Wooden shingle siding discoloration

[William J. Decker]

Inspection a new construction house. Stone and wooden shingle siding with vertical wooden corner trim boards.

There were areas of discoloration on the siding and the ends of the shingles above the discoloration appeare to not have been sealed / painted. The contractor says that the siding was factory stained with a "transparent" stain (doesn't look transparent to me).

I believe that these shingles were just primed and should be painted once installed.

If you look above the discoloration (reddish) you will see a shingle edge that is not coated. Bleed?

Opinions welcome.

[Joseph Hagarty, CMI]

In need of painting / restaining.

[jbreazeale]

Agreed. Factory primed, needs painting. What is the name of the product?

[Marcel R. Cyr]

http://www.cedarbureau.org/installat...ual/page13.htm
It is possible that these Cedar Shingles might have been ordered from the Manufacturer with one coat of Transparent or Penetrating oil base product.

These finsishes will allow some of the cedar natural look to bleed through.
Most times a second coat will be applied after the install, but some people like the aging look.

I would reccomend a Professional Installer to determine whether the finish applied was an oil base or paint before reccommending painting or re-staining, in case the wrong product is applied by the potential client.

Marcel
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[InspectorRiggs]

Tannin (or Extractive) Bleeding: Redwood, Cedar and Douglas Fir are examples of wood species that contain naturally occurring, water soluble chemicals that tend to migrate to the surface with exposure to extracting agents such as water. After rain or heavy dew, coffee or tea-colored stains may appear on the wood surface. If the wood is coated, discoloration of the coating may occur when tannin extractives are dissolved into the coating solution by water, reach the surface and remain as dark, coffee-brown stains after the water evaporates. This reddish-brown bleeding is unsightly, but not damaging to the coating. It can be somewhat controlled using a good stain blocking primer before finishing. The shingles are referred to as "pre-primed" and do need a final finishing.