Install New Wax Ring and Reinstall Toilet — Reinstall the Toilet
Part of project
How to Replace a Cast Iron Toilet Flange with PVC · Step 9 of 10
In this video
Once the flange is at the correct height, install a new wax ring. Place the wax ring directly on top of the new flange, centered over the drain opening. Carefully lift the toilet, align the holes in its base with the new closet bolts sticking up from the flange, and lower it straight down. Press down firmly to compress the wax ring and create a seal. Place the washers and nuts on the closet bolts and tighten them down evenly, alternating from side to side. Be careful not to overtighten, as this can crack the porcelain base of the toilet. Reconnect the water supply, turn the water on, and check for leaks.
Goal: Toilet Repair
- If the flange is below the floor level, you might need to use two wax rings, but never use three. The proper fix is to raise the flange.
- Tighten the closet bolts gradually and evenly. The toilet should be snug and not rock, but overtightening will crack the base.
Used in this video
- Adjustable Wrench (Adjustable Wrench Size: Medium (8)) — Tightening the nuts on the closet bolts.
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FAQs
How difficult is replacing a cast iron toilet flange with PVC, and how long should I expect it to take?
This project is rated as intermediate. While it doesn't require specialized plumbing skills, removing the old cast iron and lead/oakum seal can be physically demanding and time-consuming. Expect it to take anywhere from half a day to a full day, especially if you encounter unexpected issues like a stubborn old flange.
What specialized tools are absolutely essential for removing the old cast iron flange and its lead/oakum seal?
Beyond basic household tools, you'll definitely need a cold chisel and a hammer for breaking up the old cast iron and carefully removing the lead/oakum seal. A shop vacuum is also crucial for quickly cleaning up debris and ensuring the cast iron pipe is spotless before installing the new flange.
What are the most important safety precautions I should take when demolishing the old cast iron flange and seal?
Always wear heavy-duty safety glasses to protect against flying fragments and a respirator (like the Honeywell R95) to avoid inhaling dust and potential lead particles from the old seal. Heavy-duty gloves are also essential to protect your hands from sharp edges and the demolition tools.
What's a common mistake when installing the new PVC compression flange, and how can I avoid it?
A common mistake is not thoroughly cleaning and deburring the inside of the cast iron pipe after removing the old flange. Any rough edges, rust, or debris can compromise the compression seal of the new PVC flange, leading to leaks. Ensure the pipe's interior is smooth and completely clean for a watertight fit.
Install New Wax Ring and Reinstall Toilet — Reinstall the Toilet
Part of project
How to Replace a Cast Iron Toilet Flange with PVC · Step 9 of 10
In this video
Once the flange is at the correct height, install a new wax ring. Place the wax ring directly on top of the new flange, centered over the drain opening. Carefully lift the toilet, align the holes in its base with the new closet bolts sticking up from the flange, and lower it straight down. Press down firmly to compress the wax ring and create a seal. Place the washers and nuts on the closet bolts and tighten them down evenly, alternating from side to side. Be careful not to overtighten, as this can crack the porcelain base of the toilet. Reconnect the water supply, turn the water on, and check for leaks.
Goal: Toilet Repair
- If the flange is below the floor level, you might need to use two wax rings, but never use three. The proper fix is to raise the flange.
- Tighten the closet bolts gradually and evenly. The toilet should be snug and not rock, but overtightening will crack the base.
Used in this video
- Adjustable Wrench (Adjustable Wrench Size: Medium (8)) — Tightening the nuts on the closet bolts.
Frequently Asked Questions
How difficult is replacing a cast iron toilet flange with PVC, and how long should I expect it to take?
This project is rated as intermediate. While it doesn't require specialized plumbing skills, removing the old cast iron and lead/oakum seal can be physically demanding and time-consuming. Expect it to take anywhere from half a day to a full day, especially if you encounter unexpected issues like a stubborn old flange.
What specialized tools are absolutely essential for removing the old cast iron flange and its lead/oakum seal?
Beyond basic household tools, you'll definitely need a cold chisel and a hammer for breaking up the old cast iron and carefully removing the lead/oakum seal. A shop vacuum is also crucial for quickly cleaning up debris and ensuring the cast iron pipe is spotless before installing the new flange.
What are the most important safety precautions I should take when demolishing the old cast iron flange and seal?
Always wear heavy-duty safety glasses to protect against flying fragments and a respirator (like the Honeywell R95) to avoid inhaling dust and potential lead particles from the old seal. Heavy-duty gloves are also essential to protect your hands from sharp edges and the demolition tools.
What's a common mistake when installing the new PVC compression flange, and how can I avoid it?
A common mistake is not thoroughly cleaning and deburring the inside of the cast iron pipe after removing the old flange. Any rough edges, rust, or debris can compromise the compression seal of the new PVC flange, leading to leaks. Ensure the pipe's interior is smooth and completely clean for a watertight fit.