Getting the lead out

Stripping toxic paint can be a complicated — and costly — endeavour

Q I have an old house with an old door that has been painted over and over and looks horrible. It is on the side of the house that faces east, which does not help, as the door gets baked at sunrise. What is the best way to sand a door like this and repaint it so it might look decent for a while?

A An old door on an old house very likely has lead paint, so your first step isn’t sanding. You need to remove the old paint if you want a smooth finish, and sanding is not the way to start when lead paint is involved.

Stripping paint, even when it doesn’t contain lead, is a messy task. One option is to turn the entire job over to a company that can hand-strip, sand where necessary and apply new finish. Of course, a custom job like this can be quite expensive, so if spending that much money to repaint the door isn’t in your budget, you have other options. One is to take the door to a company to have the door stripped, then either paint it yourself or hire a painter for just that step. One industrial process involves immersing the door in a vat filled with a chemical stripper, which takes off all the paint, and then neutralizes the wood so new finish will stick well.

Keep in mind that once you’ve had all the paint removed, if you wanted to do the repainting yourself, you might still need to do some prep work. Doors exposed to a lot of ultraviolet light from the sun often have a peach-fuzz texture once the paint is off and you would need to sand that to get a smooth surface. If you don’t feel equipped to remove and transport the door and temporarily cover the opening with plywood, you can hire a handyman service for that.

You can also hire a painter to strip and repaint the door at your house, or do the work yourself. Either way, one benefit of this approach is that you could probably eliminate the need to keep the door off its hinges overnight.

Two requirements apply to stripping paint from a door. If you or a painter use a heat gun rather than a chemical stripper to soften the paint so it can be scraped off, the setting needs to be below 1,100 degrees Fahrenheit. Lead vaporizes at that temperature, which allows it to spread through the air and contaminate a wide area. You won’t need anything even remotely that hot, because paint softens at 400 to 600 degrees. And if you do sand to get a smooth surface, mist the area and use wet-dry sandpaper so the dust doesn’t become airborne. If you use a power sander, it needs to be connected to a vacuum with a HEPA filter, which captures superfine dust.

If you do the work yourself, you’re also responsible for disposing of the residue safely. Local requirements vary, so check with your waste disposal company or municipal hazardous waste agency.

Once the paint is off and the surface is smooth, apply a primer topped by at least two coats of exterior paint. Choose a semigloss formula rather than matte, because it results in a smoother finish that doesn’t show fingerprints as easily. The water-based, acrylic paints sold at paint stores and home centres work well, provided you pass over the cheapest formulas, and if you later want a different colour, they’ll be easier to paint over than if you used a specialty paint with a different chemistry.

Read the full label before you paint. Many paints work best if applied when the air and surface temperatures are 50 to 90 degrees Fahrenheit. If you paint the door when it’s off its hinges, you can set up an interior workspace to achieve that in any season. If you paint with the door in place, wait until it is no longer in direct sun, which would cause the paint to skin over too fast and not cure properly.

For The Washington Post