You are correct about the need to protect the cedar siding from a number of factors including fungal organisms and light damage. But the fact that you didn't have the shingles treated before installation is not critical.

With very few exceptions, all wood siding needs to be treated with a stain or paint. This includes: shingles, shakes, lap, drop siding, and even log homes. The wood needs to be protected from a number of of conditions. Your contractor may have been correct in assuming that the copper oxide from the roof may help reduce fungal growth on the siding, but failed to realize that ultraviolet light, wind, rain and airborne polutents will also damage raw wood and that the copper oxide will have little impact on those factors.

The copper oxide might even stain the wood in an uneven manner if it is allowed to run down the siding. But don't get me wrong, a properly installed copper roof should last for a very long time and my guess is that the impact from the acid rain is going to be of concern to the future generations that will own your house.

The idea of having the bundles of shakes or shingles dipped before installation is a bit of an oversimplification. In most cases, a simple dipping of this type would not have provided for an even application of the stain or wood preservative and the siding would still have had to be coated after installation.

I would urge you to have the siding stained or painted in the next year or two. The best method would employ a spraying and back brushing. This allows for the stain or paint to enter almost all of the cracks between the siding and for good distribution. This is a two person job: one on the spray gun the other with the brush.

I had this done on my newly shingled cabin in 1993. They used a linseed based transparent stain and applied two coats. I have been watching it ever since and it still looks great! However, my cabin is not exposed to a lot of wind and sun and I would expect that in most cases a transparent stain would have to be re-coated in about 5 years. Heavier bodyied stains and paints should last longer.

I hope this helps. Thank you for using our Express Service.

George

Thank You!

Hi George, I found my question and your answer. Thank you so much for the thorough and reassuring information you gave. What a relief to find out that I can still protect my cedar siding, and that the copper roof will last at least my lifetime. I'm going to give a page printed with your information to my painter, who said he could treat the siding next spring. I found your web site by searching the web for any site that included "red cedar shakes." There were dozens of sites and so it was by luck that I tried yours. I really appreciate the help and am very happy to know that there's such an expert source for me to go to with future renovation questions.

Thanks again, Meg