
How to Replace a Bathtub Drain Flange
About This Project
This guide provides verbose, step-by-step instructions for removing an old, corroded, or leaking bathtub drain flange and installing a new one. The process involves removing the stopper, unscrewing the old flange using a specialized tool, cleaning the tub surface, and installing the new flange with a fresh seal of plumber's putty or silicone.
Best for advanced DIYers and professionals with basic plumbing knowledge and familiarity with power tools.
Tools & Materials

Towel

OdoBan 1 Gal. Shower, Tub and Tile Cleaner Refill (Ready-To-Use), Powerful Foaming Bathroom Cleaner 9353C61-G

Mr. Clean Extra Durable Magic Erasers Multi-Purpose Cleaning Sponge (10 Count) 003700069525

Rubber-Cal "Paw-Grip" Red 34 in. x 60 in. 100% Nitrile Rubber Non-Slip Matting 03_183_WRE_05

Klein Tools 1/4 in. Cabinet-Tip Flat Head Screwdriver with 10 in. Heavy-Duty Round Shank 605-10

Rag

Towel
Absorbs moisture and dries surfaces.

OdoBan 1 Gal. Shower, Tub and Tile Cleaner Refill (Ready-To-Use), Powerful Foaming Bathroom Cleaner 9353C61-G
OdoBan Shower, Tub and Tile Cleaner is a multi-purpose, multi-surface foaming bathroom cleaner. Powerful foaming spray cuts through tough bathroom stains and gunk. Removes soap scum, dirt, calcium, lime

Mr. Clean Extra Durable Magic Erasers Multi-Purpose Cleaning Sponge (10 Count) 003700069525
Mr. Clean Magic Eraser extra-Durable scrubber is 4x Stronger with Durafoam. The cleaning micro-scrubbers reach into the surface grooves, lifting away built up dirt and grime. Use it all around the house

Rubber-Cal "Paw-Grip" Red 34 in. x 60 in. 100% Nitrile Rubber Non-Slip Matting 03_183_WRE_05
Rubber-Cal's "Paw-Grip" Non-Slip Mat is a high-quality flooring option sold at a width of 34 inches and a thickness of 3/8-inches, with varying lengths. Along with excellent traction, this flooring offers

Klein Tools 1/4 in. Cabinet-Tip Flat Head Screwdriver with 10 in. Heavy-Duty Round Shank 605-10
The Klein Tools 1/4-Inch (6 mm) Cabinet Tip Screwdriver 10-Inch (254 mm) with heavy-duty round-shank has a narrow cabinet tip that permits blade access where space is limited. It meets or exceeds applicable

Rag
Handy for cleaning or wiping tasks.
Steps
Prepare the Work Area
10 minsBegin by thoroughly cleaning the bathtub, especially around the drain area, to remove any soap scum, grime, or residue. Once clean and dry, place an old towel or a non-slip rubber mat in the bottom of the tub. This crucial step protects the tub's delicate surface from accidental scratches or dings from your tools during the replacement process. Gather all the tools and materials you will need and place them on the towel for easy access.
Remove the Existing Drain Stopper
5 minsFor the assumed push-and-pull stopper, ensure it is in the open ('up') position. Firmly grip the round knob on top of the stopper and rotate it counter-clockwise to unscrew it. If it's tight, you can wrap a rag around it and use pliers for a better grip. Once the knob is off, you will see a brass post with a slot in its center, which is threaded into the flange's crossbars. Use a large flathead screwdriver or the tips of your pliers to engage this slot and unscrew the post by turning it counter-clockwise until it's completely removed.
Unscrew the Old Drain Flange
15 minsThis is often the most challenging part of the job. Insert your drain removal tool, such as a drain key, into the drain opening. Ensure the tool's prongs fit securely into the crossbars of the flange. To gain leverage, slide the long handle of a pair of pliers or the shaft of a large screwdriver through the hole(s) at the top of the drain removal tool, creating a T-handle. Apply firm, steady downward pressure while turning the handle counter-clockwise. You may feel a 'pop' as the old putty seal breaks. Continue turning until the old drain flange is completely unthreaded from the drain shoe below.
Clean the Drain Opening
10 minsWith the old flange removed, you'll see a ring of old, hardened plumber's putty. Use a plastic putty knife or the edge of an old credit card to carefully scrape all of this old putty off the surface of the tub around the drain opening. Avoid using metal scrapers which can easily scratch the tub finish. Once the bulk is removed, use a clean rag dampened with denatured alcohol or mineral spirits to wipe away any remaining oily residue. Use a small wire brush to gently clean the threads inside the drain shoe to ensure the new flange can be installed smoothly without cross-threading.
Install the New Drain Flange
10 minsTake a generous amount of fresh plumber's putty and warm it in your hands. Roll it out into a uniform, snake-like rope about 1/4-inch to 3/8-inch thick. Press this rope firmly and evenly onto the underside of the new drain flange's lip. Some tub materials like acrylic can be stained by plumber's putty, in which case a bead of 100% silicone sealant is a better choice. Carefully position the new flange over the drain opening and begin turning it clockwise by hand. Ensure it is threading in straight and not cross-threading. Hand-tighten it as much as possible, then use your drain removal tool to give it a final quarter to half turn to snug it down firmly. This action will squeeze out the excess putty, creating a perfect watertight seal.
Final Cleanup and Stopper Reinstallation
10 minsOnce the flange is tightened, a ring of excess plumber's putty will have squeezed out. Use your finger or the plastic putty knife to neatly remove this excess putty. Follow up with a soft, clean rag to wipe away any remaining residue for a clean, professional finish. Now, reinstall the stopper mechanism. Screw the central brass post back into the crossbars, and then screw the stopper knob onto the post. Adjust the post's height so that when the stopper is closed, it sits flush and creates a good seal, and when open, it allows water to drain freely.
Test for Leaks
15 minsThe final step is to test your work. Close the drain stopper and fill the tub with several inches of water. Let the water sit for at least 10-15 minutes. While it's sitting, if you have access from below, check the drain assembly for any signs of drips. If you don't have access, keep a close eye on the ceiling of the room directly below the bathtub for any new water stains. After waiting, open the drain and let all the water drain out, again checking for any leaks as the water flows through the pipe. If no leaks are found, the job is complete.
Common Problems
Uneven tightening causes a leaky seal.
Solution: Tighten the three screws in an alternating pattern to ensure even pressure and a good seal.
Discoloration of light-colored porcelain sinks around the drain flange.
Solution: Using a stain-free plumber's putty is recommended, especially for light-colored porcelain sinks, to prevent discoloration over time.
Do not use the hard plastic washer under the flange if using plumber's putty; the putty itself creates the seal.
Solution: To avoid this issue: Be mindful of this warning and take appropriate precautions.
A dirty flange surface will lead to a leaky drain.
Solution: A clean surface is critical for a good, leak-proof seal.
Future bathtub drain flange removal becomes incredibly difficult if silicone caulk is used instead of plumber's putty.
Solution: Do not use silicone caulk in place of plumber's putty, as it can make future removal extremely difficult.
The video incorrectly shows the use of caulk. You must use plumber's putty to create a proper, lasting, and removable seal.
Solution: To avoid this issue: Be mindful of this warning and take appropriate precautions.
Attempting to move a bathtub alone can lead to injury or damage.
Solution: It is recommended that the bathtub is carried by a minimum of two people.
Frequently Asked Questions
What if my old drain flange is severely corroded or stuck and won't unscrew?
If the old flange is stubborn, try applying penetrating oil and letting it soak for a while to help loosen rust. The specialized Husky Tub Drain Removal Tool is designed for maximum grip, but for extreme cases, you might need to carefully cut the crossbars from the inside with a reciprocating saw to collapse the flange and remove it.
Do I have to use plumber's putty, or can I use silicone sealant for the new flange?
While the guide suggests plumber's putty, clear silicone sealant like DAP Silicone Max is an excellent alternative for a more permanent, waterproof seal that resists degradation over time. Ensure the tub surface is completely dry and clean before applying silicone, as it requires a perfectly dry surface to cure properly. Plumber's putty is generally easier for beginners to work with and remove if necessary.
How can I ensure a watertight seal and prevent future leaks after installing the new flange?
To ensure a watertight seal, apply an even, generous bead of plumber's putty or silicone around the underside lip of the new flange before inserting it into the drain opening. When tightening the flange, make sure it's snug, but avoid over-tightening which can distort the seal or even crack the tub. Always conduct the leak test by filling the tub and watching the drain connection underneath for at least 15-30 minutes.
Is the specified "Husky Tub Drain Removal Tool" essential, or are there alternatives if I don't have it?
The Husky Tub Drain Removal Tool is highly recommended for this project as it provides the best leverage and reduces the risk of damaging the drain. While some people attempt to use pliers with a rag or a screwdriver across the crossbars, these methods can easily strip the drain or not provide enough torque. Investing in the correct tool is crucial for a successful, frustration-free installation.
The project estimates 3 hours; is this realistic for a beginner, and what might make it take longer?
Yes, 3 hours is a realistic estimate for a beginner under normal circumstances. The project can take longer if the old drain flange is heavily corroded, making removal difficult, or if extensive cleaning of the drain opening is required. First-time DIYers might also spend extra time preparing the work area, reading instructions, and ensuring all materials are gathered.
What should I do if, after installing the new flange and testing, I still notice a small leak?
If you detect a leak, first ensure the drain shoe nut underneath the tub is securely tightened – sometimes this is the culprit. If the leak persists, carefully remove the new drain flange, clean off all the old sealant or putty, and reapply a fresh, more generous bead around the flange lip, ensuring complete coverage. Reinstall the flange, tighten, and retest thoroughly.
What safety precautions should I take, especially when dealing with old drains or cleaning products?
Always wear appropriate personal protective equipment, such as safety glasses and gloves, especially when cleaning or dealing with old, potentially sharp metal components. Ensure good ventilation if using strong cleaning solutions like OdoBan or similar products. While not typically necessary for this specific repair, it's a good general practice to know how to turn off the water supply to the tub.






