PSI guide
Choose the right pressure for Mid-Missouri exterior surfaces.
Safe working pressure depends on the material, its condition, the washer’s flow rate, nozzle size, spray angle, distance, and cleaning solution. Follow manufacturer guidance and test a hidden area before cleaning the full surface.
| Surface | General reference range | Tip or method | Field notes |
|---|---|---|---|
| Concrete driveway | 2,500-3,500 | Surface cleaner or 25 degree tip | Pre-treat oil, rust, and tire marks. Keep passes even to avoid striping. |
| Sidewalks and patios | 2,000-3,000 | Surface cleaner or 25 degree tip | Rinse toward drainage. Watch edges, joints, and nearby doors. |
| Pavers | 1,500-2,500 | 25 or 40 degree | Avoid blowing out joint sand. Rinse at a shallow angle. |
| Vinyl siding | 500-1,200 | Soft wash or 40 degree rinse | Apply cleaner at low pressure and rinse downward. Do not drive water behind laps. |
| Painted wood | 500-1,000 | 40 degree | Test carefully. Too much force strips paint and raises grain. |
| Composite deck | 800-1,500 | 40 degree | Follow manufacturer guidance. Skip turbo tips and narrow streams. |
| Natural wood deck | 500-1,000 | 40 degree | Use wood cleaner, low pressure, and steady passes with the grain. |
| Brick in good shape | 500-1,500 | 25 or 40 degree | Check mortar first. Older brick may need soft washing, not blasting. |
| Outdoor furniture | 500-1,000 | 40 degree | Use low pressure on fabric, wicker, paint, and aged wood. |
Important: These figures are general reference ranges. Pressure at the surface changes with nozzle size, flow rate, working distance, equipment, and surface condition. Manufacturer instructions take priority. Test a hidden area and stop if the material changes.
Siding and painted surfaces
Begin with inspection and detergent.
Inspect for oxidation, loose panels, damaged seals, peeling paint, and exposed fixtures. Apply a surface-appropriate detergent at low pressure and keep rinse water away from laps, vents, outlets, lights, and window seals.
Request an assessment for:
- Roofs or second-story siding
- Oxidized vinyl or aluminum
- Stucco, EIFS, or old masonry
- Lead paint risk or peeling paint