On composition shingle roofs… when there is no ridge vent do you note that the addition of one would improve heat dispersal from the attic area which increases the life of the shingles? Especially if there is curling present. Or just report the condition and leave any recommendations for further evaluation by roofing contractor?
Report the condition. Let the evaluator make (and be accountable for) his recommendation.
I report if ventilation is adequate. If not, I recommend that they consult with a licensed contractor who should perform calculations to determine if proper ventilation is present. Curling shingles sounds like reason enough to refer the situation to a roofer.
Just because ridge vents are absent, adding them may not necessarily be beneficial or cost effective. (For example, if there are 2 gable vents and mechanical ventilation, then that alone should be satisfactory.)
Thanks. Every so often I get the urge to recommend something that I’m not qualified to do. Appreciate the sanity of your opinions.
Here’s what I say when I see only gable vents. Typically, I may list options for correcting a situation, but leave it up to a licensed contractor.
“The attic space is considered to have inadequate ventilation. Only two gable vents provide ventilation for the structure. For venting to be effective the air has to be able to move. It is recommended that the structure be ventilated with both: A) An intake preferably located as close to the eaves as possible. (Most often this is done through soffit vents. Ensure the soffit vents are not obstructed by insulation.) B) An exhaust preferably located as close to the ridge as possible. “The total net free ventilating area should not be less than 1 to 150 of the area of the space ventilated except that the total area is permitted to be reduced to 1 to 300…” provided mechanical ventilators are used. When only gable vents are used, effectiveness is more determined by wind movement. Area calculations were not conducted; it is recommended that a state licensed general contractor evaluate the adequacy of attic ventilation and add ventilation as deemed necessary.”
Chris, were there standard roof vents? The soffits may be partially blocked by insulation which I like to see held back with baffles. There is also the possibilty the roof vents themselves may be partially clogged.
Hey Erol,
Soffit vents only. I’ll be leaving the reasons for shingle curling to qualified and licensed roofing contractors. I’d like to comment regarding the possible reasons “why” but it would only be an educated guess and that dog won’t hunt. Liability issues preclude it.
If it’s soffit vents only, I’d definitely say something about inadequate ventilation and refer that aspect of it to a licensed GC (see my language above). I’d separately refer the curling shingles to a roofer.
There is more to attic ventilation than what you can learn in a few posts, I have seen alot of good info in this thread, the best thing to do is learn what to look for, recognise the potential for inadequate ventilation, note it and defer/refer it to a qualified contractor.
Learn more at www.airvent.com, 3 simple courses to download and study, print them and keep them for a reference. Ventilation is a special animal, I have seen different preferrences used in different areas of the country but far too often I have seen them all falling short of compliance. I would not hestiate to say, expect more homes to be ventilated wrong than right. This opinion is based on my experience correcting the attic ventilation in homes.