Metal & Corrugated Roof Cleaning

IMPORTANT NOTES:

Many metal roofs do not have decking underneath. Determine the structural integrity of the roof before you decide to walk on it. 

Metal roofs become EXTREMELY slippery when wet. It is not recommended to work on them at all. Alternatively, you can work from a ladder or from a boom arm over the roof.

Metal roofs have vents at the top ridges that allow hot air to escape. DO NOT SHOOT WATER OR CHEMICAL INTO THIS SPACE as it will lead directly into the structure. Always clean from the top down.

PROPORTIONED METHOD EQUIPMENT:

• Soft Wash System 5 GPM or Better, 60 PSI or Better

• Soft Wash Proportioner

• Soft Wash Wand and J-Rod Nozzle

X-JET METHOD EQUIPMENT:

• Pressure Washer: 4 GPM or better, 2000 PSI or better

• Pressure Washing Wand with X-Jet Nozzle

AVERAGE CLEANING RATE:

500-1000 sq ft per hour

SCOPE OF WORK:

Before beginning, ensure you have completed all the steps in the Worksite Preparation Guide.

1. CLEAR DEBRIS

   Use a leaf blower or partially open ball valve to clean tree branches, pine needles and any other loose debris from the roof. Be mindful of where the debris falls.

2. PRE-SOAK NEARBY VEGETATION

   It is important to wet nearby plants, grass, bushes, trees, and other vegetation the soft wash solution has the potential of interacting with. Keep these areas wet as you are applying the chemical. Doing so will create a hydro barrier and minimize the chances of damage. 

3. APPLY SOFT WASH SOLUTION

   Adjust your proportioned settings or X-Jet Nozzles to reach 3% sodium hypochlorite dilution level. (See: Soft Wash Mixing Ratios) For roofs with a low pitch use a low amount of soap. Increase the amount of soap depending on the steepness of the roof. Applying mixture will begin to break down organics and clean the surface. Apply a even coating across the entire surface.

   Pro Tip: While one technician is on the ladder or roof applying chemical, have another technician wetting the landscape, trees, bushes and house underneath. This will prevent the soft wash solution from killing unintended organics or damaging the property.
   
   Pro Tip: Do not spray into any vents or opening on the roof. Also, be mindful of over spray or chemical entering the gutters. You want as much treatment to stay on the roof as possible. 
   

4. ALLOW TO DWELL

   While keeping the surface wet, allow up to 30 minutes of dwelling time for the soft wash solution to work. The moss will begin to turn white and the black algae will begin to disappear.

   Pro Tip: Do not allow the soft wash solution to dry on a metal roof. This can cause flash oxidation and discoloration. Instead, keep the roof wet by lightly misting for the dwelling period.

5. RINSE & INSPECT (OPTIONAL)

   Once the entire surface has been treated, you have the option to rinse. You can advise the customer that it would be best to leave the chemical as long as possible and let the rainwater rinse of the roof. In some cases, customer may need to get the best curbside appeal as fast as possible. This can include mandates from HOA or putting a home up for sale. In these cases, you can begin rising the roof with clean water after 30-60 minutes of dwell time.