We have gable vents that face the prevailing winds on our ballooon constructed expanded cape. We have installed fire stops everywhere. We just had a new roof put on and installed ridge vents on boths roofs to make it look equal (one needed it).
The problem is: When we have a strong storm, water will come down through the 2nd floor windows just below the vents. I suspect it’s blowing in through the vent and finding it’s way down.
Question’s are: 1) Is it normal for this to happen sometimes and can it cause damage? 2) Should we have both types of vents on the same part? 3) If we can (I like the added ventilation) is there anything we can do to help stop the water? 4) should I just go up there and tack a piece of sheet metal over the vent from the inside and let the ridge vent do it all?
Replies
Maybe this will help. I'll try to post a picture.
I would think that as long as the soffits are vented, the gable vents are redundant and could be blocked off. If the soffits are... the attic air heats, rises and leaves through the ridge vent, that draws air in through the soffits to run along the underside of the sheathing...and the cycle continues. If the gables are left open, air would move back and forth through them and diminish the convection current.
'course I could be out of my mind too, there's others here with more experience than I!!
Mike
Oops.... forgot the part about the soffit vents. There aren't any yet! We never have had a problem with ice, but because we put plywood over the old loosely space boards when we re-roofed, we made sure there was room for air to move from them should we install some later. Proper vents were installed years ago when the rooms were renovated. I understand what you mean about convection. Maybe for best ventilation, I should put the vents in and seal off the gable vents. I had heard once that you shouldn't have both ridge and gable vents... true?
Maybe a evaperator pan as Dinosaur mentions will work and leave things as they are?
Yesterday I couldn't even spell plumber, today I are one.
Dinosaur may well be right about the ridge vent, but I can't see 3'-6' hanging out on a roof with that much pitch. You might be a better judge of whether the winter snows accumualte that much up there, and whether the ridge vent cleans itself all winter or not. If snow accumualtion isn't an issue, I'd vent the soffits and close the gables. Collection pan + fan or drain seems like a band-aid, but may be more common than I'm aware.
Mike
Edit: As far as having ridge and gable vents goes, you still have an air inlet and outlet as long as there are no snow blockage issues, but you don't have flow over all of the roof sheathing w/out soffit/ridge vent combination. Ideally, you'd want the inlet size/outlet size to be about 1 to 1. Airflow values should be available in terms of flow per sf for all. Sooo, if your ridge vent is way too small compared to the soffit vents, you may want to supplement with a gable vent.
Edited 6/8/2003 2:24:19 PM ET by Mike Gabriel
From the sunlight on the house in your picture, the gable wall that shows is either facing west or north (unless you took the pic first thing in the morning, which it doesn't look like). And you're in Vermont. This means that gable vent is facing pretty much into the prevailing northwesterlies. Question: do you get water in through the opposing gable vent (the one on the other side of the house) as well? Second question: during what type of storm does this usually occur? Large, relatively stable lows that move in from the NW with winds that neither veer nor back; or short, violent line squalls (summer thunderstorms, but nasty ones) that come in from all different directions with winds that shift quickly as the storm blasts past your location?
Another question: You say the water 'comes in through the 2nd storey windows'. Do you mean it drips down over the sill, or weeps down the case from above?
Finding the appropriate solution to your problem depends a lot on the answers to these questions.
In general, I don't approve of ridge vents in high snow regions, and Vermont can pretty much consider itself such a zone. What happens to a ridge-vented system when there's three to six feet of snow pack on top of the roof is that any warm air leaving the ridge vent at first melts a channel into the snow pack from underneath, and then, as the channel gets big enough, the surface of it ices over, so you've got a sort of ice tunnel there surrounding your ridge vent. Now the air trying to permeate the snow pack can't do so, because it's hitting a wall of ice, so it just curls around inside what is essentially a sealed pocket. The air entering at the soffits has no exit, so active ventilation stops.
I'd suggest as a test measure stapling a polyethylene 'bib' to the framing under the vent, and leading it into a large drip pan on the floor of the attic. If your problem goes away, this will tell you that the water is coming in there. You can then decide if you want to (a) close off that vent; (b) install some sort of permanent water catchment and evacuation system; or (c) try to reduce the vent's vulnerability to high wind.
If the problem persists, then you'll have to look elsewhere for the culprit.
Good luck.
Dinosaur
'Y-a-tu de la justice dans ce maudit monde?
Thanks for the reply. I forgot that we don't have soffit vents yet. The water comes down through the top of the window casing only on really violent storms. The gable vents face north and south. Picture was taken from the southeast. Thanks to Global Warming (although I didn't hear it mentioned much last winter) we don't get much snow here anymore. Please read my reply to Mike Gabriel below.
Oops.... forgot the part about the soffit vents. There aren't any yet! We never have had a problem with ice, but because we put plywood over the old loosely space boards when we re-roofed, we made sure there was room for air to move from them should we install some later. Proper vents were installed years ago when the rooms were renovated. I understand what you mean about convection. Maybe for best ventilation, I should put the vents in and seal off the gable vents. I had heard once that you shouldn't have both ridge and gable vents... true?
Maybe a evaperator pan as Dinosaur mentions will work and leave things as they are?
Yesterday I couldn't even spell plumber, today I are one.
Check the head flashing on the window. The vent might not be the culprit at all.
Dinosaur
'Y-a-tu de la justice dans ce maudit monde?
Just so happens the wife had me washing the outside of windows today. So, while I have the ladder up there I checked. Flashing looks good.
I know this isn't the cause of the problem, but what about the fact that I have dual vents? When/if I put soffit vents in, should I block off the gable vents?
As I said in my first, long post, try a skirt and drip pan to see what that gives you. If you no longer have the water coming in the top of the window casing, that'll indicate pretty strongly that the water was coming in the vent. After that's been determined, then you can decide which of the three options (or any others you may get in other people's posts) will best suit your situation. No point in doing anything major until you're sure of the cause of the problem.
As far as the 'dual vents' questions goes, I still don't consider ridge vents 'real' vents in snow areas, even with global warming. If you're worried about those big gable vents you've got now messing up convection flow or whatever, you could replace them with much smaller (12-18") hexagonal or round vents stuck as close to the peak of the gable wall as you can.
Dinosaur
'Y-a-tu de la justice dans ce maudit monde?
Edited 6/7/2003 10:52:39 PM ET by Dinosaur
Before you assume the vents and/or the windows leak,trying do the age old experiment with the trusty garden hose. It will usually rule out on or the other. Could be a leak in the roof also. Out here is SoCal(It doesn't rain much) there seems to be a problem with roofers, siding contractors, and/or whoever flashes the window, doing their work properly. Losts of lawsuits concerning water leakage/damage. Saw a track of homes where ALL the roofs were being torn off. None were done right and some even had the roof paper installed from the top of the ridge first and then then applied going down to the facia. Opposite of the correct way to lay it.
next time you go by a large commercial building, look at their street level air vents.
many of the "slats"are at a steep angle, and have a lip at the upper edge of each "slat" to stop water if it is driven in and up by the wind. i had a problem like that and redid my vents.
also some commercial alumnum vents I have seen for sale in lowes for use w vinyl siding have a seam on each side on the bottom that unless caulked, will really pour in the water. very dumb design - easy to make leakproof by the manufacturer but no, you get an alu vent that the inside seam on the unit must be caulked (between the vent frame and its own slats, not between the vent and the house!!!!!!
i asked the lowes manager why do you sell this junk?