Repair damaged plaster before painting ceiling

[Joanna]

How important is it to repair plaster before repainting?

Our ceilings have peeling paint that we're pretty sure was caused by past water damage.

Since the water problem is no longer an issue, can we simply repaint the ceilings or should we first repair any underlying plaster damage?

[home improvement guy]

It's always a good idea to repair damaged plaster before painting.

For paint to adhere properly and look good over time, surface condition and preparation are crucial. You should repair a damaged surface properly and then prime and paint it. If water damage affected the plaster's integrity, and you just paint over the damage, the paint will likely fail. It might immediately chip and crack or over time it might bubble. Worse yet, because plaster is strong but brittle, a damaged section could fall and even hurt someone.

However, before turning your attention to plaster repair or painting, be certain you know what caused the water damage. Make sure to fix any leaks or broken pipes and remove soiled insulation.

Plaster repair can, in some cases, be a do-it-yourself project. But unlike drywall, plaster doesn't come in a solid sheet. It isn't as easy to work with as drywall mud because it must be applied in layers and it sets up quickly. Unless you have experience and are confident the plaster area contains no lead paint, it's a job best left to a pro.

Potential plaster-repair pros include plaster specialists as well as many painters, handyman services and carpenters. Homes built with plaster - typically from before the 1950s - may feature lead paint, which was banned in 1978. Because lead paint, even in small amounts, is a serious health hazard, it's important that an EPA-certified service provider do the plaster work if lead is present.

The cost to hire professional plaster repair work will vary, depending on the extent of the damage and where it's located. Most service providers familiar with repairing plaster will charge a straight hourly fee for this type of work, which can range from $30 to $80 or sometimes more, depending on where you live and who you hire.

In the case of water damage causing only a stain, without affecting the plaster's integrity, you should be fine to prime the stained area with a stain blocker, such as Kilz sealer, and then paint. Pros recommend using a high-quality latex paint over plaster. Consider using a satin-finish paint if the ceiling is in a moisture-rich area, such as a bathroom or laundry room.

As always, make sure you consider plaster-repair and paint pros who've earned positive consumer reviews on a trusted site; are appropriately licensed, insured and bonded; and use written contracts.