Power Washing North York

Need Power Washing in North York?

North York exteriors take a beating in a set order every year. Winter salt and grit go up the walls off the road and off your own driveway. Spring rain drives it into the stucco and the siding. Then a humid Toronto summer puts a green-black film of algae on every north wall, shaded fence board and deck board under a tree.

A wash fixes most of that in a day, and it is the step that decides whether a paint job holds. Paint does not stick to a dirty wall, and it sticks even worse to a mildewed one. Call us and we will tell you which surfaces on your place can take real pressure and which should barely be touched.

What Power Washing Actually Takes

The mistake is thinking more pressure means a better clean. On most of a house it means a repair bill. Different surfaces want completely different treatment.

Masonry is the one people wreck. The most careful published standard on cleaning it comes from the U.S. National Park Service, whose guidance for historic masonry says water methods are generally the gentlest means possible, and that you begin at a very low pressure, 100 psi or below, even a garden hose, and work up only as needed, generally no higher than 300 to 400 psi. It also says outright that using water at too high a pressure, which it calls power washing and water blasting, is very abrasive and can easily etch marble and other soft stones as well as some types of brick. There is even a tell for it. If you see grains of stone or sand in the runoff on the ground, the pressure is too high. On a 1950s North York brick bungalow with soft old mortar joints, that is not a theoretical risk.

Before any water goes on masonry, the joints have to be sound and the wall has to be watertight. The same guidance is blunt about why. Otherwise water can seep through the walls to the interior, resulting in rusting metal anchors and stained and ruined plaster. So we look at the mortar first. If it is crumbling, washing it under pressure is the wrong job and we will say so.

Vinyl and aluminum siding are a different problem. The industry body for vinyl siding says to hold the power washer straight at eye level and never aim the stream upward, because water driven up under the laps gets in behind the panels and stays there. It also notes that some siding manufacturers do not recommend power washing at all and others cap the pressure, and it cautions against pressure washing around windows, doors, electrical wiring and plumbing. For a lot of houses, its own advice is that a simple rinse with a garden hose is often enough. For real mildew on a bigger area it points at a mix of 30 percent vinegar to 70 percent water rather than more pressure.

Timing matters too, and this is a real constraint in this city. Water cleaning on masonry should never be done in cold weather or when there is any likelihood of frost or freezing, because water sitting inside the masonry can freeze and cause spalling and cracking. A masonry wall can take over a week to dry out. That is why we do not book brick washing late in the season, and why a wash-then-paint job needs planning rather than a free Saturday in November.

There is also a legal side nobody mentions. Under Toronto's Sewers By-law, only rain and melted snow may enter a storm drain, and the City points out that power washing with water alone still dislodges or dissolves contaminants off the surface being cleaned. Here is the part that should matter to you: the City states that both the person hiring and the mobile wash company are responsible for the wastewater discharging from the property. So we contain or re-route the water away from the catch basin, let it soak or evaporate where that works, and handle it properly where it does not. If a company is blasting your driveway straight into the storm drain, that is your name on it as much as theirs.

Most of our washing happens as prep for painting. For everything else we do outside and in, start at our North York painters page, or see how the exterior work goes in Willowdale and over in Mount Dennis.

The Power Washing We Do in North York

• House siding, stucco and trim

  Vinyl, aluminum and stucco walls, soffit, fascia and trim. We work at eye level and never aim up under the laps, because water forced in behind siding has nowhere to go and comes back as a stain or a smell. Stucco gets a lower pressure and a longer dwell with the cleaner doing the work.

• Decks, porches and fences

  Wood is soft and it fuzzes and splinters if you hit it too hard, so decks and fences get the light end of the range and a wide fan, following the grain. This is also the required first step before any stain, because stain on a dirty or mildewed board fails within a season.

• Brick and masonry, at low pressure

  Brick, block and stone get the gentlest approach we have. Start very low, work up only if needed, and stay well inside the range the conservation guidance publishes. We check the mortar joints first, because washing a wall with failing joints pushes water inside to rust anchors and ruin plaster. If your brick is not up to it, we tell you before we start rather than after.

• Railings, steps, walkways and driveways

  Concrete steps, walks and driveways handle real pressure and usually need it. Metal railings get washed as the first step before any repainting, since salt film and chalked old paint both stop a new coat from grabbing. We keep the runoff controlled here, because this is where most of the dirt and salt ends up.

• The prep wash before painting

  Most of the washing we do is the first day of a paint job. Chalk, dirt, salt film, algae and mildew all have to come off or the paint bonds to them instead of to the house. We also give the surface real time to dry before anything is coated, which is not the same day on masonry.

• Wash water handled to the by-law

  Toronto's Sewers By-law allows only rain and melted snow into a storm drain, and it makes the homeowner as responsible as the washing company for what leaves the property. We contain or divert the water away from the catch basin, let it soak or evaporate where the ground allows, and use an indoor drain where it does not.

Nine Things Worth Knowing Before You Power Wash

1. Start low and work up. The published guidance for masonry is to begin at 100 psi or below, even a garden hose, and go no higher than 300 to 400 psi. You can always add pressure. You cannot put brick back.
2. Watch the runoff. Grains of stone or sand in the water on the ground mean the pressure is too high and you are taking the surface off, not the dirt.
3. Never aim up at siding. Hold the wand at eye level. Water driven upward gets under the laps and behind the panels, and it does not come back out.
4. Check your siding manufacturer first. Some do not recommend power washing at all and others cap the pressure. That instruction beats any general advice, including ours.
5. Stay away from windows, doors, wiring and plumbing. The vinyl siding industry cautions against pressure washing around all four, and those are exactly the places water gets inside.
6. Do not wash masonry in the cold. Water inside brick or stone that then freezes causes spalling and cracking. A masonry wall can take over a week to dry, so late-season brick washing is a bad idea.
7. Let it dry before you paint. A prep wash is not the same day as the first coat on masonry.
8. Cleaner does the work on mildew, not pressure. For a larger mildewed area the vinyl siding industry points at 30 percent vinegar to 70 percent water rather than turning the machine up.
9. Keep the water out of the catch basin. Only rain and melted snow are allowed into a storm drain in Toronto, and the homeowner shares the responsibility for what leaves the property.