Iron you can use a Rubber Transition that is similar to a rubber radiator hose but doing so may mean problems in the future.
You will need to gain access to the waste lines from below the bathroom.
This means that you will need to work from your crawl space under your home or basement OR remove the drywall on the ceiling in the room below the bathroom. You may also need to remove adjacent wall drywall to make your transition connection.
Once you have decided on how much work will be needed to remove the portion of pipe that will be replaced.
For PVC you can use a reciprocating saw to cut the plastic pipe.
Working in the room below cut the waste line near the original toilet flange then go upstairs and remove the flange from the bathroom side of the floor there may be attachment screws you need to remove.
You will have the option of capping this waste line with a PVC end Cap which you glue on if you are moving the toilet a few feet or adding on pipe if you only need to move the flange a few inches.
Once the new connections are made below you will need a helper to install the flange while you support the pipe below. When gluing PVC pipe it will tend to want to come apart so a helper is good but if you don’t have one you can screw the new flange in place then force the pipe into the flange from below.
Checking Your Work
A professional plumber that is installing a new waste system will pump air into the waste lines to tell if there are any leaks. Unfortunately once the system is operational doing a leak test becomes more difficult.
I would suggest that you operate the bathroom toilet for at least a 2 days before you replace the drywall on the ceiling below the bathroom. You want to make sure that you flush the toilet while the bathtub and sink are draining to make sure that there are no problems.
If you are working on a remodeling of the whole bathroom this should not be a serious inconvenience to leave the drywall off for a day or two just to make sure no leaks occur and you will have lots of other work to do while you wait and test.