Don`t waste your time or money. The roof cannot be saved.

Due to the pulp being severly washed away, the grain splitting, and water soaking completely through (causeing the cupping/splitting), your efforts are only going to mask the problem. Cleaning will damage it further. (clorine is enviormently friendly)

There are Lifetime asphalt shingles on the market that simulate wood shakes well. These are Shangles and every granual is coated with copper, then the color is added on to that. No need for Nickle or Zinc strips. They hold up very well to coastal homes. (especially salt water).

That roof is very dangerous to walk on and too far gone to repair. If you want wood, it needs to be properly pre-treated before installation.

.......................OddBall

Thanks for the feedback, even though sobering.

Since a picture is worth 1,000 words, when do you think I need to replace the roof. We do not have any known water damage.

What do you think of Enviroshakes? www.enviroshake.com

Thanks.

Tad

The good thing about wood roofing is the tops of the shingle that go under the rows above them, stay in good shape longer than asphalt does. this, with the underlayment is what`s protecting you now. If your sheething is spaced (2/3 inches) , this time is shortened cuz there is no underlaymment. When putting a wood roof over plywood or non-spaced sheething, you must raise the shingles above the sheething with strapping or cedar breather (a mesh alot like brillo pads that comes in rolls like tar paper). Wood roofing is very good protection, asphalt roofing is waterproof and the roof sheds water, wood roofing absorbs water and the roofing is waterproof. They are expensive and require Copper metal works. You could easily get several more Seasons or a couple of years out of your roof now. (but it`s uuugggly )

The issues I have with Comp[osite roofing are, ....The heat from the home will melt snow and cause ice damming regularly, the wet bottom will cause the entire snow covered roof to avalanch without warnning....Composite roofing is light senitive, if your home shadows, the shadows will not lighten with time and on cloudy or clear days, you will see the differances.....The last is the hidden costs due to the products inability to be flexible/malable. You must use Copper metal in the vallies, eybrow windows, stepflashings, conicle roofs (turrets) ect. ect. making them hard to sell durring bidding. The average homeowner can afford the composite materials but not really the Copper works involved. I live in Boston and there are many many Victorian homes in the area, landlords don`t put up the monies to do the roofing correctly, they would rather go with the 35 year reliable shingles. Steel rusts and leaves staining, Aluminum reatcts with plastics, Copper is the only material you should use.

There are many many home that are ideal for this product cuz they lack the arcitectual design of Victorians. If they could create a composite that has the properties of asphalt, they would have a dimond ion the rut !!

Thanks for your feedback on composite roofing. You've clearly had a lot of experience.

I actually like our wooden roof a lot and am not terribly concerned about the aesthetics. We live on an Island. It's par for the course.

I am concerned about extending the life of our roof (now almost 20 years old). This is why I was asking about ways to remove the lichen without damaging the shingles.

On another site, a product called Shingle Shield was recommended by one homeowner, who had used it on an asphalt tile roof. The Cleaner is marketed by Chicago Metalic, the maker of a Zinc-based Roof Protector Strip, which is designed for use on asphalt roofs. Here is the website:

http://www.chicagometallic.com/product_frameset.asp?product=®ion=1&company=29&division=30&viewby=none&prodid=37&menuitem=52&rowcount=1

I spoke with the head of the Division, a very helpful guy, who was reassuring about its use on a wood shingle roof, despite the age of ours. This product, is sodium hydroxide-based and, therefore, needs to be handled with caution, even after it is diluted 10:1, as instructed. I'm actually more concerned about the effect it could have on painted surfaces and the side of our house, which does not need cleaning. If I decide to use it, I will not do it myself, but instead find someone who has sufficient experience.

Your welcome !!

From the photo I can see the rake for three rows, I can`t tell from the lichens how thick the butts of the shingles are. I can see that each row goes under the one above it and four inches under the third. I`m guessing 6 inch exposed, 6 inches under the one above it, 4 inches under the third. 16 inches is a R/R half inch butt. These would be sidewall shingles, not reccomended for roofing.

At the butt (the thickest part) it rests a little under half the length of the shingle below it, this is a little more, not much, than a quater inch thick. When the shingle is worn, water can soak all the way through this part, and be under the exposier. This will cause WARPING, CUPPING AND WEAKNESS.

My concern for damage to your roof is NOT the product to be used. It is the forces used to scrub, weight of the stageing and people traffic. That weak spot can snap easily. Then you need to repair those, potentially damageing others in that process.

The proper ROOF SHINGLE from wood roofing has a ONE INCH BUTT, and allows for 8 inch exposier, 8 inches under, and 4 under the third. (max. exposier) (min.Five) These are 20 inches high and tapper down to one eighth, not zero like sidewall shingles. You have a half inch under each butt.

Again, I can`t tell from the photo, but sidewall shingles will always, always, always, give you problems. They`re NOT ment for roofing.

All wood roofing shingles have either three quarter butts (5") or one inch butts (8") Never use sidewall shingles (Halfinch)

Be careful to make sure scrubbing and traffic/weight is kept to a minimum, and good luck !!

A picture is worth 1,000 words.

You are undoubtedly right. The shingles on the roof are white cedar sidewall shingles, not red cedar. The house was built by the previous owner. We bought it in 1995. He is likely to have cut corners.

Thanks for reinforcing the importance of our paying a lot of attention to how well the roof is holding up.

Tad