Quick answer: Cleaning a house exterior, whether stucco, siding, or painted walls, calls for a fundamentally different approach than cleaning a driveway. High pressure water can crack stucco, strip paint, or force water behind siding, so the correct method is generally a soft wash, low pressure water paired with a cleaning solution that breaks down algae and mildew at the source rather than relying on force.
Key Takeaways
- High pressure is the biggest risk to a house exterior, since it can damage stucco, siding, and paint that a driveway would easily tolerate.
- Soft washing, low pressure combined with a cleaning solution, is the standard, safer method for these surfaces.
- North facing walls and shaded areas tend to collect mildew faster and may need more frequent attention.
- Working at height, especially on a second story, introduces real safety considerations beyond the cleaning technique itself.
- Cleaning the exterior thoroughly before repainting is essential, since paint applied over dirt or mildew fails early.
What Equipment Do You Need to Clean a House Exterior?
A pressure washer capable of running at low pressure settings, ideally with a wide fan tip nozzle rather than a narrow, concentrated one, along with a soft wash cleaning solution formulated for exterior walls rather than a concrete specific product. An extension wand can help reach higher sections of the exterior without needing a ladder for every pass, and a garden hose for a final gentle rinse is useful as well.
Step by Step: How to Clean Your House Exterior Yourself
1. Identify Your Exterior Material
Confirm whether your home is stucco, vinyl siding, fiber cement siding, or painted wood before starting, since this affects both the cleaning solution and the pressure setting you should use throughout the job.
2. Protect Windows, Outdoor Fixtures, and Landscaping
Close windows and doors, cover any sensitive outdoor fixtures or electrical components, and wet down landscaping directly bordering the house before applying any cleaning solution.
3. Apply the Cleaning Solution at Low Pressure
Apply the soft wash solution evenly across the wall in manageable sections, working from the bottom up to avoid streaking, and allow the recommended dwell time on the product, generally around 10 to 15 minutes, before rinsing.
4. Rinse Gently From the Top Down
Rinse in the opposite order from application, working from the top down, using low pressure and a wide fan pattern rather than a narrow, concentrated stream. Keep the nozzle at a distance and avoid spraying directly into seams, vents, or window and door trim.
5. Pay Extra Attention to North Facing and Shaded Walls
These areas often hold more mildew than sun exposed walls and may need a second pass or slightly longer dwell time to fully address.
6. Let the Exterior Dry and Inspect the Results
Once dry, check for any remaining staining or streaking, and confirm no cleaning solution has pooled or left visible residue anywhere on the surface.
Common Mistakes to Avoid
| Mistake | Why It Causes a Problem |
|---|---|
| Using driveway level pressure on siding or stucco | Can strip paint, crack stucco, or force water behind siding into the wall itself |
| Spraying directly into seams, vents, or window trim | Can push water into places it is not meant to go, leading to hidden moisture problems |
| Skipping the cleaning solution and relying on pressure alone | Often leaves mildew and algae only partially removed, with quick regrowth afterward |
| Working from the top down when rinsing | Rinsing should generally move top down after a bottom up application to avoid streaking, so reversing this order can leave visible streaks |
When Should You Call a Professional Instead?
Short answer: DIY exterior cleaning can work for a single story home with straightforward siding or stucco in reasonably good condition. Two story homes, older stucco with existing hairline cracks, or any exterior with significant mildew buildup are situations where professional experience becomes genuinely valuable.
The stakes on a house exterior are higher than on a driveway, since a mistake here can mean stripped paint, damaged stucco, or water intrusion that costs far more to fix than the cleaning itself. Working safely at height on a two story home adds another layer of risk that goes beyond the cleaning technique. For many homeowners, the combination of technique sensitivity and physical safety makes this one of the more worthwhile jobs to have handled professionally.
If you would rather have your house exterior handled professionally, our house exterior and siding pressure washing page covers our soft wash approach for stucco, siding, and painted surfaces.
Frequently Asked Questions
Can I pressure wash my house myself without damaging the paint?
Yes, if you use a soft wash approach, low pressure combined with a cleaning solution, rather than high pressure water aimed directly at the painted surface. High pressure is what typically causes paint to strip or peel prematurely.
What is the difference between pressure washing and soft washing a house?
Pressure washing relies primarily on force to remove dirt and staining, while soft washing uses low pressure combined with a cleaning solution that breaks down algae and mildew at the source. Soft washing is the standard, safer approach for stucco, siding, and painted surfaces.
Is it safe to clean stucco myself?
Yes, when using a low pressure soft wash method. High pressure water can crack stucco or force water behind the surface, so a gentler, more controlled approach is necessary for this material.
How often should I clean my house exterior?
Most homes benefit from a full exterior wash about once every one to two years, though homes with heavy shade or north facing walls that stay damp longer may need attention more frequently.
Should I hire a professional to clean a two story house?
Many homeowners choose to hire a professional for two story homes, since working safely at height adds real risk beyond the cleaning technique itself, and reaching upper sections evenly with the correct low pressure technique is more difficult without the right equipment and experience.