Why should you clean your roof? The obvious reason is to improve the appearance and thus the property value of your home, but it can also increase energy efficiency as well as the roof’s lifespan. If you keep your roof well-maintained, it should last upwards of 30 years. So how can you keep a roof clean?
Typical methods involve pressure cleanings or chemical solutions with chlorine bleach or sodium hydroxide. When use properly these methods will clean your roof with minimal detrimental impact; however, the effects can be very temporary and will have to be repeated ever six to 18 months to maintain the appearance.
Every method has positive and negative effects:
- Chlorine: faster cleaning process with minimal rinsing, but can be toxic to people and plants.
- Sodium hydroxide: safer for landscaping and effective in getting rid of grease, but is toxic and caustic and can cause irreversible damage if used in high levels.
- Pressure cleaning: doesn’t require chemicals and has a lower cost, but it should only be used on concrete, barrel tile or metal roofs since it applies a lot of pressure to the roof surface.
All the above methods are relatively safe and effective, but can lead to premature roof aging if used repeatedly since they add to the natural erosion that comes from strong weather.
A preventative maintenance program should eliminate the need for cleaning and the damage that may come along with it. A light spray of chlorine and water or an algae prevention product can prevent the recurrence of algae growth on your roof.
Courtesy of Roofer 911
http://www.roofer911.com/asphalt-shingle-cleaning-101.htm
