Safety Disclaimer — Read Before Use
This is user-generated content, not professional chemical advice. Always wear proper PPE (gloves, eye protection, respirator as needed). Test any chemical mix on a small inconspicuous area first. Follow each product's SDS and label instructions — dilution ratios may vary by brand concentration. Comply with all local water runoff and discharge regulations. Some chemicals listed (acids, caustics, bleach) are hazardous if misused. The authors and Pressure Washing Cookbook assume no liability for outcomes.
House Wash — Vinyl Siding (Soft Wash)
Before / After Photos
Recipe Details
Target Surface
Vinyl, Aluminum, Stucco Siding
Problem / Stain
Algae / Mold, General Dirt
Chemicals / Products Used
| Product / Chemical | Function |
|---|---|
| Sodium Hypochlorite (SH) 12.5% | Active Cleaner |
| Surfactant | Surfactant / Wetting Agent |
Mixing Ratio / Dilution
1 part SH 12.5% : 3–4 parts water
≈3–4% final SH concentration. Add 2–4 oz surfactant per gallon of mix. Pre-mix in a dedicated tank.
Dwell Time
5–10 minutes — keep surface wet, do not let dry
Application Method
Low pressure (under 100 PSI) — downstream injector or dedicated soft wash pump
Apply bottom-to-top, rinse top-to-bottom. Pre-wet all plants and landscaping before AND after.
Safety Notes — Required Reading
Full PPE required: chemical-resistant gloves, eye protection, respirator if working in enclosed spaces. Protect all landscaping with thorough pre-wetting and post-rinse. SH will bleach fabric — wear dedicated work clothes. Contain runoff — bleach is toxic to aquatic life. Check local discharge regulations before rinsing.
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Staff-Seeded Starter Recipe
This is a staff-seeded starter recipe sourced from industry suppliers, trade publications, and contractor forums. It represents widely-used, publicly documented mixing formulas as general starting points — not any single brand's proprietary formula. Always verify against your specific product's SDS and label.
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Contractor Comments (37)
Marcus T.
Titan Wash Co. · Atlanta, GA · 2026-08-10
Solid ratio for typical house washes. I bump up to 1.5% SH when dealing with heavy green algae on north-facing walls. Also, Elemonator as the surfactant makes a huge difference in dwell time vs generic dish soap.
Deja W.
· 2026-08-11
Agreed on Elemonator. I also add a bit more surfactant in hot weather since it evaporates faster.
Kyle B.
WashPro · Phoenix, AZ · 2026-08-05
In Arizona heat I have to be really careful about dwell time — 5 minutes max in summer or it bakes on. Pre-wet everything twice as much as you think you need to.
Sandra M.
ProClean Services · Tampa, FL · 2026-07-28
This is my go-to recipe. One thing I'd add: for stucco with heavy organic staining, bump to 4% and let it dwell 12 minutes. Rinse really well — stucco holds SH longer than vinyl.
Submitted By
Official Starter
PW Cookbook Staff
National
Recipe Stats
