5212 22nd Ave. Seattle, WA  98105

Safe & Effective

     Roof Treating or Cleaning done properly can be a Safe and effective way to extend the life of your roof while helping keeping your house looking in top shape.  We recommend the safest gentlest option to clean-treat your roof based condition of your roof.  

Because of the fragile nature of the small rocks coating this kind of roof we offer a treatment only option with a light scrape.  The scraping is only to pop off moss 1/2 inch or greater in height, the mechanical action needed to remove moss would also removes the roofing granules, that's why we only do a light scrape of larger moss.  For this option w e start with the light scrape, then blow off the roof, clean out the gutters, and lastly apply a Zinc Sulfate treatment to kill moss.  We clean the gutters either by hand or blowing, and prefer blowing when possible as it is a little more thorough and can save you money if debris can be blown into beds and bushes- more likely when debris is dry and or you have facia board behind the gutters.  The Zinc treatment is in the form of a powder that washes down over the moss within the next few rains and completely disappears after it treats the moss.  Then each year as you clean your gutters  another zinc treatment can be applied if needed to keep the growth from coming back, without the need for scraping or blowing the moss.  Some houses need to be treated up to 2 times a year (until moss falls off then less often) and some can go a few years without needing to be retreated.  The Average size roof is around $175-300 for this option but can be more or less based on your specific situation, with  follow ups less and if done with another service very reasonable.

528-6146
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Greenworks
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(206) 528-6146

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17060 11th Ave. NE Shoreline, WA  98155

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Option 2: Pressure Wash Roof, Clean Gutters - done with a safe neutral soap, and bleach.
This option can be done on newer sound roofs that are walkable with minimal wear on the roof , we recommend treating steeper or older roofs.   We use a round surface cleaner (as much as possible) with 2 high speed nozzle spinning in a circle so it never sits in one place long, making for an even, gentler clean.   Moss can have roots as fibery/strong as tree roots.People who advertise low pressure washing are using a strong cleaner/degreasers to soften the roots attached to the granules, which we don't recommend.   Your roof is tar, which is broken down by degreasers/Alkalies, exposing the lime added to harden the tar. which moss thrives on.  Surface cleaners are safer, gentler, and more efficient than cleaning with the pressure wand by hand, but more slightly more agressive on a new roof than treating.  Once cleaned the roof can be regularly maintained by a zinc treatment as growth occurs.  The Average size roof cost around $350-600 (cleaning with a degreaser is much faster and better for the contractor not you)

Option 1: Treatment of Moss on Roof, light scrape (to knock of anything 1/2 or greater), blow off Roof, Clean Gutters

Composite shingles, have a small granular sand, in a tar base.  The tar base is mixed with limestone to thicken the tar, which sadly is a food for moss, mold, mildew, & Algae.  Couple this with wet moist weather of the northwest for a significant portion of the year and you have perfect contions for growth that can damage your composite roof by loosening the granuals that protects the roof & tar.  Dead moss will not hurt your roof, nor of course can it if we are able to pressure wash it all off.

GENTLE ROOF
TREATMENTS
& CLEANING

GENTLE ROOF
TREATMENTS,
& CLEANING

Light scrape, blow, clean gutters, apply Zinc to kill remaining moss