Roof Moss Removal in Saanich

Every roof in Saanich has a north side, and the north side is where this starts. Moss does not arrive because a roof is neglected. It arrives because a slope sits in shade, stays damp between October and March, and gives a spore somewhere to hold on. Under a mature Douglas fir or a Garry oak, that describes half the roofs on the street.

Left alone, moss stops being a cosmetic problem. A mat of it holds water against the covering long after the rest of the roof has dried out, and it spreads sideways — into the keyways of a cedar shake, under the butt edge of an asphalt course, along the pan of a concrete tile. As it thickens it lifts what it grows under. Water that gets under a course has somewhere to go that the roof was never designed to send it.

Taking it off is straightforward work done carefully. What decides the method is not the amount of growth. It is what the roof is made of.

Asphalt shingle: the granules are the roof

An asphalt shingle is a mat with a layer of mineral granules fused to the surface. Those granules are the wearing surface and the UV protection both. Lose them and the mat underneath starts ageing at a rate you can measure in years rather than decades.

That single fact rules out most of the quick methods. Pressure lifts granules. So does dragging a stiff blade across a course, and so does working uphill, which pushes both water and debris under the overlap. We work down the slope, lift the growth off rather than scraping through it, and accept that the last stain of it stays until the next few rainfalls take it.

Where growth has been sitting a long time you can usually see the outline of it after it comes off — a patch where the granules are visibly thinner than the shingle around it. That is worth knowing about. It tells you where this roof will fail first, and it is one of the things we point out rather than tidy past.

Cedar shake: soft where it matters

Cedar is the covering that most rewards patience and punishes speed. Growth sits in the keyways between shakes, where it stays wet longest, and a shake that has been damp for fifteen winters is softer than the same shake looked when it went on.

Hand work, then, and a lot of it. The aim is to clear the keyways and the butt line without lifting the shakes or breaking the weathered surface that is doing the shedding. A cedar roof cleared properly still looks like an old cedar roof afterwards — grey, textured, uneven. If it comes back looking new, something was taken off that should have stayed.

Concrete tile: heavy, and easy to walk badly

Tile takes growth along the pan and in the laps, and it can carry a surprising amount before anyone notices from the ground. The risk here is not the cleaning method, it is the walking. Concrete tile cracks under a foot in the wrong place, and a cracked tile does not announce itself — it leaks quietly into the underlay for a year.

So the work is planned around where the load goes, and the growth comes out of the laps rather than off the face alone. Growth in a lap is the part that holds water.

The parts nobody sees from the driveway

Valleys, hips and the lowest two or three courses are where this job is actually won or lost. A valley funnels water from two slopes into one channel; packed growth in a valley turns it into a dam. The lower courses sit above the gutter, stay wet longest, and are the last place anyone looks from the ground.

Those are the places we clear first, because they are the places where the consequences are structural rather than cosmetic. A roof cleaned beautifully on the faces and left packed in the valleys has had the wrong half of it done.

What you will hear afterwards

Standing on a roof shows you things a ladder at the eave never will. You get a plain account of it: which slopes had the worst of it, whether the growth had started to lift any courses, how the granules or the shakes or the tiles are wearing, and whether anything up there wants a roofer rather than us. If the answer is that the roof is fine and will want doing again in three years, that is what you will hear.

We work Monday to Friday, we are insured and WCB-registered, and the estimate is free with nothing attached to it.

Roofs are sorted by covering, not by postcode — start with cedar shake, asphalt shingle or concrete tile, or read what a full roof demossing covers.