How To Clean Your Wood With Sodium Hydroxide

Josh Richards • Feb 09, 2023

You're missing out if you haven't cleaned your wood recently. It is important to clean out your wood every year, especially when the end of the calendar approaches. Even the hardiest of exterior woods are at the risk of getting mold, mildew, and moss that can leave your wood in pretty bad shape. But it doesn't have to be that way! There are several ways you can clean your wood without renovating it.

But doesn't it feel like cleaning your exterior wood is a hassle? And isn't it a chore to be done if you want to prolong the lifespan of your wood? Well, all those thoughts are right! We're here to tell you how simple and easy it can be to clean your exterior wood. All you need are the right tools and basic household chemicals to clean your wood properly. 

While there are many options for such substances on the market, this article will focus on sodium hydroxide because the most common chemical used in professional wood cleaning products is sodium hydroxide (NaOH), which has proven to be the most effective product.

Sodium Hydroxide as a wood cleaner

Most people are familiar with sodium hydroxide as a cleaning chemical, which may be from its other common names, lye, and caustic soda. It is also commonly used as a drain cleaner. Suppose you are familiar with sodium hydroxide and have worked with it before. In that case, you might know this as a powerful, corrosive chemical that can remove stains from surfaces that other common cleaners cannot.

Because it does not need to be sprayed with high pressures to be effective, sodium hydroxide is the most common exterior wood cleaning solution. The chemical does most of the cleaning, a single good cleaning with this chemical is more effective than several sub-par ones. It can remove most stains and mold from the weathered wood surface.

Everything You Need to Know About Sodium Hydroxide

Wood Cleaning With Sodium Hydroxide

Gather all the equipment that you are likely to need:

Preparation

Remove any object placed in the surrounding wood, including flowerpots, furniture, etc. Large debris and dirt can be removed using a broom or by hand. Any visible damage to your wood, such as missing boards, broken screws, or decaying/ rotten wood, should be repaired. To prevent electrocution, cover all electrical outlets.

Safety Precautions

Many wood cleaning strippers can be dangerous if swallowed or come into contact with your skin. Use gloves, eye protection, skin protection, and a respirator to protect yourself. Before starting your wood restoration project, read the safety warnings and manufacturer's instructions. This chemical can also kill grass and plants and stain siding and glass.

Notice: It is highly recommended that you seek professional help if you have questions about using this product. This product must not be handled carelessly.

How to apply cleaning chemical

A mild solution of Sodium Hydroxide with a good surfactant can be applied to the wood if there is no sealer already present. The solution should be allowed to be absorbed in the wood. This will allow the mixture to soften the degraded wood and surface contaminants. A scratch test can be done to determine the ease of wood cleaning. It will be necessary to apply more of the mixture and allow for a longer dwell time if it is difficult to remove. A pressure washer can be used to remove any remaining stain, such as mildew or grill grease, and any other contaminants, such as flower pot stains, mold, and so on.

Method of application

You can either use down streaming, or you can apply chemicals directly using a battery-powered pump. The job's toughness will determine the application method. Pump spray allows for a higher concentration cleaner or stripper for more difficult sealers. Pressure washers can be used to downstream chemicals for transparent and semi-transparent stains.
The downstream process involves drawing chemicals through an attachment at high-pressure supply lines. Most downstream attachments draw between 10-1 and 20-1 (20 gal water to one-gallon cleaning solution). You will need to use specific pressure washer tips to allow the injector to create suction. You can also use a standard mop and bucket to apply high concentrations cleaners instead of a battery-powered pump.

Note: Use a pressure washer with care. Untrained pressure washer users can cause irreversible damage to wood, resulting in costly replacement of handrails or wood boards. In reality, you need less than 1000 psi/pressure. Water volume is more important than water pressure. More water equals more cleaning and rinsing power. To properly remove unwanted material, a minimum of 4 GPM is required. This excludes most pressure washers for homeowners, which typically rate less than 3 GPM (gallons per hour).

Strong and caustic nature

Your wood will likely turn black after you have cleaned it. You can fix this by using a low-pH brightness to neutralize the wood (to restore its pH), or weak acids like citric acid or oxalic acid. This will bring it back to the original color. Even if the wood isn't discolored, you should always neutralize it after cleaning with sodium hydroxide. The caustic base makes wood deteriorate and rot more quickly than it would otherwise. To prolong the wood's life expectancy, seal it with a good sealant after you have finished cleaning. You'll find sodium hydroxide in Thompson's Water Seal Maximum Strength Deck Stripper and other commercially available products.

Tip: Never combine water and Sodium Hydroxide. Mix the chemical in the water slowly and carefully. Mixing water first into chemicals creates a large amount of heat and fumes, resulting in a reaction.

Professional wood cleaning and Refinishing

We can't promise that there is one perfect solution or chemical that works for every job. We can promise knowledge of wood species, sealers, and popular chemicals and their effects on woo. We consider all the factors when determining the best course of action for wood restoration.

For wood restoration, it's best to go with the conservation rule. This means you use the least amount of treatment possible and get acceptable results. If you're looking for a professional for wood restoration in Orlando, FL, please call us at +1 407-222-4058.

FAQ

How do Water-Based & Chemical-Based Wood Cleaners Differ?

Alkaline cleaners are chemical-based products. These cleaners remove dirt, dust, and stains from wood. Water-based cleaners, on the other side, can be used for many purposes. They polish and clean surfaces without harsh chemicals. In contrast, chemical-based cleaners can more effectively remove tough stains from wood surfaces like mold and mildew than chemical-based cleaners. Water-based cleaners are gentler on the wood's surface and can be used to clean it later with soap and water.

What are the best deck cleaning chemical products?

Check our guide on Five best deck cleaners (INSERT LINK HERE) To learn more about the best cleaning wood chemicals read our guide (INSERT LINK HERE)