A faucet aerator is the small mesh screen on the tip of every kitchen and bathroom faucet — it mixes air with water for a smoother stream and acts as a debris filter for sediment from the supply line. When the aerator clogs (which happens every 1-3 years depending on water hardness), the faucet either dribbles, spits sideways, or shoots water unevenly. The fix is a 5-minute aerator clean or replacement.

This guide covers standard aerators (the ones you can unscrew from the faucet tip) and cache aerators (the ones recessed inside the faucet that need a special key).

Before you start

Three things to settle:

1. Aerator type. Standard: visible mesh-screen tip that unscrews by hand. Cache (concealed): recessed inside the faucet, needs a special small key (often included with newer faucets in a small plastic bag) to remove. If you don't have the key, inexpensive replacement keys are sold at hardware stores.

2. Thread direction. Most aerators thread male (with external threads on the aerator) or female (with internal threads). Newer faucets are dual-threaded — the aerator works either way. Check your existing aerator before buying replacement.

3. Flow rate. Aerators are rated in GPM (gallons per minute) or LPM (litres per minute). Standard kitchen aerators are 2.2 GPM (8.3 LPM). Bathroom aerators are 1.5 GPM (5.7 LPM). Low-flow aerators are 1.0 GPM (3.8 LPM) — water-saving option that may feel weak. Match or upgrade based on preference.

What you'll need

Tools

Adjustable wrench OR slip-joint pliers
Cleaning rag (to wrap around aerator for grip)
Toothbrush
Vinegar (for cleaning mineral deposits)
Small bowl
Cache aerator key (if applicable — verify in faucet documentation)

Materials

New aerator (matching size and thread direction)
Plumber's tape (Teflon, optional but recommended for re-seal)
White vinegar (for soaking)

Try cleaning before replacing

Most aerator problems are mineral buildup, not aerator failure. Soaking a clogged aerator in white vinegar for 1-2 hours dissolves mineral deposits and restores flow. Replacement is only needed if the screen is physically damaged or the housing is corroded.

Cleaning saves the cost of a new aerator and 5 minutes of measuring/buying. Try it first.

Step-by-step instructions

Identify the aerator type

Look at the faucet tip. If you see a mesh screen recessed inside or visible on the tip, that's the aerator.

Standard: visible mesh on the bottom of a threaded ring you can unscrew by hand. Cache: recessed flat on the faucet tip with no visible threads or grip points — needs a key.

Remove a standard aerator

Try by hand first — the aerator may twist off counterclockwise without tools.

If it's stuck, wrap the rag around the aerator (to protect chrome from wrench marks) and use slip-joint pliers or adjustable wrench. Turn counterclockwise.

Penetrating oil and a few minutes of waiting helps if the aerator is mineral-locked.

Remove a cache aerator

Insert the cache key (a small plastic tool with notches that match the aerator's slots) into the aerator from below.

Twist counterclockwise. The cache aerator threads out and drops into your hand.

If you don't have the key, hardware stores sell inexpensive universal keys that fit most cache aerator brands.

Try cleaning the aerator first

Soak the removed aerator in white vinegar for 1-2 hours. Mineral deposits dissolve into the vinegar.

After soaking, scrub with a toothbrush. Rinse thoroughly with clean water.

Inspect the screen — if it's still clogged or visibly damaged, replace. If clean, re-install.

Buy matching replacement (if needed)

Bring the old aerator to a hardware store. Match thread direction (male or female) and size (most kitchen aerators are 15/16 inch male thread; bathroom aerators are 55/64 inch female).

Confirm GPM rating — match or upgrade based on your preference.

Apply Teflon tape (optional)

For male-threaded aerators, wrap 2-3 turns of Teflon tape clockwise around the threads. The tape ensures a leak-free seal.

Skip the tape for female-threaded aerators — the seal happens at the rubber gasket, not the threads.

Hand-thread the new aerator

Thread the aerator onto the faucet by hand. The aerator should thread on smoothly with finger pressure.

If it binds within 1-2 turns, you've cross-threaded. Back off, realign, and start again. Cross-threading damages both faucet and aerator threads.

Snug with a wrench

Once hand-tight, snug another quarter turn with the rag-wrapped wrench. Don't over-tighten — the aerator's plastic body can crack.

Test for leaks and flow

Turn on the water. Watch the aerator-faucet joint for leaks. Drips at the threaded joint mean insufficient Teflon tape or a missing gasket — re-seat with more tape.

Test full flow at hot and cold. Stream should be smooth, not split or sideways. Spitting indicates the aerator's screen is blocked or the new aerator's flow rate is wrong.

Common mistakes that cost you

Replacing without cleaning first. Most aerator problems are mineral buildup. Vinegar soak is free and fixes 80% of cases.
Wrong thread direction. Male/female mismatch means the new aerator doesn't thread on. Always verify before buying.
Cross-threading. If the aerator binds within 1-2 turns, back off and realign. Forcing damages threads on both pieces.
Over-tightening. Cracks the plastic aerator body. Hand-tight plus a quarter turn is enough.
Skipping Teflon tape on male threads. Drips at the joint. A cheap roll of tape prevents this.

Frequently asked questions

How often should I clean the aerator?

Every 6-12 months in hard water areas (typical for many Ottawa neighbourhoods on well water or with municipal water that's mineral-rich), every 12-24 months in soft water areas.

Symptoms: weak flow, splitting stream, water spraying sideways. Don't wait until the faucet barely works — periodic cleaning maintains performance.

Can I install a low-flow aerator?

Yes — and you'll save water/money. Low-flow aerators (1.0 GPM) feel slightly weaker but are adequate for most uses. high-efficiency aerators meet Canadian water-efficiency standards.

If your existing faucet feels strong, the new low-flow aerator may feel weak by comparison. Try one and see; most retailers allow returns.

Why does the new aerator leak?

Either insufficient Teflon tape (for male threads) or a missing/damaged rubber gasket (for female threads). Re-install with proper sealing.

Sometimes the aerator's threads are slightly off-spec. Try a different brand if the same model continues to leak.

When to call us instead

If your faucet has chronic flow issues that aerator cleaning doesn't fix, the problem may be in the supply lines or the faucet cartridge itself. We do plumbing diagnostics as part of bathroom or kitchen renovations.

Book a free 60-minute site visit →

Related Ottawa services

If you have ongoing plumbing issues, our bathroom and kitchen renovation teams handle plumbing fixtures and supply work as part of larger scopes. Book a free 60-minute consultation.