COLOR RESTORATION
Redwood, like other natural woods, will eventually change color in the elements. Factors such as sunlight, moisture, and dirt contribute to natural discoloration. Luckily, color restoration of redwood decks, fences, porches, and shade structures is not difficult.
First, begin with identifying the cause of discoloration. Mildew, extractive bleeding and iron stain are common causes. Mildew usually appears as dark spots on redwood’s surface. Severe mildew may be uniform and cover a large area. You can test for mildew by applying a drop of household bleach to the dark spots. If mildew is present, the spots will disappear in one to two minutes.
The process of color restoration to the original redwood color of the wood begins with scrubbing the wood surface with a mild detergent to remove any mildew. Next, rinse the surface with household bleach. Finally, rinse with water. To remove severe mildew, use a stiff bristle brush and scrub the wood with a solution of one cup of trisodium phosphate (TSP), one cup of household bleach and one gallon of water.
Extractive bleeding is another cause of redwood discoloration. Redwood contains naturally occurring chemical extractives, which are water soluble. If these extractives reach the wood’s surface, they may cause dark staining. Redwood color restoration for extractive bleeding is accomplished using oxalic acid. Wash the redwood’s surface with one cup of TSP and one cup of household bleach mixed in a gallon of water. Rinse thoroughly and follow with an application of four ounces of oxalic acid crystals dissolved in one gallon of warm water in a non-metallic container. When the wood dries thoroughly, rinse with clean water.
Redwood exposed to iron and water causes the naturally-occurring tannins to react, forming dark staining. This can happen in any species of wood with high tannin content. Redwood color restoration for iron stain can be accomplished using the oxalic acid solution described above.
FINISHING TIPS
Redwood is nature’s own maintenance-free building material. When it comes time to build your Redwood project, easy to follow finishing tips are available to get you started.
Finishes formulated for wood surfaces that contain UV protection and a mildewcide offer the most protection for your redwood projects. Wood stains are generally available in clear, semi-transparent, and solid color options. Clear stains will allow the natural color and grain of the redwood to show through. Semi-transparent stains are available in a variety of attractive colors to customize the look at feel of the project. Solid color stains are opaque and hold up the longest, however they do obscure the natural grain and color of the wood itself. Painting redwood structures is certainly an option as well.
Regardless of the finish you choose, completing regular maintenance and keeping redwood structures clear of leaves and other debris will make refinishing redwood easy. The following finishing tips provide additional information:
- If the wood is unseasoned, allow it to be exposed to the ambient air for at least a month before applying any finish.
- Apply finishes on windless days. Ideal temperature is between 50 and 70 degrees (Fahrenheit).
- Redwood surfaces should be clean and dry.
- Thoroughly ventilate the area prior to finishing application. Moisture is a frequent cause of ineffective finishes, so be sure the proper precautions against it are taken. This includes using air vents, vapor barriers, and flashing.
- If your project is outdoors, choose wood finishes recommended for outdoor use only.
- Avoid using abrasive, metal-based brushes, since they may react with the wood and stain it. Choose stiff-bristled, non-metallic brushes.
- Be sure any products you mix are meant to be used together. Mixing dissimilar finishes might result in failure of the finish.
- Always follow the manufacturer’s specific instructions for all products used.
- Prime the wood prior to applying paints or other external finishes.
- Choose the finest hot-dipped galvanized nails available. Opting for lower-quality nails may result in stains. Alternately, opt for nails made from aluminum or stainless steel.
- Periodic rinsing with a garden hose will remove surface dirt and grime.
- Stubborn, built-up dirt and grime can be removed by scrubbing with a bristle brush and a solution of warm water and a mild detergent. Rinse afterward.
REFINISHING VIDEO
Redwood deck expert, Jeff Imwalle, walks through all the steps needed to refinish a redwood deck like a professional. Jeff’s expert guidance will help even the most inexperienced homeowners or do-it-yourselfers get started refinishing their redwood deck.