Roof damage quiz

[Brian A. MacNeish]

Originally Posted by hmcclard

That actually looks like Lichen. And, yes. Zinc stops it. Check hardware store for zinc strips... comes in a package of maybe 40 feet worth of 3 foot strips for something like $75; the strips are about 3 inches wide and get nailed just after the ridge vent. Rain hits them and the zinc ions kill the lichen or moss or whatever it is, roof stays clean. And, the spots on the shingles look like where lichen was growing and died got washed off.

I would bet on moss......began an introductory taxonomy course on mosses and lichens in 1975......think I can remember much from it??

[Kenton H. Shepard, CMI]

That's delamination.
The asphalt layer containing the granules has delaminated from the underlying asphalt. This is more likely to happen with poor quality asphalt and may have been made worse by moss holding moisture against the roof. The area beneath the tree will be shaded and stay damp longer.
Moss typically comes off fairly easily and its removal won't damage good quality shingles in decent condition.

If falling acorns can cause damage that extreme, the entire roof is toast. Unless you actually saw an acorn hit and cause identical damage... it's hard for me to believe that those are impact-caused. An impact would press granules into the asphalt, not cause delamination.

Impact causes a fracture of the mat which starts on the underside of the shingle and propagates toward the surface. It doesn't matter whether the impact is a hailstone or a gigantic lead-filled acorn.

This type of damage is most common with organic shingles because they consist of outer asphalt layers bonded to a mat core saturated with asphalt of a different viscosity.

If the property has large overhanging limbs, it's a good idea to recommend evaluation by a qualified arborist instead of recommending that the tree be taken down. It takes a long time to grow a big oak tree and they can add value to the property.

[ROBERT V. YOUNG]

OK I am ready to give it a go.
1: I do not see gable vent thats 1.
2: :See ridge vent and it will not function well with out secondary venting in place.I can not see soft venting from pics but.I do not like ridge venting myself.(personal taste)
3: Moss on roof is telling signs of poor roof health and improper sun exposer and venting.
4: Those bare spots on shingles are from moss that had been swept clean.I think they did not go farther because they saw damage from the area they cleaned.Area not cleaned is large so Imagen the bare area it wold leave..
5: I see a plumbing flange thats old but a new boot at the bottom that leads me to think a roofer was up doing maintenance.Per sales maintenance on the cheap.Boot looks like an electrical boot for low slope angles.
Sorry but thats what the pics tell me.

[David Garton]

Originally Posted by hmcclard

That actually looks like Lichen. And, yes. Zinc stops it. Check hardware store for zinc strips... comes in a package of maybe 40 feet worth of 3 foot strips for something like $75; the strips are about 3 inches wide and get nailed just after the ridge vent. Rain hits them and the zinc ions kill the lichen or moss or whatever it is, roof stays clean. And, the spots on the shingles look like where lichen was growing and died got washed off.

Or try this site
http://www.zincshield.com/home.html

[ROBERT V. YOUNG]

The ridge vent was put in after and not long ago. 2 Vent-mar 60300
Attic ventilator for sloped roof is what I would have installed.
Slope to low for me to use a ridge venting as air exchanger. It is cheep ridge vent and to low and not profiled properly. It should stand prouder and have shingle cap at least, to provide protection. From what I see ,looks like rain might be able to inter from the sides on a windy day,
As for my statement about the plumbing stack.
Everything is right except my statement about it being new.
It has rust stains and I see 2 types of galvanized metal being used together and rust might be from Galvanic corrosion reaction.
Paint peeling because it was not treated right before painting. There is a wax substance on new galvanize and it must be taken off before you can apply paint.
The shingles look old and the newer ones do not line up because they are different size due to (I guess metric) verses standard being the older ones.
See how they did come close to being offset properly, but as they extended the horizontal course the rain notch almost over-laps each other.
Any way that's what I see and happy I gave it a second look.
I have looked at lichen's and have found pictures that come close and yes it should be asked as a question.
I am going with moss for I have seen this many many times on flat (built up roofing) to shingles and its because of shading and old, old roof.
I hazard an age of plus 20 years on this one in the photos.
I have seen shingle roofs older than 35 to 40 years old rain notch worn out as to expose decking and still no leaks due to the slope.

[Kenton H. Shepard, CMI]

If there's enough moisture to grow moss and lichen, and the damage was caused by lichen, then some lichen should still be visible on slopes that have moss visible. I think it's a bad batch of shingles.

[ROBERT V. YOUNG]

Kenton.
I am with you on bad batch, inferior process, low quality control standards with product line. Wow thank god the industry in Quebec is kept up to date on quality control. use to be lots of problems in the early 1980,s and 1 manufacture went to next province to avoid being put under such scrutinize of there product.
Makes me wonder who good there product is today. They are still around.