
How to Pressure Wash your Roof
After following the steps for preparation of the job, proceed in two phases. Water pressure under 2000 psi should be sufficient for a quick and efficient job.
*Begin from a corner of the roof and work your way down, from top to bottom.
* Keep the spray at a 45-degree angle with the surface to avoid gouging and move the nozzle in even strokes at a distance of 8 to 10 inches from the roofing material.
* First power wash the entire surface with an environmentally safe soap to remove mold and fungus.
* Don't let the cleaning solution sit for more than 10 to 15 minutes, particularly if the roof is hot when you are power washing it.
* Next wash everything again with water to remove the grime and residue.
* Finally rinse with plenty of fresh water. If you encounter stubborn stains, attack them with more soap and more water, and if necessary move the power washer over the stain several times.