How to Check if Your Soffit Ventilation Baffles are Working (from your attic) 

Yes! Before you do this you definitely need to first look at the roof and find a spot where there are no nails.

A lesson you learn only once!

Good observation Matt you're correct, it does not confirm that they are drawing air in through them. In order to do that you would typically need to employ a smoke generating device, like a smoke pen that an energy auditor would use to confirm that air is in fact being pulled upward and out through the upper ridge vents (or whichever type of exhaust ventilation you have). I didn't do that in this video because the vast majority of the time that we encounter ridge vents in homes, they have been cut in properly and are doing their job (it's just a matter of whether they are drafting their air from soffit intake vents or the home itself --- a highly non-ideal --- but common issue; especially when there are no intake vents present). That said, establishing that your soffit vents are open to the outside is the biggest first step in my opinion, and a question that comes up often from our customers. Thanks! Andy

We see this sort of thing ALL the time. Just because baffles are present, or you see a soffit vent installed from below, does NOT mean that it is open and functioning. The continuous under shingle vents for air intake have been a tremendous new solution that we are big fans of here. Andy

Yes, the closer that you can get to the suspected soffit vents the better for sure. We see many "perforated" soffit panels that have solid wood beneath them, so they only appear to be open to the attic. When you go up to the attic to inspect them and look down into the eaves/ soffit area -- it is pitch black. Andy

Welcome!

Hi Jacob, I would say that you do not. If you are able to see daylight than you definitely have a clear air channel that is allowing air to move upward into your attic. You should be good. However, this could also indicate that you do not have enough insulation. We insulate to R-49 using cellulose insulation which is about 15" inches deep. Often when I can see daylight through the soffit, the attic is insufficiently insulated, but this isn't always the case. Thanks! Andy

@@insulwiseenergycomfortsolu3293 Thanks for your reply. That makes sense about lacking insulation. I’ll check out my situation closer. Thank you!!

Keep in mind that over time that blown-in insulation can fall down and block the soffits, particularly if someone is moving about in the attic kicking the insulation around. Also, I have found that baffles provide a chimney effect channeling the incoming air upward where it removes the heat from the shingles. Taken with an IR heat gun, there can be as much as a twenty-degree difference between the baffle and the hot air exiting it at the top. Baffles help move the heat up and out.

​@@Inkling777 Correct and great observation. When we install baffles we first staple them into place, then insert a piece of fiberglass between the baffle and the exterior wall top plate to keep insulation from getting into the soffit vents that way. But you're right, we've seen many blocked soffit vents over the years from people moving around and disturbing the blown in material. However if the baffles are installed high enough above the insulation, you shouldn't encounter that too often. Thanks for the comment! Andy

Thank you for watching our videos! We install insulation at edges of the attic intensively. This is where the roof is closest to the ceiling below, and if this area is not well insulated you can have ice dams and melt spots form on the roof when it snows. If your attic has been effectively air sealed and properly ventilated, you shouldn't have excessive condensation in that space. And it shouldn't form where the insulation meets the top of the baffles so long as the soffit vents are open and performing properly. Hope this helps! Andy

@@insulwiseenergycomfortsolu3293 thanks for getting back. I wonder why that is though? Insulation is literally touching the rafters and roof at that particular point?! So there's no air getting at that particular point where the insulation literally touches the roof and rafters at the edge. Yes the loft would be otherwise ventilated so air would get to every single other part of the roof and rafters as no insulation would be touching the rafters and roof elsewhere. I'm not claiming that condensation would form there I'm curious as to why it doesn't.. No ice here in Ireland, but cold weather all the same.

@@mryan4452 Condensation issues do not happen in all attics, even in cold climates. If that portion of the roof is oriented to the south or east it may be getting warmed from the sun. There may not be enough water vapor present to cause condensation issues. Also, just because insulation is present doesn't mean that there is no air flow. Most forms of attic insulation permit air to move right through them. Any blown in insulation will, and rock wool and fiberglass insulation also allow air to move through them at various levels. This could allowing some evaporation to occur. I'd also say that if you don't see a problem there, and we've just come through the winter, that you probably don't have anything to worry about.

Ok, so you've got a complicated situation there. There are a couple of things to consider when it comes to attic ventilation. Number one is that it is NOT a perfect science, and number two is that every house is different. That said, there are consistent "best practice" recommendations, and that is what we attempt to create when we work on our roofs and attics. The most important thing in my opinion is to first minimize the amount of moisture that is reaching your attic from inside your home (this is also assuming that you have a water tight roof with no leaks). You do this by making sure that your bathroom fans are ALL venting to the outside (and driers to if they are venting ot the attic --- yes, we see this here, ugh!). Secondly you want to air seal your attic floor as well as you are able to. I have another video for how to do this in an attic that is already insulated. After these considerations are addressed, ventilation is the next most important thing. I have seen MANY homes that ONLY had gable vents and were doing just fine. And if your home is aligned somewhat East / West, you will likely have a breeze pushing through regularly which is possibly the best type of attic ventilation --- in my opinion. Also, if you have been living in the home for a few years with that level of insulation, and there is currently no issue with attic mold, you are more than likely good to go. I would only recommend doing heavy duty retrofit work at this point IF you are having issues with heavy condensation on the underside of your roof or getting mold. Andy

Andy? Hope I got it right. I am so grateful for the reply and ideas. Yes, range, bath vents go thru the roof, sealed and wrapped with insulation. I like to plan for not just 10 years, but 100! After fixing cars it became an obsession like a decease I call perfectionism. Roof is dry, ridge vent running the length. I wish I had a vapor barrier behind the ceiling drywall but, in the 80's, I guess it wasn't important. This house & next door were show homes. So first ones built and different but I was told they are larger (Finished basements). With 4 kids, my wife is glad to have two levels. Wired design just like a 14k split level, instead, it is 14 feet apart. Then before I retired. I was holding 4hr tech seminars on vehicle systems in a different city Monday thru Thursday then drive home at 5-6 hrs. It was exhausting so after 7 years, Dr forced me to quit. But learned how hotels and shopping center were putting designs on the wall that added insulation on the outside. Not stucco, but EIFS. I had hard board sheets so marking studs, and 5" coated screws with 3" plastic caps held pink 2" R10. Then sand flat if not and scratch with a simple stainless steel brush, apply a fiberglass matt troweled into a thin layer of cement reinforced with chopped fiberglass and sanded smooth. Then you order the color and size of marble chips and trowel it on, just like drywall. It has a 2% fade in 20 years, so no painting. We pay 1/3rd heating & cooling after I did the entire house. Thinking any money spent on utilities is gone. The front is brick but dug to footings on West & East end using PL300. Water can't pass thru extruded but the white coffee cup expand can. This is now R14 and in Pueblo, I used dark brown on corners, extended rain on top of windows and doors with 3/4" foam backer rod on the edges of all. It cost more but I used building sealant instead of caulking because it's 300% more stretchy and comes in colors. You have to get a stainless steel trowel because anything steel could show up in the finish and look like a rust stain. Check EIFS.com and STO or Dryit. This is why I was looking into the power for roof vents to cool it down. Research! Thanks for the reply kindly. DK, Omaha.

Often we do, thank you.

It probably depends how many soffit vents you have. If you have plenty of soffit vents, but you're only getting half of each one that may not be bad. But if you just have a few vents than you probably want to maximize the air that you're getting from them. Andy

These are all good questions. Firstly, and this may be a controversial opinion, but we NEVER block gable vents. If your house has even a remotely east/ west orientation you should be getting a fairly good breeze through those things. Technically gable vents can disrupt the air current going from soffit vents to ridge vents, but I'll take positive air pressure via wind over "stack effect" in an attic every day. We have SOLVED attic moisture problems MANY times by unblocking gable vents that roofers blocked when they installed soffit and ridge vents. For blocking beneath the baffles we use fiberglass batts. The batts NEED to extend over top of the exterior wall top plate and the end of the baffles NEED to extend beyond the exterior top plate by a few inches just to be safe. You just need to be careful not to crush the bottom of the baffle when you push in the fiberglass. You can use a 2x3, crutch, or pole to nudge it into place. Hope this helps! Andy

Thanks so much Andy.. This is exactly what i will do!! Thanks again & God Bless you and your family!! L.T. Dan from KY

@@LTDan-pk3mx You are highly welcome! Andy

I would say that this is sometimes the case, but often for us it is not (sometimes the undersides of the soffits just get dirty over time). Being able to visibly identify a band of light at the bottom of the soffit baffle, or if you don't have baffles around the outer perimeter of the attic, is still for us the best way to confirm that your soffit vents are "open" to the outside. Thanks! Andy

Yup. I got burned by my builder's lazy installation of the original vents plus the neighbor's stinking cotton wood trees. Noticed soffit vents were no longer effective (attic couldn't breath). Became real obvious when one of the roof vents started sucking snow from top roof. Looked into louvered soffit vents - plugged with cotton. But it was only plugged by a 1 inch by 4 inch strip. Took off vents - that matched the hole size that the builder cut. 1"x4" opening for 8"x16" vents. Two slits from circular saw and beat with hammer, builders just don't care... When I moved in, I verified that I had enough venting based on assumption that builder cut a 7"x16" hole and the square inches size just barely covered the attic size and amount of roof venting. Add in the cotton wood junk and venting was down to nothing. Had to rework all the soffit vents because the builder was simply too lazy to cut proper openings.

Hi there, I am not familiar with the term suffix here, but I think you may mean soffit vent. If so, those vents will all allow air to be pulled upward into the attic (so long as you also have exhaust vents at the top of your roof). The effect will be to mix outside fresh air with the air inside your attic. This will reduce heat build up in the summer, and also reduce moisture build up in the winter.

Hi there, I don't know for sure about NJ, but my guess is the house designs are not tremendously different from Pittsburgh for the era. In Pittsburgh they didn't start installing soffit ventilation routinely until the 1980's. Prior to that if there was an overhang, it was solid wood with no ventilation 98% of the time. What you do often see are solid wooden soffits that are covered with updated aluminum or vinyl soffit that is perforated. The perforations give the indication that the soffit is vented, but the install teams almost never drilled holes into the wood prior to installing the perforated soffit, so it's just a decoration. You can have channeled soffit vents installed in your overhangs / soffits for sure and that would be a great idea. Or if you have a new roof put on have them install under shingle intake vents along with a ridge vent, that will take care of the issue as well. Hope this helps! Andy

​@insulwiseenergycomfortsolu3293 thank you so much, the ownerbhad just the roof replaced before we bought the house. It does not look like there are vents under the shingles. I will look into installing functional soffit vents.

It could be baffles, it could also be the wind causing the damper on a bathroom fan roof vent to "chatter." I have another video on this showing how this happens. It would be unusual for baffles to make enough noise that you hear them from inside the home -- but maybe. I would check out our bathroom fan vent video first. If it's not that my next suggestion would be climbing up into the attic with a headlamp on the next time you hear that sound, and directly investigating the source. Hope this helps! Andy

What did you end up doing ?

Hey sorry that I missed this. If they are blocked it is NOT easy to get them cleaned. If they are functional soffit vents and are blocked with insulation you will need to either rake out the blown in material, or tug the batt fiberglass out of the area. This is difficult work. If you pull the insulation back to far you then leave the edge of your home uninsulated or poorly insulated. You'll know this has happened if you see a melt line of snow around these areas in the winter time. Hope this helps! Andy

Lots of practice has given me a spider man sense for avoiding them! But yes, you want to look where you're putting your head before you put it against the roof deck. Nails hurt.

@@insulwiseenergycomfortsolu3293 lol