Will moss cause my roof to leak?
Large amounts of moss can cause water to back up the roof enough to run over the top of the shingles. The buildup should be removed. Moss does retain soil and moisture that could harm the wood over time.

My cedar shake roof is surrounded by fir trees and needles accumulate in the spaces between my shakes. Should I have these cleaned out periodically?
Yes, it is a good idea to have a professional clean the debris off your roof. Cedar needs to breathe, and any accumulation of needles, branches, leaves and dirt will affect its lifespan.

What can I do to prevent moss buildup on my cedar roof?
A zinc or copper napthanate, in solution form, works to preserve your cedar roof and to retard future surface growth..

Do I need to power wash my cedar roof?
Power washing, done correctly, is one of the options available in the care and maintenance process. When done incorrectly, power washing can seriously damage a cedar roof.

Should I seal my cedar roof to keep out moisture?
No. Never seal your cedar roof. Sealing the roof will lock in moisture that would otherwise naturally evaporate during normal weather conditions. Cedar needs to breathe and thus a water repellant type product, rather than a water proofer is the best route to follow.

Can I use paraffin oil on my roof?
Yes, if it is a component of a proper cedar roof maintenance product.  Paraffin is sometimes used as a carrier for active ingredients and will usually weather away within six months.

I have a cedar roof on my home and it was recommended I have the shakes oiled. Is this a good idea?
In humid areas oiling shakes does not allow them to breathe and they cannot dry out properly which could shorten their life span. The CSSB (cedar shakes & shingle bureau) recommends you try a good fungicide/preservative. Keep in mind that no by-products, such as motor oil, should be used on cedar roofs. Hot, dry climates tend to accept oils better than moist/humid climates, simply due to the fact that oils can seal unwanted moisture into the roof.


Is it OK to nail down portions of shakes which have curled or bowed for them to lie flat again?
The CSSB (cedar shakes & shingle bureau) recommends replacing the shakes if they are curled very badly.

We are having problems with our shakes cracking and falling off. What do we do?
This could be caused by the nails or the nailing technique used at installation.

Should my contractor be walking on my roof using cleated boots/shoes? Will the tiny holes compromise the longevity of our shakes?
Small indentations made by cleats usually rebound over time.

My roof was leaking and a relatively inexperienced contractor came out and sealed up large areas with a few tubes of caulk. Is this normal?
No. Caulk is used to seal small areas, not substitute for proper repairs. Caulk will not stick to unfinished wood; it is only a temporary fix for cedar. Caulking is used successfully on finished wood and on metal flashing.

Is it ok for me to walk on my shake roof to examine it as it ages?
The CSSB (cedar shake& shingle bureau) does not advise homeowners to walk on their roofs themselves; if a roof survey is needed, ensure that you hire a professional contractor to do this work for you as s/he has the proper safety equipment, training, and procedures to perform this work safely.

We have preservative treated shakes on our 10 year old roof and some of them are starting to split. Is there anything we can spray on them to help them last longer?
Some splitting of the shakes over time is normal. If the roof is not leaking then the splits are not doing any damage and should be left alone. A professional can insert metal shims under any wide splits if you consider it to be necessary.

What can I do to prevent the shakes on my roof from turning gray?
There are many topical treatments available that contain color tints. If you have a pressure-impregnated treated product, always check with the treatment company to obtain their recommendation on roof maintenance prior to authorizing your contractor to begin work.


How can I remove paint from cedar shakes without damage?
The CSSB (cedar shake& shingle bureau) would suggest speaking to a local specialist regarding this matter. Each project has its own unique characteristics and challenges, so caution and expert advice is necessary.

What paint/stain/coating/finish should I use on my roof/sidewall?
For specific questions on paints, stains and coatings the CSSB (cedar shake& shingle bureau) recommends contacting your local, professional contractor or paint store.

Is staining a problem for painted shingles applied with electro galvanized nails?
The electro galvanized nails can get moisture through the shingle. Not only might they rust, but the paint on the nail head will come off and the rust will bleed through any cracks in the paint.