Roof Cleaning Chemicals and Cold Weather

Success with Cold Weather Roof Cleaning Projects

With the return of cold weather in most parts of the country, many homeowners investigating DIY asphalt roof cleaning projects ask about the minimum temperature ranges for using roof cleaning products. Minimum temperature guidelines shingle roof cleaning are pretty simple. The roof shingles need be above freezing (at least 35 degrees) for at least four hours before using roof cleaning chemicals for best results. Read on to find out why.

Why temperature affects roof shingle cleaning

Whether it is chilly, or just down right cold outside the factors that impact success in a cold weather DIY roof cleaning project include the air temperature, roof shingle temperature and which roof cleaning product you have selected.

Ambient Air Temperature

In the cold months the air temperature becomes a challenge because every shingle roof cleaning project includes ladders and water. It’s hard enough to spend half a day on your roof getting wet when it is in the 80’s, but drop the temperature to under 45 degrees and you CERTAINLY don’t want to be wet. When it comes to your success in shingle roof cleaning, the air temperature is all about your comfort. You can clean your roof in temperatures as low as 35 degrees, the water won’t freeze, and if you can stand that bitter cold water splashing on you, then you CAN clean your roof.

Asphalt Roof Temperature

During the cold season it is very typical for frost to form when the night time temperatures dip below freezing. Frost is actually ice crystals, and if you were to attempt to clean the roof before these ice crystals melt, your roof cleaning product would need to first melt through the ice, and then do its cleaning job. The net effect of this is that half or more of your roof cleaner’s “energy” is wasted on the ice, rather than on the roof mold.

The solution is to just wait for the roof temperature to warm up. Asphalt roof shingles are heat sinks, so on those cold mornings, when the sun comes out the roof will quickly warm up, retain heat and melt through the frost. So if the forecast is sunny, and the air temperature is forecast to be above 35 degrees, just plan on cleaning the roof after 11am, once the roof has had 4 hours of sun, and above freezing temperatures. The roof mold won’t be wrapped in ice, and it will be a bit more comfortable to clean your roof.

Roof Cleaning Products and Temperature

As always check the instructions on your roof cleaner packaging to determine if any specific temperature guidance is provided. If no specific roof temperature information exists then just follow our guidance above.

35 degrees and a Sunny Disposition

Roof Cleaning in cold weather can be done. Just remember:

  • Sunny Day
  • Temperature Over 35 degrees for 4 hours
  • Water Proof Clothing and Shoes

It’s a tough job to clean your roof in cold weather, but it can be done!


  1. Barbara Reaves September 21, 2012
  2. Cleaner Today Guide March 31, 2013