On 7/20/2016 9:15 PM, notbob wrote:
On 2016-07-20, Ed Pawlowski wrote:

I've had good results with cypress, spanish cedar, mahogany decking
material, and tiger wood. UV is the worst factor for it turning grey so
use an oil with UV protection and try to keep it covered.

I'm certainly no expert, but would gladly argue this point. Are you
saying wood turning "grey" is solely a UV issue?

In CA, redwood is almost universally used fer decks and fences. Using
it fer fences is a hoot, as the same ppl that can afford redwood fencing
are also usually the same ppl that have automatic lawn sprinklers.

Wanna see grey? Everywhere water hits a redwood fence, it turns
grey. It's a given! Water hits fence, fence is grey. You can take
it to the bank.

nb


Mostly UV. the wood I have out of direct sun is still OK even though it
gets wet. Are you saying the sun does not hit those fences? Argue away.

http://jackiehouse.com/outdoor-wood-turn-grey-time/
Just like you shedding dead skin cells, the dull grey patina that old
wood takes on is purely dead wood fibers brought about by UV rays coming
from the sun and yes, even sealed wood will over time, turn grey.
Considering that wood cannot regenerate fresh wood fibers on its own,
you have to slough off the dull grey color on your own.


https://blog.advantagelumber.com/201...ood-turn-grey/
Why Does Wood Turn Grey?

The natural weathering process of wood is a combination of chemical,
mechanical, biological and light-induced changes, all of which occur
simultaneously and affect each other. For instance, as air moves over
the surface of a wood deck, dust, pollen, dirt, and air pollutants
replace the exposed colored cells of the wood. This slow transformation
is also made possible through the exposure of the sun’s ultraviolet
rays, or salt particles in coastal areas. Depending on the species of
wood, these changes can occur anywhere between a few months to years.

http://www.a1-fence.com/why-cedar-tu...n-do-about-it/
Why does this happen? There are two culprits: water and sun.

Water erodes the outer layer of the wood cells that are still alive and
well in a plank of cedar. They are busy producing the natural oils which
gives cedar its nice color and smell.

Then the sun’s UV rays come in to dry out those oils. UV rays can also
fade the colors of just about anything over time. That’s why as I
evaluated the best stain brand for a cedar fence I spent a lot of time
looking at how well any given stain resisted the sun’s UV rays.