Revitalize Your Deck: The Homeowner’s Guide to Deck Cleaning 

composite decking material

Contact Hydro Force For A Free Quote

Don’t let dirt and grime tarnish your home’s appearance. Get a free estimate from Hydro Force now, and step into a cleaner, brighter space. Your satisfaction is our guarantee. Contact us today!

The Homeowner’s Guide to Deck Cleaning with Sodium Hydroxide and Oxalic Acid


Deck maintenance is one of those homeowner responsibilities that often gets pushed to the back burner. However, leaving your deck uncared for can lead to a myriad of problems, including mold, mildew, and even structural issues. Cleaning your deck not only maintains its aesthetics but also prolongs its lifespan, ensuring that you can enjoy those sunny day barbecues and cool evening lounges for many years to come.

In this guide, we’re diving deep into the world of deck cleaning, exploring two powerful cleaning agents – sodium hydroxide and oxalic acid – that can help you revitalize your deck, making it look brand new. Whether you are a seasoned homeowner or just starting, this guide will walk you through everything you need to know about these cleaning agents and how to use them effectively. So roll up your sleeves and let’s get started!

Section 1: Understanding Your Deck Material

Before we delve into the nitty-gritty of deck cleaning, it is essential to understand the type of material your deck is made from. Different materials respond uniquely to various cleaning agents, and knowing your deck’s composition can save you from potential damages during the cleaning process.

Different Types of Deck Materials

Traditional decks are predominantly made of wood, ranging from pressure-treated lumber to exotic hardwoods. Wood decks have a natural and warm aesthetic but are prone to discoloration and damage from the elements.

deck pressure washing near me


Composite decks, on the other hand, are crafted from a blend of wood fibers and plastics. These decks are known for their durability and resistance to moisture, but they can harbor stains and mildew over time.

Understanding how these materials respond to cleaning agents will inform your choice of sodium hydroxide or oxalic acid for the cleaning process.

composite deck cleaning

Section 2: Introduction to Sodium Hydroxide and Oxalic Acid

As we embark on the cleaning journey, it’s pivotal to acquaint ourselves with the two heroes of our story: sodium hydroxide and oxalic acid. These substances, widely used in the cleaning industry, come with their sets of benefits and precautions.

What is Sodium Hydroxide?

Sodium hydroxide, also known as lye, is a robust base used in various applications, including cleaning. It has a remarkable ability to break down stubborn stains and grime, making it an excellent choice for deep-cleaning your deck. However, it’s potent and requires careful handling to avoid damages to your deck and surrounding vegetation.

What is Oxalic Acid?

Oxalic acid, a natural compound found in many plants, is another powerful cleaning agent. It is particularly adept at removing rust and iron stains, making it a fantastic option for reviving old and weary decks. It can brighten wood surfaces, restoring them to their original beauty.

Safety Measures When Handling These Substances

Safety cannot be overstated when using potent cleaning agents. Always use gloves and eye protection, and ensure to work in well-ventilated areas to avoid inhaling any fumes. Moreover, keep pets and children at a safe distance while you work.

As you gather your cleaning agents, it’s also a good practice to cover surrounding plants and vegetation with plastic sheets to protect them from potential spillage and the effects of the cleaning agents.

Section 3: Getting Ready for Deck Cleaning

Gathering Your Materials

To kickstart your deck revitalization project, it is essential to gather all the necessary materials first. Here is a checklist of what you will need:

  • Sodium hydroxide
  • Oxalic acid
  • A bucket for mixing solutions
  • A stiff-bristle brush or a broom
  • Protective gear such as gloves and goggles
  • Garden hose with a high-pressure nozzle or a pressure washer

Ensure that you have all these materials on hand to make the cleaning process smooth and hassle-free.

Protecting Your Garden and Surrounding Areas

Before you start the cleaning process, take time to protect your garden and other surrounding areas. Cover plants, outdoor furniture, and other items with plastic sheets or tarps to shield them from the chemicals. It’s a preventive step that will save you from witnessing damaged plants and corroded items later on.

Deck Inspection

Inspect your deck thoroughly to identify any areas that require repairs. Look out for loose boards, popped nails, or other potential hazards. Fixing these issues before cleaning ensures a safe cleaning process and enhances the deck’s overall appearance post-cleaning.

Section 4: Deck Cleaning Step-by-step Guide

Step 1: Pre-cleaning Preparation
Clearing the Deck

Start by removing all furniture, grills, and other items from the deck. Sweep the deck thoroughly to get rid of leaves, dirt, and debris. A clean surface allows the cleaning agents to work more effectively.

Safety Gear

Equip yourself with the necessary safety gear, including gloves and goggles, to protect yourself from the chemicals. Wearing old clothes is advisable as the cleaning agents can bleach or damage the fabric.

Step 2: Creating Your Cleaning Solutions
Recipe for Sodium Hydroxide Solution
  • Sodium hydroxide: 2 cups
  • Water: 4 gallons

Mix the sodium hydroxide and water in a large bucket, stirring until fully dissolved.

Recipe for Oxalic Acid Solution
  • Oxalic acid: 1 cup
  • Water: 2 gallons

Just like the previous solution, mix the ingredients in a large bucket until the oxalic acid dissolves completely.

Note: Always add the chemical to water and not the other way around to prevent reactions.

Step 3: The Cleaning Process
Applying the Cleaning Solutions

Using a brush or broom, generously apply the sodium hydroxide solution onto the deck, focusing on heavily stained areas. Let it sit for 15-20 minutes, allowing it to break down the stains and grime.

Next, rinse the deck thoroughly with water before applying the oxalic acid solution using the same technique. Allow it to sit for 15-20 minutes to work on brightening the wood.

Scrubbing the Deck

Scrub the deck vigorously with a stiff-bristle brush to remove stubborn stains and dirt. Work in sections to ensure even cleaning.

a stiff bristled deck brush

Step 4: Rinse and Neutralize
Proper Rinsing Techniques

After scrubbing, rinse the deck thoroughly using a garden hose with a high-pressure nozzle or a pressure washer on a low setting. Ensuring all residues are washed off is vital.

Neutralizing the Chemicals

To neutralize the chemicals and restore the pH balance of the wood, rinse the deck with a baking soda solution (1 cup of baking soda mixed with 2 gallons of water) after cleaning with the chemicals.

Step 5: Drying and Inspecting
Drying Time

Allow the deck to dry completely, which might take up to 48 hours. Refrain from stepping on the deck during this time to prevent marks and stains.

Inspecting Your Work

Once the deck is dry, inspect your work. You might notice a significant improvement, with your deck looking almost as good as new. Take note of any areas that might need a touch-up or further treatment.

deck pressure washing near me deck pressure washing near me

Section 5: Troubleshooting Common Issues

As with any home maintenance task, you might encounter some challenges during your deck cleaning process. Here, we provide solutions to common issues that may arise.

Addressing Stubborn Stains

Even after a meticulous cleaning, some stains may prove stubborn. For such areas, prepare a concentrated solution of the cleaning agent and apply it directly to the stain, allowing it to sit for a few minutes before scrubbing vigorously.

What to do with Discolorations

Discolorations can sometimes occur, especially on wood decks. If you notice uneven coloring after cleaning, consider using a wood brightener. These products can even out the tone and bring back the natural beauty of the wood.

Fixing Minor Damages

Minor damages like scratches or small dents can occur during the cleaning process. Sanding the affected areas lightly and then sealing them can usually remedy this. Remember to always move in the direction of the wood grain to prevent further damage.

Section 6: Post-cleaning Deck Maintenance

Now that your deck looks fresh and revitalized, maintaining its beauty should be your next focus. Let’s look at how you can keep your deck looking great year-round.

Sealing Your Deck

Sealing your deck is a vital step to ensure its longevity. Choose a high-quality deck sealer to create a barrier against moisture and UV rays. Apply the sealer evenly, following the manufacturer’s instructions for the best results.

Regular Maintenance Tips
Sweep Regularly

Regular sweeping prevents the accumulation of dirt and debris, which can lead to mold and mildew. Make it a habit to sweep your deck regularly to maintain its cleanliness.

Quickly Address Spills

Spills can cause stains, which can become permanent over time. Address spills as soon as they happen to prevent staining.

Annual Inspection

Undertake an annual inspection of your deck to check for any signs of wear and tear. Regular inspections can help in identifying problems early on, making them easier and cheaper to fix.

When to Call a Professional for Help

While DIY cleaning is great, there are times when calling a professional is the best option. If you encounter severe structural issues or persistent problems that you cannot solve, don’t hesitate to call a professional deck cleaning service.



Revitalizing your deck is not just about maintaining its aesthetic appeal but also about ensuring its longevity. With this comprehensive guide, we hope you are well-equipped to undertake a successful deck cleaning project using sodium hydroxide and oxalic acid. Remember, the joy of a revitalized deck is worth every bit of effort put in!

Contact Us For A Free Estimate


You May Also Like…