Ridge vents are normally installed with the downslope of the top shingle
covers in the same direction as storm wind. Unfortunately, ours were
installed backwards. As a result, a strong rain in a storm wind would
shoot rain up the bottom of the ridge vent shingle. How serious a
problem is this?
Short of taking it all out and starting over from scratch, is there anything
that can be done to address the ridge vent facing into storm wind 180
opposite of what it should be?
I am not quite sure what you mean. The downslope of the top shingle
covers? I can't follow that. The shingles covering a ridge vent are
centered over the ridge vent and the openings are on both sides, so
from either direction the ridge is pulling air. The design of the
ridge vent itself is what prevents water from getting through to the
inside. If that doesn't address what you mean, please rephrase what
you're trying to say.
Our ridge vent is a plastic piece with vents on either side of the roof.
On top of each ridge vent, there is a shingle cover/cap. The shingle
cover/cap matches the other tiles on the roof, and it provides some
protection to the plastic ridge vent.
Observe this photo:
View the length of the ridge vent from the side. The shingle covers
overlap each other like this:
\ \ \ \ \ \ \ \ \ \ \ <<< storm wind moves any rain left
direction over shingle covers
The idea is to have the exposed edges of the shingle cover face away from
the direction of storm wind. Presumably if you reverse the shingle cover
orientation, then rain blows up into the overlapping edge of each shingle
They installed our shingle covers so that the prevailing storm wind is
opposite from the above diagram (e.g., storm wind comes from the right). I
am just asking does this represent a serious risk for water intrusion into
Do you currently have a water/moisture problem there? You say 'serious
risk' which implies you are worried but don't have a problem. If you
want things to worry about, there are many, many other things that are
No. What it represents is that you have issues with your ridge vent
for some unknown reasons. From your posts it appears from the cheap
seats that you don't really understand how they work and what
constitutes a problem. You have suggested modifications to a ridge
vent that would very possibly cause greater problems than what you are
imagining is happening.
So what's the deal? Are you pissed off at the roofer or something?
Have you had bad experiences with ridge vents? Maybe you heard a
story about problems, I don't know, but you're tilting at windmills on
this one. Stop worrying and pick a real battle where your efforts
will have a beneficial effect.
We live in a very low humidity environment. The home had no ridge vent for
over 30 years and in that time never once had any problem with humidity or
water collecting in the attic. That is why I am sure that if the ridge
vent could be closed that it would not cause humidity damage. Since there
is no easy way to close off a ridge vent, I was no longer pursuing that
thread of conversation.
I am not having "issues" with the ridge vent. I am simply asking if the
orientation of the shingle caps into the rain would allow rain to pass
through. If answer is no fine.
The roofer who installed the ridge vents in the wrong orientation is the one
who pointed out to me that the problem existed. I am simply checking is
that something I should be worried about.
No, you don't have anything to worry about. There. Is. Nothing.
To. Worry. About.
I really have absolutely no idea what the roofer is talking about as
far as the cap shingle orientation, and it certainly isn't a problem.
Wind blows in all directions. Much stronger winds than usual can come
from odd angles. Wind swirls around due to the turbulence at the peak
of a roof. The idea that you can pick one direction to lay the cap
shingles, and that will prevent water entering under all conditions is
simply absurd. A roof needs to be watertight no matter the direction
the wind blows.
In a 'freestanding' ridge, with both ends terminating in open air, cap
shingle laying starts at both ends and progresses towards the center.
Where the two opposing runs meet, and where the final cap shingle
lands, is a matter of aesthetics and nothing more. If you want to be
a prick about it, or if you feel the roofer knows he did something
else wrong and is picking an odd way of breaking it to you gently,
then have him go back and 'fix' what he thinks he did wrong.
As Rico has pointed out, the direction the cap shingles face is just a
best guess to cover the most common wind direction.
Furthermore, all the ridge vents I have installed form a complete cover
over the ridge, the shingles are just there to look good. They would not
leak if there were no shingles.
Now, that said, I don't think your cap shingles are installed correctly
anyway. Not because of the direction they face, but because they do not
have the proper overlap. There should always be at least two layers of
shingles at any point. Your roofer cheaped out, and spaced the shingles
way too far apart, so there is only single coverage with minimum
overlap. We set them with a 5" exposure, your roofer has about 8" or 9".
*That* is why they may let rain through.
He also skipped the step where you cut the tails at a slight angle to
present a neat appearance
The photo I put up was a manufacturer's product display photo of a random
ridge vent product. It's kind of scary if the manufacturer did not install
his own product correctly.
The actual roof uses a GAF ELK Ridglass style "Weathered Wood" and Item
#0871900FR. This ridge cap shingle is a pre-made kit.
You initially said that the roof cap shingle is decorative only. But the
next paragraph says that you need to always have two layers of shingles at
any point. What is the function of minimizing the overlap? Is that to
strengthen against wind exposure?
Do you think the 5" exposure guidance applies to the product above?
Note that the Ridglass instructions here seem to imply an 8 inch exposure:
You would still recommend 5 inch?
What would I recommend? I would recommend not installing those cap
shingles. They've elevated looks over water-tightness - a
particularly stupid idea in any roofing product. As I mentioned
earlier, prevailing winds does not equate to the _only_ wind
direction. Air is by definition a turbulent medium. If I had a gun
to my head and had to install those cap shingles, I would use roofing
cement over each nail head, additional dabs to adhere the caps to one
another, and charge the owner through the nose.
I still maintain that the leak potential is minimal in a standard cap
shingle installation that is done correctly, regardless of wind
direction, but the caps you are asking about is another matter and
only time will tell. If the roofer knew he put them on incorrectly
and told you about it, he's an odd bird. Some would have not told you
and hoped for the best, and others wouldn't have told you and just
replaced them on their own. The better roofers would have read the
instructions and either complied or talked you out of the those cap
The contractor in question has done a lot of work for me and has always been
extremely diligent and extremely honest, which is why I keep using him.
He may have chosen an inferior product here, and I guess at this point we
have to hope what he chose holds up to our moderate climate. Fortunately,
this is not a rainforest climate, but we do get the occasional good storm,
so any reinforcement I can do on the install now is probably time well
Which ridge vent products and cap shingles do you like to use?
I agree that you should hang on to good contractors you're comfortable
with, and I'm not thrilled with the cap shingle you've got that
requires a specific orientation to the wind, but it sounds like your
contractor didn't pick up on the installation direction requirement
until after the fact.
HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here.
All logos and trade names are the property of their respective owners.