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The Painter's DilemmaIs it worth it to wash out my paintbrushes?

By Nina Shen RastogiPosted Tuesday, July 7, 2009, at 9:32 AM ET

I'm planning to spend the weekend painting my house, and I'm not sure what to do with the brushes and rollers when I'm done. It took gallons of water to clean them the last time we painted, but maybe that's better than using the cheap, disposable kind?

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It's true that cleaning your painting tools can be a water-intensive process. As with cars and dishes, though, there's a big difference between an efficient washing regime and a wasteful one. Choose the former, and there's no reason to violate one of the most basic tenets of green living: Thou shalt choose durable over disposable.

First off, make sure you're using a water-based paint as opposed to a solvent-based one. Water-based paints—which account for the vast majority of the American market—have much lower levels of air-polluting volatile organic compounds; plus, they don't require strong chemicals for cleanup. To find certified low-VOC paints, look to the third-party organizations Green Seal, EcoLogo, or Green Guard.

To clean water-based paint off a dirty brush, all you'll need is soap and some running water. A lot of running water: Most people wash their brushes with something like a five-minute rinse under the faucet—or about 11 gallons from the local reservoir. That's enough water per brush to do three loads of dishes in an ultra-efficient machine.

With a little extra work, you can cut down on the waste. Start by scraping as much paint as possible off each brush, then blot it on old newspaper. Take two coffee cans and fill both with an inch of water. Swish the brush around in can No. 1, and once you've dislodged as much paint as you can, rinse the brush in can No. 2. Pour the dirty water from can No. 2 into can No. 1, refill with another inch of fresh water, and rinse again. The dirty water in can No. 1 can then be used as a pre-rinse for subsequent brushes. A representative for brush manufacturer Purdy estimates that with this method, it takes just a quart of water to clean each brush. (The two-container method works for cleaning roller covers as well, though it'll definitely take more than a quart. A 2002 Danish study found that 3.4 gallons cleaned both the tray and a 7-inch roller washed in the tray—though that was without any manual pre-cleaning.)

If you're careful, cleaning and reusing old brushes actually saves water. After all, it takes a fair bit of water to manufacture a new paintbrush, even if it's the cheap and disposable kind. The bristles are usually made from nylon, polyester, or a blend of the two. According to figures from the industry group PlasticsEurope, it takes between two and seven gallons of water to process and cool the nylon bristles that might be used in a 2.5-inch paintbrush, the most commonly purchased size. Polyester would use a lot less—about two-thirds of a gallon. Either way, that's more than it should take to wash out your brushes at home, and we haven't even considered the water used in other parts of the manufacturing process.

The manufacture of new paintbrushes also means greater usage of plastic or wood for the handle and metal for the ferrule (the part that joins the handle and bristles). Then there's the electricity that powers factories and retail stores and the emissions and fuel usage associated with transportation. Finally, discarded brushes add to the landfill burden.

So for the greenest paint job possible, the Lantern advocates buying a well-made brush, washing it efficiently, and then holding onto it for years to come. Make cleanup easier with a few preventative measures: Wet the brush before you start painting and try not to dip it all the way up to the ferrule, where it's toughest to clean. On multi-day projects, washing out your brush isn't even necessary—put the wet brush in an airtight plastic bag, store it in a cool, dark place, and it'll stay usable overnight.

Before you start worrying about cleanup, though, take a few minutes to consider another kind of renovation-related waste. According to the EPA, 10 percent of paint purchased annually goes unused—that's about 69 million gallons a year. (As Consumer Reports points out, that's enough to cover all five boroughs of New York—three times.) Paint can be recycled, but the process can be costly. Use an online paint calculator to figure out exactly how much paint you'll need, and you can avoid the hassle of dealing with leftover liquid at the end of the day.

Is there an environmental quandary that's been keeping you up at night? Send it to , and check this space every Tuesday.

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Nina Shen Rastogi is a writer and editor in Brooklyn, N.Y.

Illustration by Mark Stamaty.

COMMENTS

Here are a few more things I do that reduce cleanup time and water or solvent use:

Use a brush comb to clean the brush (it looks like a comb with nasty metal spikes for teeth). It really helps remove paint or finish stuck up inside the brush and drastically reduces the amount of washing needed to get the brush clean.

Remove the roller from the handle and wipe off excess paint before washing.

Wash the roller in the paint tray, killing two birds with one stone, er... wash. Fill the tray until the roller is covered and squeegee the roller against the tray. I change the water in the tray about three or four times, which I'd estimate is about three gallons all together.

Stand washed rollers on end to allow residual paint to drain off. If there's still a lot of pigment draining, give it another wash.

When cleaning brushes with mineral spirits, re-cycle the wash solvent by storing it in an emptied jug. Most solids (pigments, etc.) will settle out in a few weeks and you can then use the "cleaned" solvent for most washing. You may be surprised at how clear it is after settling. I only use virgin mineral spirits for thinning and final washes.

These steps have allowed me to keep using a few good-quality brushes and rollers for many years.

-- constantlyamazed
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Before painting, wet the bristles first, all the way to the ferrule, then squeeze out excess water. The brush will be easier to clean after painting.

-- KMMS
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One reason there is excess paint is that people are recommended to make sure that they have enough paint from the same batch to do the entire job, because different batches never quite match. Having a 10% buffer seems reasonable to me.

-- marcparis
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