Hello, There are a lot of factors that come into play with how red or white cedar will weather, the underlayment, the finish on the shingles etc. There are products/finishes that will cause the shingles to wear to nice grey tone(for white cedar) and provide a more even weathered look. In general going with pre-dipped cedar -white or red, with either a weathering stain or bleaching oil should produce results without black streaks. Just be weary -Cabot was having issue with their Oil based bleaching oil causing mold to grow on the shingles, the water based does not have that problem. Speak to your builder for recommendations on brands that have worked well for them. Typically getting the shingle pre dipped from the manufacturer will provide the best quality finish. Maibec or SBC brands are two common brands and you can visit their websites for finish colors and details. The above home is also in a 4 season climate (Coastal Massachusetts).

Your answer was terrific. Had precisely the same concerns for a new Gulf Coast home.........