Back in the late 90's, when we were known as Action Power Wash down in Miami, FL. (good god, I'm dating myself as an old timer in this profession, LOL) and10 + years ago and as recently as 5 years ago we did a LOT of Tile roofs, and back then mainly flat white concrete tile, but also terra cotta barrell tile as well and also used to Down Stream the Love (SH) and surfactant and Surface Cleaner Technique.
We had several Diesel Fired Hot Water Pressure Cleaners from DELCO out of Ft. Worth, TX running at 5 @ 3000psi.
Using the Hot Water, with the surface Cleaner technique, it cleaned pretty well, actually, and after mastering how NOT to hit the tiles with the rotating tips and Learning how to wrestle the deck of the surface cleaner to where it stayed flat on the tile surface, it made for some SORE backs, abs and arms in those days.
But , you know what? It was what we knew at the time and got the job done ( the old Delco board was just starting to BUZZ about new roof cleaning methods back in the day and Chris Tucker, of Apple Roof Cleaning was one of those pioneers trying different alternative methods)
Back then, except for the occasional tile breaking (we had a clause in our agreement stating the HO may have to pay for tile repairs and we ALWAYS carried Roof Mastic and the BIG Tubes of Tile Roof Repair Caulking) as it was considered by many as the normal way to effectively clean tile roofs back in the day. (Glad we have since found
a better, safer way to gently clean Asphalt Shingle and Tile Roofs )
There was and believe, still is, a company called ICCES down in Ft. Lauderdale, FL. who were also pioneers of the Low and No- Pressure Cleaning methods, as I remember, they turned me onto the concept of chemical cleaning by actually letting US use one of the 1st 15 GPM @ 100 psi rigs they built in 2001 using the low pressure rinse method with a product called Revive-All, a contractor only roof cleaning compound and Large capacity diaphragm pumps.
Now, as I have been re-branding the business up here in South Georgia, as Roof Clean USA over the course of the last couple of years, mainly ultra low or non-pressure roof cleaning is all we do, along with traditional pressure cleaning of many surfaces around the home and business.
Non-Pressure is the way to go for CLEANING roofing systems. It's safer and It WORKS.
And because the industry as a whole and most importantly, the HO and commercial property owner is more aware of the options available to them for safely contracting out roof cleaning to contractors we have had to evolve with the changes, methods and safe roof cleaning practices.
The industry has matured and grown up a lot in the last few years, and I, for one, am all for it.