When to Pressure Wash Your House (and When to Wait)

Run a hand down your siding. If it comes away with a fine, dusty film, that is chalking — the surface of the old coating breaking down. Dark streaks under gutters, green shading on the north side, black spotting on a deck: all of it is growth and grime, and all of it makes a sound house read as a tired one. None of it needs replacing. It needs washing.

The right time is when the surface is dirty and the weather gives it a chance to dry. Late spring is the usual answer around here, once the last of the winter grit and road salt has come off and before summer humidity feeds another round of algae. Any dry stretch through the warm months works.

Pressure is the part people get wrong. Turned up high, a washer will drive water behind siding, scar softwood, blow out failing caulk and strip the top layer off a deck board. The setting has to match what is being washed, and plants, light fixtures, outlets and anything that should not take a direct spray get covered before the machine comes off the truck.

If a repaint is anywhere in your plans, wash first. A clean surface is the only surface paint will properly bond to, so the wash is not an extra job before the painting — it is the first step of it. It also shows you what the house actually looks like underneath, which is a much better basis for choosing a colour than a dirty wall.

Aztecas Quality Painting takes 15% off exterior house washing when it is booked as its own job. Call (412) 512-2438 to arrange a visit.