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Cleaning Wood Siding – Be Gentle – Pressure Causes DAMAGE

natural wood siding

Cleaning Wood Siding This wood siding can be cleaned with certified organic STAIN SOLVER. It's oxygen bleach. Cleaning outdoor wood is not hard to do at all.

Cleaning Wood Siding - Beware Pressure Washers!

DEAR TIM: We live in a shady wooded area. Our house is covered with natural cedar wood siding that constantly develops mildew stains. Every few years we apply an additional coat of oil-based semi-transparent stain to make the house look fresh. What products are best to use to clean the siding and to seal it? How long will a good water repellent last? Do you have cleaning wood siding tips for me? Susan P., Highland Park, IL

DEAR SUSAN: It's no wonder you have mildew problems on the siding. I want to warn you now to never use a pressure washer to clean your siding before you next seal it. Watch this video to see the damage pressure washers cause.

What Causes Mildew on Wood Siding?

Mildew on wood siding is caused by mold spores that float onto the siding. They eat dust and wood sealers and water activates the mold spores creating the mildew

Millions of mold spores are in the air surrounding your house. They land on the siding and once there are delighted to find out that you have provided them with dinner.

Do Oil-Based Stains Contain Natural Oils?

Many oil-based house stains contain natural oils and resins like:

  • linseed oil
  • vegetable oil
  • tung oils
  • animal fat

Are Natural Oils Food For Mildew and Mold?

Yes, the natural oils found in many wood sealers and water repellents are food for mildew and mold.

These water repellents happen to be food that mildew thrives on. The shady conditions slow natural evaporation and help to raise the overall humidity around the siding. These conditions are excellent for mildew growth.

Do the Manufacturers Know the Oils Feed Mildew?

Yes, the manufacturers of many exterior stains know this. They add chemical mildewcides and fungicides to the stains. But ultraviolet (UV) rays from sunlight and rainwater break these chemicals down. Some stains contain very little of these products and within a short amount of time, the mildew can start to grow.

What is the Best Wood Sealer?

In my opinion, the best semi-transparent stain to use is one that contains no natural oils. I prefer to use products that are made with synthetic resins.

cabot australian timber oil

This is the best penetrating wood sealer I know of as of 2021. CLICK on THE IMAGE to have it delivered to your home.

Does Mildew Eat Synthetic Resin?

Mildew will not eat synthetic resin. It's still possible to get a small amount of mildew growth on the siding but the food source usually can be traced to airborne dust or aerosol saps and sugars that rain down from your trees during the active growing season.

How Do You Deep Clean Wood?

You deep clean wood using certified organic STAIN SOLVER. It's an oxygen bleach made in the USA. It will not damage the wood and it's not harmful to vegetation. You use the exact same product for mold removal on vinyl siding.

Stain Solver black background yellow scoop

Stain Solver is MADE in the USA with USA ingredients that are food-grade quality.

Before you apply any water repellent to the siding, you must deep clean it to get the best results. Avoid cleaners that contain chlorine bleach. You can readily identify this by looking at the product label. The chemical name for chlorine bleach is sodium hypochlorite. This chemical can readily bleach the gorgeous natural color from your siding. It is also highly toxic to vegetation and your valuable trees. A neighbor of mine slowly killed one of her trees by using chlorine bleach to clean a patio each spring.

What is a Safe Wood Cleaner?

A safe deep cleaner for wood siding is oxygen bleach. It is a powder that mixes with water. It is non-toxic to vegetation and trees and will not remove any natural color from the siding. You simply keep the wood siding wet with the oxygen bleach solution for 15 minutes. It will remove the mildew and deep clean the siding. Lightly scrub the siding before rinsing with clear water from a garden hose. Avoid the temptation of using a pressure washer. These devices can force water into cracks and seams. This water gets behind the siding and can travel into your home. The intense pressure from these tools can quickly erode and scar soft woods like cedar and redwood.

How Long Can a Wood Sealer Last on Siding?

A top quality wood sealer and water repellent can last up to five to seven years before it needs an additional coat. These same products can be used on wood decks but will not last as long. The orientation of the siding on your home helps extend the life of the water repellent.

Why Do Wood Sealers Last Longer on Vertical Surfaces?

Wood sealers last longer on vertical surfaces because water runs off and the harsh mid-day ultraviolet rays of the sun give the wood a glancing blow, not a direct hit as they do with horizontal wood on decks.

Rainwater runs off the siding. When the sunlight does hit your house the intense mid-day UV rays glance off the siding. Because deck lumber lies flat, water readily soaks into the lumber and the UV rays at high noon blast the wood with a direct hit.

Is Price a Good Barometer When Buying Wood Sealer?

Price is a good barometer for judging water repellent quality. The synthetic resins contain very expensive raw materials. When you are doing comparative shopping, look for the highest priced product. It very likely is made with synthetic resins.

Where Do You Find the Best Wood Sealers?

I'd shop specialty paint stores or buy wood sealers online.

I have had the best success finding these water repellents at specialty paint stores and some log cabin distributors. Oxygen bleach is readily available on the Internet at www.stainsolver.com. Be sure to buy oxygen bleach that has the highest concentration of the active ingredient - oxygen bleach.

BEWARE OF LOW-COST Oxygen Bleach: Many of the well-known oxygen bleach products contain a significant amount of fillers that simply take up space in the container. Furthermore, many of the heavily advertised oxygen bleaches are made in the Far East, not in the USA!

Message from Tim:

Years ago while researching a column about cleaning decks, I discovered the wonders of Oxygen Bleach. It is perhaps the 'greenest' cleaner I know of as it uses oxygen ions to break apart stains, dirt and odor molecules. There are no harsh chemicals, and it works on just about anything that is water washable.

I decided to create my own special blend using ingredients made in the USA. In fact, the raw materials in the active ingredient are food-grade quality registered with the FDA. I call my product Stain Solver. I urge you to use it to help with your wood siding cleaning. You will be amazed at the results!

I'm proud of my product and have no trouble promoting it in my columns because I know it works. I know it's the BEST oxygen bleach you can buy. Not many entrepreneurs can say that about their product.

If you're a customer of mine and have used Stain Solver, please feel free to leave a comment below and tell the world what you think of Stain Solver. I thank you in advance.

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