Will roof washing damage my home or plants?
We answer the most common concern or question we get.
1/20/20262 min read
"Will the chemicals used damage my plants"? "The last guy who washed my house killed all my grass".
These are both very common and wise questions we get from homeowners. The most common chemical used in softwashing is Sodium Hypochlorite (SH). This is also sometimes referred to as bleach or liquid chlorine. The chemical is most commonly used to kill and remove organic growth such as algae, mold, and mildew. We use this to wash our clothes, keep our pools clean, and even clean our bathrooms!
This is also the main reason we use it for roof cleaning and house cleaning. The staining is caused not my age but by organic growth that flourishes in the humid environment of our area, especially in shade.
Short answer, yes chlorine/bleach can kill or damage plants. However, only if it is directly applied and no precautions are taken. A soft-wash has almost no risk of damage to your roof, but it may stain or kill some leaves on a plant from overspray, yet a pressure wash has no risk of damage to the plants but a lot of risk of damage to the roof. No home service has zero risk but here is what you should look for and expect from a professional company cleaning your roof to avoid killing plants:
Pre-wet and post-rinse all plants near spray. Depending on their application method, this becomes more important. Plants tend to absorb the most potent and primary source of liquid. If they are wet before, they will not only absorb diluted bleach but less of it.
Use a neutralizer if neccesary. In many circumstances, pre-wetting with a bleach neutralizer can be a great way to protect the home.
Cover or move susceptible items. If possible move things, or cover before washing. Though some plants are very sensitive to heat and it would be better to just rinse them then to cover them for 2 hours while a wash is complete.
Bag the runoff. Most homes with gutters allow for runoff management, and if we left a gutter into a flowerbed wide open, it could kill many of those plants.
Unfortuantely there are not many alternatives that can be used that work well but do not cause damage. Especially if the staining is bad. The more the cleaner sprays away from plants, pre-wets and rinses plants, and manages runoff then you should have no problems! This is one of the main reasons hiring a professional and experienced roof cleaner is worth a little extra money!