Why we use chemicals instead of only water pressure
There's two main reasons why we use chemicals to clean instead of only water pressure.
#1 When you rely on only pressure to clean surfaces, you need a lot of pressure. Usually a minimum of 2,000 PSI, and upwards of 4,000 PSI to blast off organic material. This amount of water pressure is enough to cut through wood easily. If you're only using water pressure to clean a home it's nearly impossible to do the job right and not cause any damage to the home, which is an unacceptable business model.
#2 By only using water pressure, you're not fully cleaning a surface. All materials, whether it's vinyl siding, shingles, wood, concrete, or brick, have pits and grooves on their surface. The geometry of these pits and grooves prevents water pressure from directly blasting away all organic material (moss, mold, lichen, algae), leaving behind spores from which new material can grow from. An analogy would be only cutting the leaves of a weed - the root system is still in place and it can quickly grow back.
This is where chemicals come in. By choosing to clean with the right chemicals and mixing the potency properly, this completely changes how you clean surfaces. Instead of blasting away organic material with only water pressure, we're instead applying a solution with low pressure that kills organic material. Then, we rinse off the dead material using low pressure (60 PSI). This is how we can quickly and effectively clean your home while still ensuring we're using low enough pressure as to not cause any damage. No organic material is left and your home exterior is completely clean. In relation to the analogy with weeds, cleaning with chemicals is effectively pulling out the weed, roots and all. Your home will stay clean longer with our process.
This system is why Pen Bay Power Wash is a better option than a homeowner doing it themselves or hiring a general contractor to do it. This is our expertise! Our process is safer and longer lasting than conventional pressure washing.