With its inherent dimensional stability and heartwood decay resistance, redwood lumber is one of few wood species that can be allowed to weather naturally. This no-maintenance option results in a look often preferred for a rustic weathered appearance. Years of testing by the U.S.D.A. Forest Products Laboratory have shown that redwood is among a group of woods that erode at only 1/4 inch of wood fiber per century in unfinished exterior applications. Because of these qualities, many centuries-old redwood homes and other redwood buildings now being recycled and renovated, have been found to be in excellent condition, requiring a minimum of structural repair or replacement of siding or trim.
Color changes due to weathering
As redwood weathers, several natural color changes take place. These changes may occur over a period of years and will vary from one climate to another. In a damp or humid climate, redwood lumber used outdoors will go through two stages, the first being a darkening of the wood. As time goes on, this darkening may be rinsed away by rain and the redwood will weather-bleach to a soft driftwood gray. A redwood structure sheltered from rinsing rains may remain dark throughout its lifetime. Therefore, the site of the structure plays an important part in the decision to leave the redwood unfinished. In drier climates, unfinished redwood may not darken. Instead, the wood will gradually turn a silvery tan, becoming lighter in color as the natural weathering continues.
Infinite variations of color
The effects of natural weathering will not be the same on all sides of a house. This is because redwood’s color changes are caused by sunlight and water, and different areas of a house usually are exposed to different amounts of each. Two boards installed side by side may also vary in color because of the infinite variations of color and texture offered by redwood lumber. This is one of the refreshing, inherent qualities of a natural material such as redwood, compared to the artificial uniformity of synthetic products.
Reversing color changes
These natural color changes, a result of the weathering process, are completely reversible. Visit our Redwood Color Restoration page for more information. If you decide to refinish your redwood project, take a look at our Redwood Finishing Tips page to find the right paint or stain for your redwood structure.