Snow in roof vents?

My daughter has snow coming in her roof vents, to the point when the snow melts she has a wet ceiling. She has a low profile vent with screen inside over the opening. They had this problem a year ago and had the vents, insulation and sheet rock replace. Does anyone have a idea what vent will not allow this. It does not happen every time it snow, just with strong wind and snow. 40-60 mph wind.

A lot of vents in Canada and Alaska vent through the exterior wall and then rise a couple feet before turning downward again. No holes in the roof that way.
But in your daughter's case, I would install two 90 degree ELS on the top of the stack so that the opening faces downward.

Quick fix and worth a try

White17 ELS?

ELBOWS ))) 90 degree turns ))

Sorry. Lazy typing

EDIT ! I reread your original. I thought you were talking about plumbing vents.
Now I'm guessing you meant a vented ridge ??

My guess is ridge vent ….not plumbing pipe vents

It is roof vents. Not a ridge vent. About a foot square, two or three inches tall, flat on top.

Curious to hear some replies also. I have a ridge cap roof vent the full length my house. I end up with small snow drifts up in the attic when we have strong south winds. I think snow shoots straight up my roof and goes in the roof vent. I need something different too.

I am far from an expert but I would think a vented ridge cap and vented soffit would give enough ventilation and eliminate the problem.

A ridge vent may be a option for you depending on the layout of your roof. The turtle type attic vents that you have are notorious for some snow getting in I don't think I have ever tore off a roof where the insulation hasn't sagged a little under the vent.
It usually isnt a problem most of the time but if you are in a open high wind area I can see where enough snow could get in to do damage.
All ridge vents aren't the same either so keep that in mind

How big is small? Direction of wind and ridge could make a lot of difference I would think. That and the location of the house. She is NW Bismarck on top a hill with miles of open ground N NW.
They just change the vents to the ones the roofer said he never saw snow get in, and now one year later more snow. A ridge vent may be the answer.

Some of that snow is like dust here the kind that blows out of a vehicle’s defroster when the fan is turned on in the morning.

I have those type of vent also but never had a problem with wet celling. I have had them covered many times but seem to clear open.

Snow is blowing in through the screen on the vents. It builds up enough snow in the attic, that when it melts it soaks the insulation and sheet rock.

You need to get rid of those type of vents and switch out to gable vents or if you have a hip roof, ridge vents. I have gable vents. When we have blowing snow a little bit gets in. Almost like a dust as someone posted earlier. I cut a piece of 4x8x1/2” drywall and placed one under each gable vent. These catch the small amount of snow that does get in, where it melts and evaporates. Drywall is pretty water stained now after 30+ years. Have never had so much snow that it runs off into the insulation, much less dripping down onto the ceiling below.

Have a ridge vent in the pole barn and have never seen where snow gets in there, but haven’t really paid too much attention there. Maybe someone who has that type of vent can comment further.

They make either louvered covers for those vents or you can buy louvers to put in the opening . I've seen them but have no idea where they were advertised.
Maybe Google louvered roof vents and she if that is what she has now or not.
I know of this problem, ceilings can fall in over it.

If the opening in the top of the roof sheathing is cut too big, the extra airflow will "assist" the snow sucking in...that opening should be 1" MAX, for positive airflow, as you should have 2" MIN coming up from the bottom

I had trouble with the vents like that on my place. I glued frog skin? over them. Same stuff used on snowmobile cowling openings.

Osky

I agree with this. If you are getting wind-driven fine snow inside the attic then the turtle-type roof vents aren't going to work (as you have already discovered).

In your situation I think louvered gable vents would be best at preventing wind-driven snow from entering the attic. Continual ridge vent would be my second choice. As mentioned above, if the house has a hip roof gable vents are not an option.

Ridge venting works best at removing excess heat from an attic but only if there are vented soffits on the house and clear channels from soffit to vent. I don't know how much of a concern excessive heat in the attic is in North Dakota though.

Neither option will be cheap but both will be cheaper than repeatedly replacing insulation and sheetrock.

Probably a 3 inch high drift and 2 feet long. My house is a modular home so has a marriage wall. Drift sits right on top of the two center walls. When it warms up and melts you can here it dripping. Home sits angled northwest-southeast. I have a building about 30 yards away from my house. When we get a strong southwest spring wind, the wind comes around the shed and it's almost a vacuum effect blasting at my house. My roof line is wide open to that wind.

I am not sure louvers would be the answer with the wind we get. Any louvered vents I have been around here, when it is blowing are opening and closing from the wind full time. You can hear them. I wonder about covering the screen with something. Something like this. I take it that is what Osky is talking about.

If it is dripping it is too much. She only has only had a problem with it twice in ten years. So it takes a certain combination of wind and snow. Which I figure is the same for you Skogmann.

That looks like a roll of matrix used over a ridge vent and under ridge cap shingles.

Mark,
I have and prefer turbine vents, but you have the right idea with that roll pictured. They make roof vents already with that type material in it for just that reason. You may be able to convert her current vents.

Rally She has been talking to both the contractor that replace everything last time and the insurance company. Both of them she is friends with and they don't match what they say. Insurance guy says he put turbines on his house and ended up replacing them. He said the made so much noise they drove you nuts when it was storming. He also had one fly apart in a good wind. He said he would go up and spray them with dry lube and that would help a little while. The contractor says they are not the way to go. If a person could get turbines with sealed bearing, they may be a good answer. I think the Matrix as Lugnut calls it, is the answer. I do apricate all the replies.

I replace my turbines about every ten years. The nylon bearings wear out, and the ones with metal bearings do make noise after they get dry. I buy the same brand and just replace the tops, so don’t have to reseal and rarely re-level. Can’t hear mine at all unless next to them on the roof. Paint them to match roofing color.

how hard is it to get in the attic ?

my brother had a similar situation in his pole barn it had open eves and the wind would blow the snow in up the wall under the eve and it would pile up on the north wall inside


it would get 2 feet deep in there if there was a lot of wind from the north

if it isn't too hard you might be able to close them by nailing or screwing some 2x4 pieces to the rafters and make a piece of plywood to slide in with a 2x4 screwed to it as a stop that would really cut down on the drifting in the attic to just be able to close them

if it is not easy to get up there and slide them in around Dec 1 and take them out around April leaving the ones that aren't an issue out so you get some ventilation

true you want your attic the +-5 degrees of outside ambient when measured at midnight but that is a lot more of an issue in the summer with the prairie heat

you wouldn't harm your roof any to have anything below 30 in your attic when it is 30 or lower outside and not have much much ventilation

it would certainly be the least expensive way to go , no change to the roof , very minimal labor and materials , just remember to remove them in the spring and put them in before the first big snow.

could even staple some tar paper up to make a better seal , just staple it above the opening so you hold it up slide in the gate and if some snow gets in under the vent between the vent and the gate it should be minimal


one other idea is you know it is going to come in , direct it back down to the eves so it can melt and run out
https://www.menards.com/main/buildi...7.htm?tid=1622408569775652069&ipos=6
this is valley tin , 20 inches wide 10 feet long screwed with some washers to the under side of the rafters it could drain any melting snow bac down to the eve were it could run out if vented

if the 10 foot valley tin was to hard to move into the attic you could do it with roll tin also

might even just be able to add some baffles so that it piles up only a couple inches before the snow fully plugs the vent and no more can come in , this could melt and only be a very little water you baffles could be bent tin open top boxes , that leave a inch or 2 gap top and bottom from the under side of the roof deck with a weep hole in the bottom that lets them drain into buckets hung below

air can turn right angles but it is a lot less likely to bring snow with it as it has to slow down to do so. once enough snow fills the pan it would plug it up

Rally, Thanks I will pass that on to her. Expense is not the issue. She has insurance that covers it. She is friends with the insurance agent and last time ( a year ago ) they got a new roof, new vents, old insulation out, new insulation in, new sheet rock ceiling and painted. They put the vents in he suggested, so he is kind of stuck paying to fix the problem. She just does not like the house trashed, even for new and replaced.