attic venting woes

[Hamilton Audio]

I noticed recently (on a house we've owned 2 years) that the blown in insulation in the attic was blown right into the soffit gaps. I am interested in improving soffit venting as i have a "wee bit" of faint frost on the main header in the winter and am hoping the AC won't work as hard in the summer.

So I got up there today with a scoop I made with sheet metal and a broom handle, hoping to pull out the plugged up gaps. It turns out that the batt insulation (with the paper on the back) was installed in such a way that it is stuffed into the gaps as well!!!!!!!! Its obvious this has been the case for the 20 years of this house's life.

I'm perplexed now....I've got 3 of the regular square type vents near the roofs peak, and a pair of about 24x24 gable vents (one on either side). I'm thinking about having two of the three top vents changed to turbine style, but am told that with plugged eaves, the turbines will make a negative pressure and draw household air into the attic.

What do I do? Is there sense in taking down some of the soffit/fascia and seeing if I can rectify from the outside? It doesn't look possible..... considering it has been this way for a LONG time and there doesn't appear to be any sort of systemic damage from it, I'm almost tempted to just install the turbines and say screw it.

any ideas?

b

[roger61611]

There may not be a significant gain in adding turbines, if either of these situations are true:

a) that the soffet vents are blocked b) that the ventilation is more or less ok

I would open up at least some of the the soffit venting and see how it goes next winter.

[Joseph Meehan]

I would want to open them up. Have you seen the various forms of baffles made to hold back the insulation? Could that work for you along with some sort of tool to pull back the insulation as you install them?

How about removing the covers over the openings and working from below, maybe with someone else in the attic?

It sounds like you are not getting buy with just slightly sub standard venting due the the existing vents. I would want to correct that.

[Jimbo]

What about installing ridge vents? My son did this last year after months of research and it certainly made a big difference in for his house. I then installed 30 feet of the same thing on my shop and I think it was a good investment.

Jimbo

[Joseph Meehan]

Ridge vents are great, I had them put in when my roof was replaced due to hail damage last year, but you need both low and high vents to create an air flow. You want the hot air to go out the top (ridge vents or gable vents) while cool air comes in the soffit vents. There can even be a problem when the mix of vents creates a short circuit so part of the area does not get ventilation.

[Hamilton Audio]

Yeah, I've seen those sytrofoam baffles - there are acutally a few in this house. Not many tho :( I traced back with the past owners of the house (who bought the house at 5 years old and owned it till 20 years old) and they confirmed they didn't touch a thing in the attic. That is, no adding or changing of insulation.

This leads me to believe that the insulation done was done from new or almost new. Not sure why they thought it was a good idea to block the vents! However, you can speculate that if after 20 years of being this way there is /really/ no issue, not sure I wanna rush and change thigns now - considering the work involved. If there was notable condensation in winter the insulation and roof members would show it - and they don't. I'm sure there is /some/ issue with heat buildup in the summer - which i'm sure adds to /some/ deterioration of shingle life....

but c>> I noticed recently (on a house we've owned 2 years) that the blown in

[stretch]

Wind turbine vents installed near the top of the roof will do about the same as or slightly better than ridge vents. Electric powered attic fans will pull a negative pressure on the attic which will pull air out of the house through any openings like ceiling fixtures, especially most can lights, I have never seen ridge vents or wind turbines do that. I have checked with a digital manometer to be sure.

Stretch

[Joseph Meehan]

I tend to prefer the ridge vents as they have no moving parts to make noise or go bad. That is not to say that in some situations they may not be the best solution.

[Beeper]

[Goedjn]

Well, it works BETTER with a ridge vent and soffit vents, but it's not actually necessary. If you have ridge vents and gable-end vents, then hot air will go out the ridge, and possibly out the down-wind gable, and replacement cold air will come in the up-wind gable and possibly the down wind gable. As long as there's a way for cooler outside air to get into the attic, it will pool on the floor, forcing the other heated air out.

Likewise with the turbine vents. They will not pull air out of your living space if there is anywhere easier to get it from.

[trader4]

"This leads me to believe that the insulation done was done from new or

almost new. Not sure why they thought it was a good idea to block the vents! However, you can speculate that if after 20 years of being this way there is /really/ no issue, not sure I wanna rush and change thigns now

- considering the work involved. If there was notable condensation in winter the insulation and roof members would show it - and they don't. I'm sure there is /some/ issue with heat buildup in the summer - which i'm sure adds to /some/ deterioration of shingle life....

But considering the job of evacuating the insulation from the soffit gaps (really, you HAVE to see this nightmare) i'm pretty sure i'll accept 5 years less shingle life in exchange :) "

Well what is it then that you're trying to do? Installing ridge vents or anything else isn't going to do much if you have no lower entry point for cool air to enter. Air that enters from gables will just go out the nearest ridge opening or other top vent and not do much to cool the whole attic. The basic flow that cools the whole attic and keeps moisture under control is cool air entry from below, exiting somewhere at the top.

It's not unusual for soffit vents to be covered with insulation. If you don't want to open them up with baffles and are willing to live with 5 yrs less shingle life, plus possible sheathing deterioration, then just leave it like it is.