Most leaky faucets can be fixed in under an hour by replacing worn internal parts—typically costing $10-50 in parts versus $150-$330 for a plumber. Identify your faucet type first (compression, ball, cartridge, or ceramic disc), turn off water under the sink, then replace the worn components.
A dripping faucet wastes up to 3,000 gallons per year and the fix is usually straightforward. The key is identifying your faucet type—each requires different parts and a slightly different approach.
What You’ll Need
Tools:
- Adjustable wrench
- Allen wrench set (1/8” most common)
- Phillips and flathead screwdrivers
- Needle-nose pliers
- Basin wrench (for tight spaces)
Materials:
- Replacement cartridge or repair kit: $10-50
- Plumber’s grease
- Towel and flashlight
Identify Your Faucet Type
| Type | How to Identify | Common Failed Parts |
|---|---|---|
| Compression | Two handles that twist; must tighten fully to stop water | Seat washers, O-rings |
| Ball | Single handle moving in all directions | Rubber seats, springs, O-rings |
| Cartridge | One or two handles with smooth quarter-turn | O-rings, entire cartridge |
| Ceramic Disc | Single lever with wide cylindrical body | Neoprene seals |
Take your old cartridge to the hardware store for an exact match. Faucet parts are NOT interchangeable between brands. Common Moen cartridges: 1225 (single-handle), 1222 (Posi-Temp shower). Common Delta: 1300/1400/1700 series.
Step-by-Step: Cartridge Faucet Repair (Most Common)
Step 1: Shut Off Water Supply
- Locate oval shut-off valves under the sink
- Turn both clockwise until fully closed
- Turn on faucet handles to release residual water
- Confirm water is completely off
Step 2: Prepare Work Area
- Close the drain with a stopper or rag (small parts fall easily)
- Place a towel in the sink to protect the surface
Step 3: Remove the Handle
- Pry off decorative cap (may show H/C indicator) with flathead screwdriver
- Remove exposed screw—typically Phillips or 1/8” Allen
- Pull handle straight up off cartridge stem
- If stuck, apply penetrating oil and wiggle gently
Step 4: Access the Cartridge
- Remove escutcheon or trim ring
- Unscrew bonnet/retaining nut counterclockwise with adjustable wrench
- Look for retaining clip (brass or plastic horseshoe shape)
- Remove clip with needle-nose pliers
Step 5: Remove Old Cartridge
- Take a photo to note cartridge orientation (position of tabs/notches)
- Pull cartridge straight up—grip stem with pliers if needed
- For stuck Moen 1225: use a cartridge puller tool
Step 6: Install New Cartridge
- If only O-rings are worn, replace them with exact-size matches
- Apply thin coat of plumber’s grease to new O-rings and cartridge body
- Align cartridge tabs/notches with corresponding slots in faucet body
- Push straight down until fully seated
Step 7: Reassemble
- Replace retaining clip (push until tips visible at bottom)
- Hand-tighten retaining nut, then 1/4 turn with wrench—avoid overtightening
- Replace handle, trim ring, and decorative cap
Step 8: Test
- Slowly turn on water supply valves
- Check for leaks at all connection points
- Run water several minutes to flush debris
Cost Comparison
| Repair Type | DIY Cost | Plumber Cost |
|---|---|---|
| Washer/O-ring | $3-10 | $60-150 |
| Cartridge replacement | $10-40 | $150-270 |
| Complete repair kit | $15-50 | $200-330 |
When to Call a Pro
Call a plumber if:
- Faucet is over 15-20 years old (replacement more cost-effective)
- Extensive corrosion or rust on faucet body
- Cartridge is completely stuck and puller tool fails
- Shut-off valves don’t work or are leaking
- Water damage visible behind walls or under cabinet
- Faucet body is cracked
- Repair costs exceed 50% of new faucet cost
Common Mistakes to Avoid
- Not identifying faucet type first — Each type requires different parts and approach
- Forgetting to plug the drain — Small screws are easily lost
- Not photographing disassembly — Critical for correct reassembly
- Buying wrong parts — Take old cartridge to store; parts aren’t interchangeable between brands
- Overtightening connections — Causes cracked parts and stripped threads
- Skipping plumber’s grease — Lubricates O-rings and ensures proper seal
- Not replacing seats and springs — These $3-5 parts often cause continued leaks
Frequently Asked Questions
How do I know what type of faucet I have?
Compression faucets have two handles that must be tightened to stop water. Ball faucets have a single handle that moves in all directions. Cartridge faucets have one or two handles with smooth quarter-turn operation. Ceramic disc faucets have a single lever with a wide cylindrical body.
What size Allen wrench do I need for faucet repair?
Most faucet handle screws require a 1/8-inch or 3/32-inch Allen wrench. Keep a full Allen wrench set handy as sizes vary by brand. The screw is typically hidden under a decorative cap marked H or C.
Should I repair or replace an old faucet?
If your faucet is over 15-20 years old, replacement is often more cost-effective. Also replace if you see extensive corrosion, the body is cracked, or repair costs exceed 50% of a new faucet price. Parts for discontinued models may be unavailable.
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- Toilet Keeps Running — Fix running toilet issues