It is dangerous to walk on any roof. If the roof is wet you might slip and fall. And it is possible to do damage to the roof, by cracking shakes or even breaking them if they are not #1 shakes or shingles. However, a professional roofer knows how to walk, and will mark and repair any problems that arises. The alternative to walking on the roof is to leave it to nature. This works well in composting, and it works well in letting your roof rot. We advise the intelligent middle road. Allow a professional to inspect the roof and replace rotten or damaged shakes, then protect it from the ravages of nature.

Powerwashing removes important resins from the wood and does other damage as the work is done. However, the Cedar Bureau has standards on this procedure, and they should be followed if this method is used. We would recommend using a Cedar Bureau member company. However, it is hard to get good economic value from this unless you are selling soon. Beware of exaggerated claims.

In the Lower Mainland of BC, we have ideal conditions for algae, mildew, spores, microbes, moss and lichen. The smaller life forms lie on the surface of the wood and live on the moisture from the atmosphere and the nutrients in the wood. They chew up the top layer or two of cells on the wood, which then turn dark in colour, and very slippery in the wet weather.

New shakes do not have this problem. It takes a year or two for weather to break down the resistance of the resin in the new wood Then microbes do their destructive work. That's when it will blend. But doesn't it make more sense to treat all the shakes so the life stops destroying them? When ROT Ban works for a few months, the pulverized surface cells of wood wash off, leaving a clean, whole wood cell surface. Then the wood stays that way - about the colour and texture of driftwood.

ROT Ban sticks tenaciously to the wood cells, and re-activates each time it rains. We know from experience that it keeps doing this for at least four years.

Farmers and settlers would often split their own shakes from the trees nearby. These were old trees, with lots of resin. The cuts were often good and thick. Then they installed the shakes without tarpaper, to allow lots of air to circulate through the shakes on the roof. All these things were very good - ideal.

Our wood today is comparatively young when harvested. There is less resin, and more knots. Resin is the natural preservative in the wood. Knots disturb the ideal "edge grain" exposed surface of the shake. Wood today is graded, with #1 being edge grain. However, some #2's are allowed in a bundle, and it is up to the roofer to cull the #2's for a premium roof. There are various cuts of shakes or shingles, each with its own advantages, and some don't weather as well as others.

The building code in the Lower Mainland of British Columbia requires the use of tarpaper, to keep windblown water from entering. This is a disadvantage for longevity, because it reduces the circulation of air.

Then there is the roofer, who should be a craftsman, and if this person cuts corners, it adds problems. Acid rain and a wet, warm climate aggravate the problems. All told, as you can see, there are a lot of reasons to have a professional check and maintain your roof to get the best value.

Our inspection will tell you, or you can pick up brochures on the products and compare what you have with what the specs on the brochures say. Observe from a window, or ladder.

For free brochures and shake descriptions, email us.

We have been in business since 1960. We have a track record in the community and with the Better Business Bureau - check us out! In addition to that, We will show you the clearest proofs available to verify our inspections.

Once the wood has weathered for a year or two, it can be treated. You will get the best economic advantages by treating it early in its life. Up to year 10 gives you the maximum value. However, it can be applied with great benefit anytime before rot gets a firm grip.

If the inspection shows rot is consistently growing deeper than 1/4 inch on some part of many of the shakes all around the roof, it's too late to do much. Typically this will be about year 18.

Since simple plant life forms are the main culprit in deterioration, their reduction is the logical approach to preservation. Zinc strips work when rain rolls over the metal in the strip, and the metal particles are carried down the roof. The environment created keeps the plant life at bay.

This set of photos dramatically shows the results of different growing conditions on a small piece of roof.

This section of roof is just below a chimney of wood siding. The interface of shakes to wood includes the use of metal flashing. Interestingly, the metal flashing gets various amount of rain running over it, depending on the amount of exposure of metal. Most areas have about 3" of metal for water to run over, but the area at the side gas about 8X that much. There are other factors here, including the fact that this spot is lined up to get a high amount of shade, but the differences in simple plant life growing here are mainly due to the amount of metal "contamination" in the water, which is then bathing the roof.

Note the streaks of different mildew and moss types, running down to the gutter.

Note the way the streaks are wider at the top and narrower at the bottom.

Note that one streak is limited to a certain strain of blue-green algae, and the inner streak is clean of all simple plant life.

The clean area is being effectively preserved. Unfortunately the area is limited and various, due to the loss and dilution of the metal particles as the water travels down.

Zinc strips work this same way, except that it is more consistent. The strip gives an even 3" area wherever it is installed. Zinc is more effective than powder coated metal used in flashings.

However, there are weaknesses in the zinc strip approach. It, too, loses effectiveness about 15 feet down the course.

So if it is to do a good preservation job, it should be applied every 15 feet, and under each hip, or angular cap.

The result of this pattern is not eye pleasing, and expensive in zinc.

Zinc strips also have the disadvantage of curling over time, along with warping and breaking free of nails. It lasts about 5 years before oxidizing and loosing its power, and needs to be cleaned well or replaced. Before that time, also, the warps and curls are creating uneven flow, as water runs along the strip to find the lower points. The uneven flow of metal saturated water creates uneven effectiveness.

This is why the use of zinc strip has limited value. On the other hand, ROTban is applied in such a way as to bond into the cells of the roofing material, and stay bonded, activating with each rainfall and working on the spot and for a distance below the spot. The result is continuous, completely even performance throughout the roof field, and thus a beautiful appearance.