Powerful House Washing with 12.5% Sodium Hypochlorite

Powerful House Washing with 12.5% Sodium Hypochlorite

Get the best results with the right product and the right method

If you want a clean, bright home exterior, 12.5% Sodium Hypochlorite (SH) is one of the most effective solutions on the market. This professional-grade bleach is widely used by soft washing and pressure washing professionals to remove mold, mildew, algae, and other organic stains from siding, stucco, brick, and more.

At Southern Maryland Outdoor Power Equipment, we keep fresh, high-quality 12.5% SH in stock for contractors and homeowners who want professional results.

Why Use 12.5% SH for House Washing?

  • Highly effective – Kills mold, mildew, and algae at the root

  • Fast results – See surfaces brighten within minutes

  • Professional strength – Stronger than store-bought bleach, so you can clean faster and more thoroughly

  • Versatile – Works on vinyl siding, stucco, brick, concrete, and more (when properly diluted)

How to Use 12.5% SH for House Washing

Important: Always wear gloves, eye protection, and old clothes when working with sodium hypochlorite. Protect nearby plants by rinsing them before and after cleaning.

  1. Dilute Properly

    • For house washing, a common mix is 1–2% SH on the surface.

    • This means you’ll need to dilute your 12.5% SH with water in a proportion that achieves the right strength for your application.

    • Example: Mix 1 gallon of SH with 5–6 gallons of water for siding cleaning.

  2. Add a Surfactant

    • Use a quality surfactant (soap) to help the solution cling to surfaces and break down dirt.

    • This prevents streaking and increases cleaning efficiency.

  3. Apply with Low Pressure (Soft Wash Method)

    • Use a soft wash system or downstream injector on your pressure washer.

    • Apply the solution from bottom to top to avoid streaking.

  4. Let It Dwell

    • Allow the mix to sit for 5–10 minutes, keeping it wet.

    • Do not let the solution dry on the surface.

  5. Rinse Thoroughly

    • Rinse from top to bottom with low to medium pressure.

    • Make sure all chemical residue is removed.

Pro Tips for Best Results

  • Work in the shade – Direct sunlight can dry your mix too quickly.

  • Pre-wet plants & landscaping – Reduces the risk of damage.

  • Use fresh SH – Old sodium hypochlorite loses strength over time. Always buy from a trusted supplier who stores it properly.

Where to Buy Fresh 12.5% SH in Southern Maryland

We sell fresh, contractor-grade 12.5% sodium hypochlorite in convenient sizes so you can get the job done right. Whether you’re a weekend warrior or a full-time pressure washing contractor, we have what you need to keep homes looking spotless.

📍 Southern Maryland Outdoor Power Equipment
2205 Crain Hwy, Waldorf, MD 20601
📞 301-396-3989