What to do with leftover paint in Dane County

Sort your paint first

Start with the label. Latex, acrylic and water-based paints clean up with soap and water. Oil-based paints, stains and varnishes say oil-based or alkyd on the can and clean up with paint thinner. The county handles the two differently, and so should you.

Dane County Clean Sweep: what to know before you go

Clean Sweep is the county's household hazardous waste drop-off, at the Dane County Landfill, 7020 Maahic Way, Madison. It is open weekdays and Saturday mornings, with holiday hours posted on the county's page. Households are asked to show proof of Dane County residency, and a per-trip fee applies, which the county lists on its fee schedule.

Businesses must make an appointment, and so should anyone with a large load. The county's examples of a large load include 45 gallons or more of paint, stains or sealants. Clean Sweep may not be able to take an unscheduled large load.

Between them, the county and the EPA give clear packing advice:

• Keep everything in its original container, with the label on.
• If a container is damaged, put it in its own plastic bag.
• Pack boxes or rigid totes so containers stay upright.
• Don't mix products or combine them in bags.
• Expect to unload your own vehicle onto a cart or pallet.

Latex paint: dry it, then trash it

The county's guidance is simple. Latex paint is non-hazardous, and although Clean Sweep will accept it in liquid form, the county recommends solidifying it and putting it in your trash bin. Its page lists dried latex paint among the materials it doesn't take, with the instruction to place it in your regular garbage.

The EPA warns against the shortcuts. Pouring household waste down a drain, onto the ground or into a storm sewer can pollute the environment and threaten human health. Waukesha County's guidance describes how to dry latex paint:

1. Open the can in a ventilated spot away from children and pets.
2. Stir in paint hardener from a hardware store, or mix in cat litter, following the product's directions.
3. Leave it until the paint is completely hard.
4. Put the can in your regular garbage once the paint has fully solidified.

If you have many cans, ask Clean Sweep or your trash hauler what they prefer before you start.

Oil-based paint, stains and thinners

These belong at Clean Sweep. The EPA counts paints among household hazardous waste, because products like paints, cleaners, oils, batteries and pesticides can contain hazardous ingredients. It lists improper disposal as pouring them down the drain, onto the ground, into storm sewers, and in some cases putting them out with regular trash.

Clean Sweep's accepted list includes paint and paint-related materials, architectural coatings, wood finishes, sealers, solvents, and deck stains and cleaners. That covers most of what comes out of a painting or deck staining job.

Storing paint until you can drop it off

Not everyone can get to the landfill the day the job ends. Until you can, the EPA's advice is to keep products in their original containers and never to remove the labels or pour them into food containers. It also notes that household hazardous waste left around the house can be a hazard to children and pets, so store cans where they can't be reached.

Keep latex and oil-based paint in separate boxes, with lids pressed shut, upright and out of the way of foot traffic. That also makes the trip easier, since the county asks you to bring containers upright and unmixed.

Empty cans and the rest of the cleanup

Dane County's list says Clean Sweep doesn't accept empty containers, so ask your trash hauler or municipality what to do with them. Waukesha County's guidance is that empty paint containers can go in the trash only when the paint inside is completely hard, and that empty metal paint cans shouldn't go in the recycling bin.

The EPA adds that even empty containers of household hazardous waste can pose hazards because of residual chemicals, so handle them with care. If you're unsure about anything that touched oil-based paint or thinner, such as rags or a roller cover, ask the county before it goes in the trash.

If the paint is still good

Clean Sweep runs a free Product Exchange. You can bring in usable paint, thinners, solvents and pesticides, and you can take home what other people left. The county limits each customer to one visit a week and to what you can physically carry out. Items are for personal use, can't be resold, and can't be opened or tested in the exchange room. Everything is provided as is, with no promise about its condition.

Before you give paint away, consider keeping a small labeled can for touch-ups. Our posts on storing leftover paint and touching up paint show how to do that so the color matches later.

Buy less so you have less to dispose of

The EPA's advice for products you use only occasionally, like paint, is to buy only as much as you'll use right away. The Dane County Clean Sweep brochure suggests online paint calculators for the same reason. Waukesha County puts average paint coverage at 400 to 450 square feet per gallon, though your walls, color change and primer will shift that.

Our guide on how much paint you need walks through the math. A smaller order means fewer cans to dry out, pack up or drive across town.

If you hire a painter

Ask whoever does the work what they'll do with leftover paint and how they handle cleanup. Our process includes cleanup, and we walk the finished job with you before we call it done. Everything we do indoors is on our interior painting page, and we work across Madison and the towns around it.

If you're repainting an older home and scraping turns up paint chips, remember that Clean Sweep's accepted list doesn't include lead paint chips. Homes built before 1978 are more likely to have lead-based paint, so mention your home's age when you call, and see our post on painting older Madison homes. When you're ready, ask for a free estimate.