To maintain a slate roof and prolong its lifespan, conduct regular inspections, ideally annually, or schedule professional inspections. Key maintenance includes cleaning gutters regularly, promptly replacing any broken or damaged tiles, and ensuring the flashing remains intact to prevent leaks. It is also recommended to remove overhanging tree branches and address minor issues as soon as they appear.

Soft washing chemicals typically consist of a mix of sodium hypochlorite (or a chemical component of bleach) and water. While sodium hypochlorite and bleach are often thought to be the same thing, there is one small but key difference between the two: sodium hypochlorite comes in powdered rather than liquid form, which means that it’s also more concentrated and more effective from less product overall.

You should avoid using a pressure washer on any surface or item that could be damaged by the high-pressure spray, as some materials are too delicate to withstand the force.

Key items and surfaces to avoid include:

• Electrical Components: Never pressure wash electrical systems, as water can cause short-circuits and create a safety hazard. This includes utility meters, breaker boxes, electrical outlets, generators, and HVAC or air conditioner units.

• Delicate and Fragile Materials: Fragile items can crack, shatter, or be stripped by the pressure. Avoid pressure washing windows, glass, light fixtures, shingled roofs (especially asphalt), and stucco.

• Painted, Stained, or Sealed Surfaces: Unless your goal is to strip the finish, do not pressure wash painted surfaces, stained wood (like decks), or anything with a protective seal that could be stripped away. Be especially cautious with older surfaces that may contain lead paint.

• Soft Woods and Certain Decking: Delicate surfaces like softwood, composite decking, and antique or wooden patio furniture can be etched or damaged. If you must wash wood, use a lower-powered pressure washer with a wide-angle nozzle to prevent damage.

• Living Things: Never use a pressure washer on people, pets, or plants. The force can cause serious injury and will destroy landscaping.

Having your roof cleaned can be worth it because it improves the life span of the materials on the roof. You won’t have to pay a roof replacement cost as often when you clean the roof regularly.