I recommend www.cor-a-vent.com to most of my clients. They manufacture a vent for every roof field you can come up with.
I’m impressed with this one, made for those smaller/lower overhang roofs.
Your “facts” are a personal opinion. How do you know for sure that every call you make about premature failure is a venting problem and not product problems.
FYI:
I ran an insulation/roofing/siding, etc company in a small town of 5,000+ for 10 years. We filled many cathedral type roof cavities on 1.5/2.5 storey homes with blown cellulose as with those steep cavities it is impossible to leave an air space when blowing. The best thing is to blow at a higher density to prevent settling.* I had NO clients that came back to me saying their roofing was failing due to my filling the cavities…and in a small town, if this was happening, my competitors would be having a field day running down my practices especially if they caused failure!
*(and higher density cellulose reduces warm air leakage from the house substantially-An architect’s house I recently consulted on had a blower door tested air leakage reduction of slightly under 50% when blown with cellulose.)
Because when the roof shingles fail early, there are no vents installed.
Pretty black and white, plain and simple isn’t it?? You did not answer my question from above:
"We had a case on these boards with lots of ventilation and severe failure after 10-11 years…explanation??"
Have you had a look at the class action suits with Certainteed?? I just came up with 11,000 hits. Do some reasearch!!
http://classactiondefense.jmbm.com/2007/03/certainteed_class_action_defen.html
“Eight class action lawsuits were filed against CertainTeed Corp. and other defendants advancing negligence and products liability based on alleged defects in roofing shingles manufactured, warranted, and distributed by CertainTeed”
SO? Firestone had a tire failure, and were sued, does that mean all tires are defective? When you see failing shingles, do you automatically report defective materials?
You’re referring to your area, not mine. I have never once found a failed roof with plenty of ventilation, unless the vents themselves are blocked with insulation or not cut in on the underside.
Defective shingles (from the manufacturer) is a whole different topic. We are on the subject of improper ventilation, not defective shingles.
Most of the time up here, its an age problem. But some 15 year warranty shingles manufacturered in mid 90’s are failing at 11-12-13 years. Or like the 25 year warranty roof mentioned earlier- early signs of failure-curling & cracking- at 8-9 years.
My shingles are BLACK, 10 year warranty, installed in 1987… about to start their 22nd year. I might replace them this year if I have time but they could last 2-3 more if I wanted to stretch it. Had 2 events with hurricane strength winds in the last 5 years…never lost a shingle tab. When I mentioned replacing them this year, my wife (father was a lifetime carpenter) said “Why? They still look pretty good”. That’s the difference in shingle quality between the pre-90 period and recent years.
Don’t you think with oil at $143 per barrel that they might try to reduce the amount of, or replace, oil products with other fillers in their shingles to be competitive?? NO!! NO!! Never!! The manufacturer’s are always honest and truthful!!
How do you tell whether shingle failure is from improper ventilation or defective shingles? Just by looking at venting? Could be shortchanging your customers when you call the venting issue if the shingle failure actually is from a defective design!!! They will just assume the roofer is at fault and not the product, losing out on any awards/warranty/offers of replacement/compensation from the manufacturer. The venting issue is not so cut and dried!!
From the US Dept of Energy: http://eber.ed.ornl.gov/DOEceilingsattics_771.pdf
In the second paragraph, they now say, firstly: *" make sure: *Ceiling is properly sealed." This reduces the need for attic ventilation as much less moist house air is escaping to the attic where it condenses on cool boards/framing. The existing small vents usually are now enough to take care of the reduced moisture load on the attic!!
**A T T I C V E N T I L A T I O N
**
"Most building codes require roof vents to expel
moisture that could cause insulation or other
building materials to deteriorate during winter.
In summer, ventilation* may** reduce roof temperatures,*
thus lengthening a roof’s life.
However, researchers are investigating whether
attic ventilation is beneficial for all climates. For
years, researchers have believed the cooling
benefits of ventilating a well-insulated attic are
negligible. Some experts also question whether
ventilation effectively removes moisture. Until
the research results are available and accepted,
builders should follow local code requirements,
which usually dictate attic ventilation."
So some of the research must be pointing in other directions or this wouldn’t even be in print!!
You should also talk to larger roofers about how many claims are being settled where the client has to keep quiet in order to receive the compensation. This is data that doesn’t get into the public domain!!
I’m done…C YA.
Could it be possible that both can be an issue?
Absolutely. But some people have a hard time trying to comprehend that.
I know.
Slightly… 6/30/08 5:38 PM Brian, You do not have to be a scumbag jackazz everyday! Take today off!
To the unsigned (who is obviously missing important round parts):
With increased energy efficiency, sustainability and green building practices being the new paradigm*, either truly understand it or be lost in the ozone. Change is happening quickly and with the numbers of building failures from mould, rot, siding failure, stucco failure, it’s obviously only a few actually understand the whole picture from a building science perpspective and apply better practices (like rainscreens) in response.
- Read *“The Structure of Scientific Revolutions” *by Thomas Kuhn. It’s where the term “paradigm change” became popularized. Took it in Philosophy of Science class in 1971
Slightly… 6/30/08 10:06 PM Valley…and moreso, Lott are NEVER wrong
I’m touched!