# Roof Cleaning Toronto | Power Pressure Washing

> Roof cleaning in Toronto, ON. Low-pressure soft wash removes moss, algae and black streaks. Written quote per surface. Call (647) 277-5411.

URL: https://powerpressurewashingtoronto.ca/roof-cleaning-toronto/

![Toronto shingle roof under maple canopy, half soft washed to show clean versus black-streaked shingles](/images/misc/asphalt-shingle-roof-of-toronto-home-under-mature-.webp)

# Roof Soft Washing for Moss, Algae and Black Streaks

Last updated: October 16, 2026

Low-pressure soft wash with sodium hypochlorite for moss, algae and black streaks on asphalt shingles, with gutter rinse and plant protection.

-   Low-pressure SoftWash, zero blasting
-   Moss, algae and black streak removal
-   Gutter and plant rinse protocol
-   Photo report

20+ YRS

GTA Combined

$2M COI

Liability + WSIB

24/7

Phone Answered

Typical range **$450-$850** per roof

Request a Free Written Quote

[#quote →](#quote)

 

Call (647) 277-5411

[tel:+16472775411 →](tel:+16472775411)

24/7 phone answered. Weekend bookings standard.

Quote: Roof Cleaning

Fixed per-surface pricing. No hidden trip fees.

Thanks, we got your request.

We confirm a written per-surface quote, usually the same day. Need it faster? Call (647) 277-5411.

-   20+ Yrs Combined GTA Experience
-   $2M Liability + WSIB
-   10 GTA Cities Served
-   24/7 Phone Answered
-   24 Hrs Commercial COI

Roof cleaning in Toronto should never involve a pressure washer. The black streaks and moss on shaded shingles are living organisms, and the right way to remove them is to kill them at the root with a low-pressure soft wash, not to blast them and the shingle granules off together. That is the only way we clean roofs.

## Why Do Toronto Roofs Grow Moss and Black Streaks?

Toronto’s mature tree canopy is beautiful, and it keeps north-facing roof slopes in shade most of the day. Add humid lake summers and you have the perfect home for **Gloeocapsa magma**, the algae behind black streaks, along with green moss and grey lichen. The algae feed on the limestone filler in asphalt shingles and spread from roof to roof on the wind. Moss holds moisture against the shingles and can lift their edges.

Rosedale, Forest Hill, Hoggs Hollow and Unionville see the worst of it, but any roof under big trees is at risk. Left alone, moss and lichen shorten shingle life and can push water under the tabs.

## What Is Roof Soft Washing?

Soft washing uses chemistry instead of force. Our SoftWash low-pressure line applies a measured mix of diluted sodium hypochlorite and a surfactant that helps it cling to the shingles. The mix dwells long enough to kill algae, moss and lichen, and then the roof is gently rinsed where appropriate. Water pressure stays about the same as a garden hose.

![Crew applying a low-pressure soft wash mix to a mossy roof slope with gardens pre-wet below](/images/content/crew-member-on-ground-applying-low-pressure-soft-w.webp)

## Why Pressure Washing a Roof Is a Mistake

Asphalt shingles are covered in ceramic-coated granules that protect the asphalt from UV. A pressure washer strips those granules away, which ages the roof by years in an afternoon. It can also drive water under shingle tabs and into the roof deck. Many shingle manufacturers specifically warn against pressure washing and recommend low-pressure cleaning with diluted sodium hypochlorite instead.

## Types of Roof Growth We Treat

| Growth | What it looks like | Treatment |
| --- | --- | --- |
| Gloeocapsa magma (algae) | Black or dark grey streaks running down the slope | Soft wash, lightens same day |
| Moss | Green, cushiony clumps along edges and shaded areas | Soft wash, releases over next rains |
| Lichen | Flat grey-green crusty patches | Soft wash, may need follow-up |

## When Should You Book Roof Cleaning?

-   Black streaks are visible from the street
-   Moss is building along the lower edges or north slope
-   You are listing the home and want photos to show a clean roof
-   Gutters keep clogging with granules and organic debris
-   You want to extend the life of a roof in good structural shape

We work in calm, dry, mild weather, usually spring through fall. Winter roof problems are ice dams, which our 

ice dam removal

[/ice-dam-removal-toronto/ →](/ice-dam-removal-toronto/)

 service handles with a steam rig.

## How Much Does Roof Cleaning Cost in Toronto?

### Pricing

Typical roof soft washing runs **$450-$850** and takes **2-4 hours**. A bungalow or small roof is usually $450-$550, a two-storey home $550-$750 and large or heavily mossed roofs $750-$850. Large estate roofs and steep pitches are quoted individually. Pair it with a 

house wash

[/house-washing-toronto/ →](/house-washing-toronto/)

 for a better combined rate.

## What to Expect on Roof Cleaning Day

1.  **Arrival and check.** The crew confirms the slopes to treat, checks gutters and looks for loose or damaged shingles from the ground and ladder.
2.  **Garden protection.** Beds and shrubs below the eaves are soaked with clean water. Downspouts are directed away from sensitive plants where possible.
3.  **Application.** The soft wash mix is applied from the eaves upward at low pressure. Crews stay off the roof surface whenever the slope can be reached from a ladder.
4.  **Dwell.** The solution works for several minutes. Black streaks start to lighten almost immediately.
5.  **Gutter and plant rinse.** Gutters and downspouts are flushed and plants are rinsed a second time.
6.  **Photos and explanation.** You get ladder photos and a clear explanation of what will happen with any remaining moss over the next few rains.

## Common Roof Problems We Solve

### Black streaks on the north slope

Gloeocapsa magma loves the slope that gets the least sun. Soft washing clears the streaks the same day in most cases.

### Moss along the eaves

Moss collects where water lingers at the bottom edge. It dies on contact and loosens over the following rains, with no scraping.

### Lichen around vents and chimneys

Lichen is the toughest growth to clear and may need a second application. It slowly releases once dead.

### Granules in the gutters

Some granule loss is normal with age, but heavy loss after pressure washing or scraping is a warning sign. Soft washing adds no granule loss of its own.

## Keeping Moss and Algae Away

Trimming branches to let in light, clearing gutters each fall and booking a soft wash before growth gets thick all extend the time between cleanings. Zinc or copper strips near the ridge can slow regrowth on some roofs, and we can advise whether they suit yours.

## Roof Cleaning Across the GTA

Power Pressure Washing Toronto

[/ →](/)

 soft washes roofs throughout 

Toronto Central

[/service-areas/toronto/ →](/service-areas/toronto/)

, in shaded estates in North York, on wooded Oak Ridges Moraine lots in 

Richmond Hill

[/service-areas/richmond-hill/ →](/service-areas/richmond-hill/)

, in Unionville and Markham Village, and across the rest of the GTA. For siding, stucco and heritage masonry, see our 

soft washing

[/soft-washing-toronto/ →](/soft-washing-toronto/)

 service. Our blog post on 

soft washing a Toronto roof

[/blog/soft-washing-toronto-roof-moss-algae-black-streaks/ →](/blog/soft-washing-toronto-roof-moss-algae-black-streaks/)

 goes deeper on the method.

Transparent pricing

## How Much Does Roof Cleaning Cost in Toronto?

Every job starts with a written quote per surface before any work. No hidden fees, no trip charges added on the day.

Bungalow or small roof $450-$550

Time: 2 hrs

Two-storey home $550-$750

Time: 2-3 hrs

Large or heavily mossed roof $750-$850

Time: 3-4 hrs

Typical roofs take 2-4 hours. Large estate roofs, steep pitches or heavy moss are quoted individually. Add to a house wash or fall package to save.

Request a Free Written Quote

[#quote →](#quote)

 

Full GTA price list

[/pricing/ →](/pricing/)

Why us

## Why Choose Power Pressure Washing Toronto for Roof Cleaning?

### No pressure on your shingles

Pressure strips the granules that protect shingles from UV. Soft washing kills the growth without touching them.

### Kills it at the root

Sodium hypochlorite treats Gloeocapsa magma, algae and moss spores, so results last much longer than scraping.

### Gardens protected

Plants are pre-wet and rinsed again after. Overspray is controlled on calm, dry days.

### Clear pricing

Typical roofs $450-$850, written before any work.

## Ready to book roof cleaning?

Send a photo or call. We tell you hot, cold or soft wash, and put the price in writing first.

(647) 277-5411

[tel:+16472775411 →](tel:+16472775411)

 

Get a Written Quote

[/contact/ →](/contact/)

How it works

## How Does Our Roof Cleaning Service Work?

1.  1
    
    ### Roof check
    
    From the ground or ladder we check shingle type, condition, moss load, gutters and the plants below.
    
2.  2
    
    ### Protect the property
    
    Gardens are pre-wet, downspouts managed and pets kept inside.
    
3.  3
    
    ### Soft wash, no pressure
    
    Diluted sodium hypochlorite and surfactant applied at low pressure, left to dwell, never blasted.
    
4.  4
    
    ### Rinse and photos
    
    Gutters and plants rinsed, ladder photos taken, and we explain how residual moss will release.
    

Our work

## Roof Cleaning Work Across the GTA

Click any photo to enlarge.

 

See the difference

## Before and After

![Roof Cleaning before cleaning](/images/misc/before-toronto-asphalt-shingle-roof-with-dark-gloe.webp) Before

![Roof Cleaning after cleaning](/images/misc/after-toronto-asphalt-shingle-roof-even-clean-colo.webp) After

North roof slope: black streaks and moss treated with zero pressure

Case study

## A Recent Roof Cleaning Project

![Unionville shingle roof under a silver maple during a low-pressure soft wash](/images/features/asphalt-shingle-roof-of-unionville-markham-home-un.webp)

Unionville, Markham

### Unionville Roof Soft Wash

Rig: SoftWash low-pressure line

A Unionville homeowner in Markham had black streaks and moss creeping up the north slope of a fifteen-year-old shingle roof under a large silver maple. We pre-wet the gardens, applied a low-pressure soft wash to kill the algae and moss at the root, rinsed the gutters and downspouts, and explained that the remaining moss would release over the next few rains without any scraping.

Roof Cleaning

[/roof-cleaning-toronto/ →](/roof-cleaning-toronto/)

 

Markham service area

[/service-areas/markham/ →](/service-areas/markham/)

Client results

## What Clients Say About Our Roof Cleaning Work

Real jobs, real prices, written quote first.

Hannah C.

Hoggs Hollow

$685

> "Black streaks and moss on the north side of our roof had been bothering us for years. They did not use any pressure on the shingles, just a low-pressure soft wash, and they wet down all the gardens first. The streaks were gone the same day and the moss let go after a couple of rains, exactly as they said it would. The gutters were rinsed out too, and they left photos of the roof from the ladder so we could see the result up close."

Roof soft wash

Richard T.

Cabbagetown

$380

> "Soft wash on our Cabbagetown limestone was gentle enough that the heritage inspector approved on first look. Previous company left streaking."

Heritage limestone soft wash

Claire D.

The Annex

$520

> "Our 1890s brick semi had green staining and black spots on the shaded side. I was nervous about pressure on old mortar, but they explained the soft wash and did a small test patch first. The brick came up clean and the mortar is untouched. Very respectful of an old house. They even pointed out a spot of failing mortar near the porch so we could have a mason look at it before winter."

Victorian brick soft wash

Daniel R.

The Beaches

$340

> "We live under big trees near the boardwalk and our side walkway was green and slippery most of the year. They soft washed the moss instead of blasting it, then rinsed the patio stone and reset some of the joint sand. My kids stopped slipping. They also gave me a straight answer on how often to book it again, which was refreshing. Weekend booking made it easy."

Patio + shaded walkways

Andrew B.

Forest Hill

$840

> "Our interlock driveway had lost most of its joint sand after a rough winter and weeds were coming through. They cleaned it, swept in new polymeric sand and sealed it with a natural finish, all on the same day. They explained the cure time clearly and roped it off for us. A year later the joints are still tight and the weeds have not come back. The price matched the written quote to the dollar, and they left the street cleaner than they found it. Our neighbours on the next street have since booked them for their own interlock."

Interlock clean + polymeric reseal

Got questions?

## Roof Cleaning FAQs

### Do you pressure wash roofs?

No. Roofs are soft washed at low pressure with sodium hypochlorite and surfactant, which kills moss, algae and black streaks without stripping shingle granules. Typical roofs run $450-$850.

### What are the black streaks on my roof?

Usually Gloeocapsa magma, an algae that feeds on the limestone filler in asphalt shingles. It spreads from roof to roof on the wind and thrives on shaded, damp slopes under Toronto's tree canopy.

### Does roof soft washing void a shingle warranty?

Several major shingle manufacturers recommend low-pressure cleaning with diluted sodium hypochlorite for algae removal, and warn against pressure washing. Check your specific warranty, but soft washing is the method manufacturers generally accept.

### How long until the moss falls off?

Algae and black streaks usually lighten the same day. Thick moss dies on contact but releases over the next few rains rather than being scraped off, which protects the shingles.

### How often should a roof be soft washed?

Most Toronto roofs stay clean for three to five years after a soft wash. Heavily shaded roofs under large trees may need treatment every two to three years.

### Is soft washing safe for my plants and pets?

Yes, with precautions. We pre-wet plants, use a diluted mix, control overspray and rinse plants again afterwards. Pets should stay inside until surfaces are rinsed and dry.

Still have questions?

The phone is answered 24/7. Ask about your surface, schedule or COI.

(647) 277-5411

[tel:+16472775411 →](tel:+16472775411)

Ask in Writing

[/contact/ →](/contact/)

## Related Services

![Cabbagetown Victorian heritage home with limestone trim being gently soft washed](/images/misc/cabbagetown-toronto-victorian-heritage-home-with-l.webp)

### Soft Washing

Chemistry-driven low-pressure cleaning for stucco, vinyl, shingles and heritage masonry such as Annex Victorian brick and Cabbagetown limestone.

[Soft Washing →](/soft-washing-toronto/)

![Two-storey Toronto home with vinyl siding and brick being soft washed](/images/misc/two-storey-toronto-home-with-white-vinyl-siding-an.webp)

### House Washing

Full-house exterior wash: soft wash for vinyl, aluminum and stucco, controlled cold pressure for brick, plants protected throughout.

[House Washing →](/house-washing-toronto/)

![Crew in fall-arrest gear steaming an ice dam along the eaves of a snowy Toronto house](/images/misc/crew-in-fall-arrest-harness-steaming-thick-ice-dam.webp)

### Ice Dam Removal

Winter emergency ice dam removal using a low-pressure steam rig and safe roof access, with a 24/7 phone line through the season.

[Ice Dam Removal →](/ice-dam-removal-toronto/)

Nearest service areas

Pressure washing in Toronto Central

[/service-areas/toronto/ →](/service-areas/toronto/)

 

Pressure washing in Richmond Hill

[/service-areas/richmond-hill/ →](/service-areas/richmond-hill/)

 

All GTA service areas

[/service-areas/ →](/service-areas/)

## Try Our Free Cost Calculator

Pressure Washing Cost Estimator

[/tools/pressure-washing-cost-estimator/ →](/tools/pressure-washing-cost-estimator/)

![](/images/hero/power-washing-crew-in-deep-lake-blue-shirts-beside.webp)

Phone answered 24/7 · Weekend bookings standard

## Ready to Book Roof Cleaning?

Roof Cleaning across Toronto and the GTA with the right rig for every surface and a written quote before any work.

Request a Free Written Quote

[/contact/ →](/contact/)

 

Call (647) 277-5411

[tel:+16472775411 →](tel:+16472775411)

-   Written quote per surface
-   $2M liability + WSIB
-   COI in 24 hours
-   Code 681 wash water recovery