ollow your pressure washer’s instructions and hose, trigger gun. Start the pressure washer and attach the green 25 degree 60 GPM nozzle. Make sure that every time you change nozzles that your quick connect is fully engaged. If it is not fully engaged and “locked” the nozzle will shoot off the end of the lance when you squeeze the trigger and you could possibly lose the nozzle or break a window.

Remember to always point the wand in a safe direction before first pulling the trigger, the initial “burst” of pressure is greater with the first pull and then is reduced to a steady flow. If you are aiming at something, this burst could possible damage it or cause you to lose balance.

Pre-wet any plants that are below the area to be washed, aim above the plants at a distance and allow the mist of the spray to wet the plants. Don’t aim the pressure washer directly at the plants or get too close otherwise you will damage the plants.

Place the detergent injector in the 5 gallon bucket of detergent “House wash” mix. Attach the 25 degree soap 60 tip to the pressure washer, move closer to a the siding away from any plants and spray the wall until the chemical injector draws detergent, you should be able to tell by the soap bubbles.

Start from the bottom and apply the detergent to the siding as far up as you can reach. Then switch to 0 degree 60 nozzle to reach the higher areas of the siding and the fascia. Make sure all the siding is covered with the detergent. You do not have to “saturate” the surface, just “wet” the surface with the detergent. The secret of efficient washing is multiple quick applications, not long saturating applications that just waste detergent on the ground. Then switch back to the “Green” 25 degree 60 orifice nozzle and spray the siding away from plants to empty the detergent from the lines.

Then immediately rinse any windows from a distance to prevent the solution from drying on the windows. Never spray windows up close with pressure, this can break the vapor barriers of the windows causing them to fog. Always rinse the windows at a distance with low pressure.

Once approximately 5 minutes have passed, apply a second application of “House Wash” mix to the siding. You can move faster now that you are re coating the surface. Pros will coat a larger area (two sides of a small to medium house), then walk back to the start for the 2nd application. By the time they have finished the 1st application, the starting area is ready for the 2nd application and no time has been wasted.

You should see the mold begin to turn brown and run down the siding, if there any areas still containing mold after a few minutes reapply the detergent solution to those areas. If there are any very stubborn mold spots you can use pressure up close to remove them, or use a brush or rag if you can reach the area. Also note our solution will only effectively remove mold, if there are clay stains, grease stains, or heavy dirt stains on the siding you may have to switch to a stronger soap solution or brush the area to remove the stains.

After two applications of “House Wash” check the gutters and siding for any stubborn mold spots that remain. If you still see mold, switch the detergent injector to the “Strong Wash” bucket and spot clean the mold areas only. You can use the 0020 tip to clean the outsides of metal gutters to remove stubborn mold, be careful not to hit the shingles or siding with that tip. You can also use a brush to speed up removal of stubborn areas on gutters and siding while not waiting for the SH to work.

Heavy clay and rust stains need an acid based detergent for removal, OneRestore by EaCo Chem is the best that we have found, however it is expensive at $20/gallon or $100/5 gallons and you must use it straight or 1:1 applied with a pump sprayer. Note you cannot mix acid based detergents with alkaline detergents such as soaps or SH.

If the detergent does seem to be removing the mold by itself, you can increase it’s strength by adding more SH to the mix. SH has a limited shelf life and can lose strength over time or if exposed to sunlight. Experiment until it begins cutting through heavy layers of mold by itself, with soft washing the detergents alone should do the cleaning, you shouldn’t have to use up close pressure to remove the mold and mildew.