Click to enlarge any image small gray or darker round spots on siding that are about 1 16 in individual diameter particularly if the spots are slightly raised may be artillery fungus a mold spore.
Green algae on siding.
Green growth on your siding happens because your siding is not clean.
You re most likely to see green stains on siding that is inadequately ventilated.
These stains occur naturally over time.
Use a brush to scrub the algae from the surface of the vinyl siding.
I simply dissolved the powder in warm water poured it into a simple garden hand pump.
When house siding begins to turn green it diminishes the exterior appearance of the home.
Green stainsare almost always the result of algae or moss.
Algae feeds especially well on sugar.
Algae may also look black or brown as may some molds.
Fortunately siding can be cleaned to remove not only green stains but other dirt and stains that may be taking over the homes exterior.
If you have a lot of trees on your lot or if you have an abundance of woody plants these plants will leave a slight film of sugar deposits on your siding over time especially during spring when pollen and sap are running.
As with any type of exterior finish vinyl siding can become dirty over time due to an accumulation of dirt and grime most of which can be removed with a simple spray of the hose but if you notice the appearance of green stains during your inspection you ll need to take a different approach.
Yellow stainsmean you probably have damaged insulation or deteriorating sheathing behind the siding.
Step 5 rinse the cleaned sections of siding with a garden hose as you go to prevent the soap from drying on the vinyl.
The photo at above left shows green algae on vinyl siding.
Take care to get as little soap as possible beneath the siding.
You may have noticed a green growth on your vinyl siding or gotten an hoa violation letter notifying you that your siding needs to have the green growth cleaned off.
Algae on vinyl siding occurs because organic materials such as dust dirt pollen bird droppings and spider webs accumulate on the siding and algae uses it as a food source.