attic ventilation: almost no eaves

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Just bought a house in New England.
The home inspector said the attic ventilation was inadequate. First, the ridge vent wasn't big enough. Second, he said there were no soffit vents.
Just eyeballing things from underneath, the eves are very, very narrow. How could soffit vents be installed if there's almost no soffit?
Also, is a roofer the best type of contractor to look at attic ventilation?
TIA,
S
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Describe "very, very narrow". 1"? 2"? 3"?
Soffit vents can be installed by cutting away all of the wood on the underside and then covering the gap with slotted vinyl like this:
http://images.lowes.com/product/715751/715751903202.jpg
Those vents can be trimmed to fit, but not knowing what you mean by "very, very narrow" I can't say if those will work for you. You could add gable vents, even powered gable vents. They are not as efficient as soffits vents, but they should help.
http://tinyurl.com/ojulw4g
http://www.doityourself.com/forum/attachments/basements-attics-crawl-spaces/17306d1378410170-ridge-vent-powered-gable-vent-picture-inside-house.jpg
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Really? Mold in the attic or elsewhere in the house is the only reason to ventilate an attic? Perhaps you should do a little research before answering attic ventilation questions. Here, I'll help you out...
Stolen without permission from https://www.energystar.gov/index.cfm?c=diy.diy_attic_ventilation
Natural Attic Ventilation At first it may seem odd to add insulation for warmth and then purposely allow cold air to enter the attic through vents, but this combination is the key to a durable and energy-efficient home. Here's why: in the winter, allowing a natural flow of outdoor air to ventilate the attic helps keep it cold, which reduces the potential for ice damming (snow that melts off a roof from an attic that is too warm and then re-freezes at the gutters, causing an ice dam that can damage the roof). Proper insulation and air sealing also keeps attics cold in winter by blocking the entry of heat and moist air from below. In the summer, natural air flow in a well-vented attic moves super-heated air out of the attic, protecting roof shingles and removing moisture. The insulation will resist heat transfer into the house.
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On Sunday, June 15, 2014 9:37:20 AM UTC-4, DerbyDad03 wrote:

+1
Mold isn't a reliable indicator of whether attic ventilation is sufficient. Plus a big factor here is the inspector said there is a ridge vent that is too small and *no soffit venting*. I'd like to see a building engineering or code reference that says that's an acceptable ventilation system. Every credible source, roofing supplier, etc will tell you that with a ridge vent you also need soffit vents of equal capacity to allow air to flow via convection.
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....large snippage occurred....

That is not necessarily true. There are differing opinions on the Short Circuit theory...
I've posted 2 links below. One says never mix gable vents and ridge vents while the other claims to debunk the short circuit myth. There are many other articles taking both sides of the question. I'm not saying who is right and who is wrong, I'm simply saying that claiming that "nobody thinks" you should have both isn't true.
Granted, I don't know that anyone would actually install soffit, ridge _and_ gable vents from scratch, but gable vents and ridge vents are not mutually exclusive.
http://www.airvent.com/pdf/literature/TipsBooklet.pdf
http://www.roofingcontractorreview.com/Attic-Ventilation-Help/Roof-Ventilation -|-The-Short-Circuit-Myth.html
Personally, when I had soffit and roof vents installed with my new roof, I closed off my gable vents based the recommendation of my roofing contractor, but that was before I read any of the differing opinions on the Short Circuit theory. That said, I'm not planning on opening them back up.
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On Sunday, June 15, 2014 10:19:17 AM UTC-4, DerbyDad03 wrote:

I couldn't get the Air Vent link to open on this PC, so I'll have to take a look at it later, but I assume it says that you should not have both gable and ridge vents. I did look at the other link. I have wondered what the exact effect of having both gable and ridge vents together would be and I would say that I never fully bought the short circuit idea either.
In the current discussion, the OP already as a ridge vent, and apparently no gable vents. In that context, the suggestion was made that for a typical gable type roof, gable vents should be used. I should have said was that I don't know of any credible source that would tell you to add gable vents to a house that already has a ridge vent. I think most "experts" would tell you to close off the gables if you install a ridge vent. Per the model video, that may not be necessary and I often thought if hot air is rising, that the gable would just offer another way out. That;s what the model video shows. But also, if you look at the smoke in the video, it appears that on the end closest, little smoke is coming out of the ridge vent near the gable vent. That would suggest that while in that model the gable vent isn't hurting, it may not be helping either, because air just comes out it instead of out of the ridge vent.
So, I can see not closing off existing gable vents. What I disagree with is Homelessguy's idea that gable vents are the best solution for that type roof and the implication that the OP with a ridge vent should be looking at gable vents. Clearly his main problem is no soffit vents and maybe an inadequate ridge vent.
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As part of my roofing contractor giving me the quote for his work, he suggested that I install the foam baffles after he cut the soffit vents and installed the ridge vent. Knowing the cramped layout of my crawl space attic, I (jokingly) asked him how much he would charge me to do it. He laughed and refused to give me a number. I'm sure he would have if I had pressed him, but he also knew I wouldn't go for it.
It was one of the sweatiness, dirtiest jobs I've done in a long time. Crawling on top of insulation, dressed in long sleeves, long pants and wearing a dust mask, squeezing between the rafters while lying on my back and reaching as far down as I could to staple the baffles in place. It really sucked, but I knew I had to do it or the money spend on having the soffits cut and the ridge vents installed would have been wasted. The difference between soffit and ridge vents vs. the gable and box vents I had before is tremendous. It is so, so much cooler in the attic.
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Some ridge vents span the entire width of the roof. Mine does. Mine is a GAF Cobra product, this link is to an OwensCorning model, so full width ridge vents are common across manufacturers.
http://www.owenscorning.com/roofing/accessories/ventilation/4-foot-strip-heat-moisture-ridge-no-weather-protector/
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On Monday, June 16, 2014 3:54:19 PM UTC-4, DerbyDad03 wrote:

You're right, having the ridge vent product span the entire peak is typical. And it makes sense because it looks uniform. We were talking about the ridge vent being inadquate and what I was thinking of when I typed that was where the *cut for the opening* ends. With a typical install the opening will stop well short of the end of the roof. One good reason is that you don't want to cut into the eaves, only into the attic. And you want to leave some extension of the ridge vent past the attic opening so wind driven rain can't get in from the end. But you're right, he can't see that from the ground, only the attic.
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DerbyDad03 posted for all of us...
And I know how to SNIP

Welcome to home ownership. This is a job for a day laborer.
--
Tekkie

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On Sunday, June 15, 2014 7:44:54 AM UTC-4, snipped-for-privacy@gmail.com wrote:

Big enough how? Length? Width?
Second, he said there were no soffit vents.

How narrow? If you can get a 2" wide continuous opening to put a vent in, that's probably minimal, 3" wide or better should be fine. A ridge vent typically has about a 2" wide opening at the top. You need something comparable at the soffits.

That would be my first choice, especially if it involves the ridge vent. But this stuff is pretty basic and within the skills of many home repair contractors, DIY, etc.
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snipped-for-privacy@gmail.com wrote:

Woburn Mass?

Look at this picture and tell us what type of roof you have:
http://cloud.homedesignersoftware.com/1/images/design-articles/roofing-styles/roof-styles.gif
If you have a gable roof, or gambrel roof (sorta looks like a barn roof) then you install vents in the gable ends.
If you have a hipped roof (with no gable ends) then unless there is absolutely no soffit possibility (ie - there is no roof overhang) then I guess you could install vents along the lower edge of the roof line:
http://www.single-family-home-remodeling.com/images/low-profile-roof-vents.jpg
I've never seen vents like that installed along the *lower* edge of a roof line, but it might be your only option if you really don't have any roof overhang where you can install intake vents.

Roofer's typically don't know shit when it comes to engineering new ventilation solutions. They can replicate what was there originally when replacing a roof, and they can replicate what they've seen on other jobs.
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On Sunday, June 15, 2014 9:00:05 AM UTC-4, o m e H o m e G u y wrote:

Not only can a ridge vent be used in the gable roof in that link, but a ridge vent is the preferred and better solution.

It's not a choice between gable vents or soffit vents. Gable or ridge vents allow hot air to exit. Soffit vents are there to allow cool air to enter from below.

If there really isn't any space for soffit vents, which I doubt, there are still other solutions that are better than putting ugly box vents all over the lower portion of a roof.

Nonsense. Knowing about correct ventilation is a key part of any competent roofer's job. It's part of the training they receive from roofing systems manufacturers, part of the warrantee for roofing products, etc. That's how it works in the USA. Don't you Canadians know about correct roofing?
They can replicate what was there originally

And you think a competent roofer who's been in business for even a couple years hasn't seen attics that didn't have proper ventilation and needed it added? If anyone doesn't know WTF they're talking about, it's you. You showed him a pic of a typical roof where a ridge vent is the recognized #1 choice of experts and you proceeded to tell him to use gable vents. And if that's not bad enough, he even already has a ridge vent. Nobody thinks you should have both a ridge vent and gable vents. Good grief.
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On Sunday, June 15, 2014 9:00:05 AM UTC-4, o m e H o m e G u y wrote:
<snip>

Heh. Good guess. Winchester, actually, right next door.
<snip>
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On 06/15/2014 07:44 AM, snipped-for-privacy@gmail.com wrote:

Or maybe your home inspector is just trying to justify his large fee.
If you don't have mold in the attic or elsewhere in your house then you probably don't need more ventilation.
Personally, I'd just make sure the full bathrooms have working exhaust fans that actually exhaust outside.
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On Sunday, June 15, 2014 7:44:54 AM UTC-4, snipped-for-privacy@gmail.com wrote:
<snip>
It's a gable roof. There are no gable vents, though on each gable end ther e's a smallish window.
Not sure what the inspector meant by the ridge vent not being big enough.
Eaves narrow: it's hard for me to see---the house is pretty big with two s tories (I'll open a second floor window and peer up, but I can't do that ri ght now because the polyurethane is drying on the floors there which we jus t had finished). But it looks like a gutter, then a fascia board, then som e kind of moulding. Just looking at it from below w/o binoculars, and assu ming the measurement is between the wall and the fascia board, it looks lik e 1".
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On Monday, June 16, 2014 9:29:19 AM UTC-4, snipped-for-privacy@gmail.com wrote:

ere's a smallish window.

You should be able to see the length of it from the ground. It should span the whole peak, with the exception of the last two feet or so on each end. Width wide you can check from the attic. The gap is usually 1" on either side, about 2" wide total. It would be kind of odd for it to not be wide enough. It's just as easy to cut it the right size as making it small.

stories (I'll open a second floor window and peer up, but I can't do that right now because the polyurethane is drying on the floors there which we j ust had finished). But it looks like a gutter, then a fascia board, then s ome kind of moulding. Just looking at it from below w/o binoculars, and as suming the measurement is between the wall and the fascia board, it looks l ike 1".
There are products that may work for those cases:
http://www.gaf.com/Roofing/Residential/Products/Roof_Vents/Cobra_FasciaFlow _Vent
That's one example, if you google for fascia vents you can find others. How hard it is to install on an existing roof would depend on what's there now.
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On Monday, June 16, 2014 9:45:18 AM UTC-4, trader_4 wrote: <snip> http://www.gaf.com/Roofing/Residential/Products/Roof_Vents/Cobra_FasciaFlow_Vent </snip>
Thanks, I'll bear that in mind.
Thanks everyone for the replies.
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Bob F wrote:

I made the exact same suggestions you did.
Trader-4 went ape-shit on my suggestions (after first misinterpreting them).
Trying to retro-fit some sort of "micro-soffit" solution in a home with some arbitrarily small potential for eve ventilation is likely to give a poor cost / benefit result.
The OP never did come back and give any sort of dimensions for his eves / soffit.
Throwing in a few gable-end vents (low, as I said before and as you're saying now) is likely to be an acceptible solution for a house that apparently has little to no intake path as it is.
When it comes to ridge vent vs power vent, I'll take power vent because on those days when you really need to shed attic heat, there will be very little ambient outside airflow, rendering passive diffusion or drafting of air through a ridge vent of little use or effect.
But the OP already has ridge vents.
So maybe a powered gable-end vent (pulling air in) will be just as good (or superior to) passive intake flow through paltry soffit retro-fit.
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snipped-for-privacy@gmail.com posted for all of us...
And I know how to SNIP

Ok

If you ask he won't quote any specifics.

1".
I would recommend as much soffit venting as possible with the insulation spacers mandatory. Do not use the little 2" dia buttons they use a hole saw to install, they are useless.
I believe in the short circuit theory just as a common sense thing (to me). I have done no research as DerbyDaddy did.
--
Tekkie

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