Roof cleaning in St. Petersburg
Black streaks gone at garden-hose pressure. We never pressure wash a shingle roof.
Sound familiar?
Is this your house?
Black streaks down the roof
That’s algae, and it feeds on the limestone in the shingles. It comes off with chemistry.
A quote to “pressure wash” it
Pressure strips the granules that shade the shingle from the sun. Most shingle makers say low-pressure cleaning only.
Green on the north side
Moss and lichen where the roof stays damp. Same method, a longer dwell, and a follow-up rinse.
Solution on, working Not treated yet What a soft wash looks like
It looks like nothing is happening. That’s the point.
The solution goes on at about garden-hose pressure and sits. The algae dies where it grows, and the rinse carries it off. No granules go in the gutter.
- Under 100 psi from start to finish.
- Beds wet down first, and rinsed again at the end.
- The streaks keep fading for a week or two after, as the dead algae washes off in the rain.
How we do it
A roof soft wash, in order
Beds and turf wet down
Everything below the drip line soaked first, so the run-off lands on wet leaves.
Solution on, low pressure
Applied from the ground or the roof at about garden-hose pressure.
Time to work
It dwells until the algae is dead. That’s the part that looks like nothing.
Rinsed, and the card
Roof, gutters and beds rinsed, and the method written on your wash card.
What it costs
What decides the price of a roof cleaning
Every job is priced on a written estimate after somebody has looked at the surfaces. These are the things that move the number.
The size and pitch
Square footage, and whether the roof can be reached from a ladder or needs walking.
How bad the growth is
Light streaks take one application. Thick moss and lichen take a second visit.
What’s underneath
Pool cages, lanais and delicate beds below the roof edge take more protection.
The details
For the people who want every step
Why pressure on shingles is the expensive mistake
The granules on an asphalt shingle are the layer doing the work — they carry the UV protection and the fire rating. A pressure washer strips them, and once they are in the gutter they are not coming back. Most shingle manufacturers specify low-pressure chemical cleaning, and a pressure-washed roof can lose its warranty as well as its life.
What a soft wash actually is
A cleaning solution applied at roughly garden-hose pressure, given time to work, then rinsed. The streaking is gone when the chemistry has killed the algae, not when it has been blasted off. It is slower to watch and far better for the roof.
What we do about the plants
Beds and turf below the run-off get wet down before, kept wet during and rinsed after. Anybody who tells you no protection is needed is telling you what is in the mix.
At a glance
Pressure~100 psiMethodChemical, then rinseAt any priceNever pressureQuestions
What people ask us about this
Is soft washing safe for my shingles?
Yes. It’s the method shingle makers recommend. Low pressure and the right solution kill the algae without taking granules off.
How long does a clean roof stay clean?
Usually two to four years here, depending on shade and how close the trees are. North faces come back first.
Do you clean tile and metal roofs too?
Yes, with the same soft wash. Tile can crack under a person’s weight, so we work from ladders and the eaves wherever we can.
Get a straight answer about your house.
Tell us which surfaces and what they look like. We’ll tell you the method and the pressure before anyone quotes you a price.
Other work