How to clean paint brushes (and get rid of the dirty water)

First: get the paint out before you wash

The less paint on the brush, the less dirty water or thinner you’ll have to deal with. Sherwin-Williams says to clean brushes and rollers as soon as you can after painting, and to remove as much paint as possible first.

• Scrape the brush against the inside rim of the can, or squeeze the roller.
• Brush out the extra paint onto newspaper or scrap cardboard.
• Use a scraper or a brush-and-roller spinner if you have one.
• Scrape leftover paint out of the tray and back into the can. Alachua County, Florida, says scraping cans with a rubber spatula can save up to 9% of your paint.

How do you clean latex paint brushes?

1. Fill a bucket with warm, soapy water. Sherwin-Williams recommends soap and water for latex and acrylic house paint.
2. Work the bristles in the water and swish them. Change to fresh water as it gets cloudy.
3. Rinse under running water, holding the brush bristles down so water and paint don’t run into the metal band (the ferrule).
4. Press out the water with a paper towel or cloth.
5. Let it dry, then store it in a plastic bag or its original cover so it keeps its shape.

Where does latex paint water go?

If your home is on city sewer, pour latex rinse water into an indoor sink or toilet. Indoor drains go to a treatment plant. The Sacramento Stormwater Quality Partnership says wash water from cleaning latex brushes, rollers and tools may go to the sanitary sewer. Alachua County says the same.

Never pour it in the street, a gutter, a storm drain or a creek. Storm drains usually carry water straight to local creeks with no treatment. Sacramento notes that even latex paint has chemicals that harm fish and other water life.

Wash water is not the same as leftover paint. Sacramento says not to pour leftover paint into any drain. Scrape buckets and trays out first, and deal with the extra paint as leftover paint.

What if you have a septic system?

Be careful. EPA’s SepticSmart program says not to pour paints and solvents down your sink, because they can clog or harm your system. Sacramento’s guide warns that paint and paint waste can contaminate soil and groundwater if they go into a septic tank.

Local advice differs on what to do instead. Alachua County says septic users may wash latex brushes in a grassy area away from water bodies. Ask your county health or septic office before you do that.

Here are better options if you’re on septic:

• Wipe brushes very well first so there’s less paint in the water.
• Let the rinse water sit in a bucket until the paint settles. Pour off the clearer water, and let the sludge dry out.
• Use a flocculation kit or recipe to pull the paint solids out of the water. Golden Artist Colors publishes a method for water-based paint (see our acrylic paint guide).
• Clean up somewhere that has city sewer, as Sacramento suggests for job sites without sewer.

How do you clean oil-based paint brushes?

1. Work outside or in a room with lots of fresh air. Keep flames, pilot lights and sparks away.
2. Pour a few inches of mineral spirits or paint thinner into a metal container. Use the solvent the paint label names.
3. Work the brush in the thinner, then press it out. Repeat in a second, cleaner batch if needed.
4. Sherwin-Williams says to finish by rinsing under running water, bristles down.
5. Lay the brush flat to dry, then wrap it to keep its shape.

How do you reuse paint thinner?

You don’t need to throw dirty thinner away after one use. Both Sherwin-Williams and Sacramento’s guide describe the same method.

1. Pour the dirty thinner into a container you can seal, and label it.
2. Let it sit, closed, until the paint sinks to the bottom.
3. Pour the clear thinner off the top into its original container to reuse. Alachua County says you can also filter out particles with a reusable wire screen.
4. Deal with the sludge left at the bottom. Sacramento and Alachua County say to take the unusable part to household hazardous waste. Sherwin-Williams says to let solids air-dry away from children, pets and flames, then put the container in the trash. Check which your area allows.

Where does dirty thinner go?

Never pour thinner or mineral spirits down a drain, on the ground or into a storm drain. PaintCare drop-off sites don’t take thinners or solvents, even in PaintCare states. Take them to a household hazardous waste site or collection event. Our paint thinner guide covers this in detail.

Safety while you clean

• Work with thinner outside or with windows open. Sherwin-Williams says to always use a well-ventilated area.
• No smoking, flames or pilot lights nearby. NFPA lists paint thinner as a combustible liquid.
• Wear gloves. Minwax’s safety sheet for its oil-based stain, for example, says to wear protective gloves and eye protection.
• Keep buckets of thinner and paint water away from kids and pets, and never leave them uncovered.
• Keep thinner in its original, labeled container with the cap on tight. NFPA says never to store these liquids in glass.

Quick comparison

Rollers, trays and when to toss a brush

Roller covers hold a lot of paint. Scrape them hard before washing, or let them dry and throw them out if they’re cheap. Sacramento suggests disposable rollers and trays for oil-based paint so you can avoid solvents: let them dry, then trash them.

A brush with paint dried deep in the ferrule may never work well again. Let any paint on it harden fully, then throw it away.

Painting a lot?

Contractors at job sites should use the cleanup and disposal spots the property owner or site boss names, Sacramento says. If there’s no sewer on site, clean up somewhere that has it. Businesses often can’t use household hazardous waste sites; see our guide for contractors.