When (and Why) to Wash Your Roof & House in Wellington

Walk down any Wellington street and you'll spot it: green and black streaks creeping across roofs, and that grey film building up on weatherboards. It's not just cosmetic — left long enough, moss and lichen can shorten the life of your roof and cladding.

Why houses get dirty faster here

Our cool, damp climate and sheltered, shady spots are perfect for moss and lichen. South-facing walls, homes under trees, and anywhere that doesn't get much sun grow it fastest — and the salt air near the coast doesn't help.

How often should you wash?

As a rule of thumb, a house wash every one to two years keeps most homes fresh and stops build-up becoming permanent. Roofs can go a little longer, but heavy moss is worth treating sooner, before it lifts tiles.

Soft wash, not blast

Your roof and cladding should be soft-washed, not blasted at high pressure. High pressure can force water under tiles and strip coatings. A low-pressure soft wash with the right treatment kills the moss at the root and lasts longer.

The best time of year

Late spring through summer is ideal — surfaces dry faster and you head into the wet season clean and protected. That said, a wash any time beats letting build-up sit.