House washing · 3 min read
Should you wash your house before painting?
Why washing your house before painting matters, how long to wait before painting, and what a pre-paint wash should include.
- Yes, paint needs a clean surface to bond properly
- Mould left under new paint can grow through it
- Let surfaces dry fully before painting
Yes. Washing before painting is one of the most important steps in a long-lasting paint job, and most painters will insist on it.
Why it matters
Paint needs a clean, sound surface to bond to. Dust, chalky old paint, traffic film and mould all get in the way. Paint applied over mould can trap it underneath, where it keeps growing and can show through or cause the new paint to fail early.
What a pre-paint wash should include
- Killing mould, mildew and algae, not just rinsing them
- Removing chalky residue from old paint
- Cleaning soffits and eaves, where dirt and cobwebs collect
- A thorough rinse so no cleaning residue is left behind
How long to wait before painting
Surfaces need to be completely dry before painting. In good weather that’s often a day or two, but follow your painter’s or paint manufacturer’s advice, especially in cooler months.
Planning a repaint? Book a soft house wash a few days ahead so your painter starts with a clean surface.
Frequently asked questions
Can I water-blast my house before painting?
High pressure can drive water into timber and behind cladding, which then needs longer to dry. A soft wash cleans without soaking the substrate.
Maidly looks after homes across Christchurch with eco-friendly methods and a 100% work guarantee on every service. Request a free quote.