Confused by roof cleaning services?


Homeowners often find confusing information when researching roof cleaning services. To assist homeowners with making informed decisions when deciding on which roof-cleaning contractor to hire, this information describes the differences between the three main roof-cleaning methods.

Eco-friendly, non-bleach, low-pressure roof cleaning

Roof cleaning companies that use this method use high-grade eco-friendly products that do not contain toxic chemicals such as chlorine-bleach, phosphates or other chemicals that can kill vegetation and pollute waterways. This method also uses a low-pressure rinsing system, avoiding the use of damaging high pressure scrubbing or brushing.

Pros: Typically, the results with this method are instant and complete. Technicians use eco-friendly roof cleaning products such as roof shampoo and equipment designed precisely for safe, gentle roof cleaning. Contractors who use this method clean the roof while preserving the integrity of the shingles and without damaging the landscaping.

Cons: This method may be more costly due to the cost of the eco-friendly products vs. inexpensive chlorine bleach mixtures.

Chlorine-bleach roof cleaning

Roof cleaning contractors who use sodium hypochlorite (chlorine bleach) mix it with high concentrations of other chemicals such as trisodium phosphate, also known as TSP.  They spray it on the roof and wait for it to dry and then re-apply it several times as needed. Stains that don’t come off on the day of treatment may eventually come off with rain in the months to come.

Pros: The bleach method can be less expensive than other methods because the chemicals are inexpensive and the technicians generally don’t get on the roof to rinse or inspect after the application.

Cons: There can be a strong chemical odor and results that may not be instant, particularly when moss and lichen colonies are involved. There is also a possibility of causing harm to people and pets if exposed to the fumes or fluids. The effects of bleach on landscaping can cause permanent damage to plants, trees, grass and shrubs.

High-pressure power washing

Some roof-cleaning contractors use high-pressure power washing methods to attempt to remove roof stains.

Pros: Can’t think of many. But the alternative to not cleaning is a roof with a life-expectancy of 25-years only lasting 15 years if nothing is done. We advise consulting a professional that knows that different roof tiles require different types of water jets and cleaning solutions to get the roof clean.

Cons: Not only can this method be damaging to shingles, but it’s also not an effective way to remove organisms that cause roof stains. The high-pressure power washing method leaves root systems behind, so the algae will often return rather quickly.

Tip: If you’re not sure if the contractor will be using damaging high pressure, ask him to hold his hand under the spray. If he can’t do that, then the pressure is too high and can damage your shingles.

Knowing the pros and cons of the three main types of roof cleaning services means you will be well prepared to ask the right questions to the professional cleaning your roof. Not only will removing ugly roof stains greatly improve a home’s curb appeal, but also the roof will be restored to its natural and healthy energy efficient state. Remember, a clean roof is a healthy roof that should last for years to come. If you have questions, contact us. We look forward to hearing from you.

Premo Roofing