How To Vent an Attic Without Soffit Vents

The standard intake vent for attics is a soffit vent (also sometimes referred to as an “eave vent”) and it allows for air to enter the attic down low, near the eaves. Intake air is critical to maintaining a proper flow of air throughout the attic space. Air enters low and then escapes out of the attic higher up near the peak of the roof, usually via a ridge vent, an attic fan (which we do not recommend), static roof vents, or a high-mounted gable vent/fan. Remember, it’s a bad idea to mix exhaust vent types (passive vents with active fans). More info that here: Proper Attic Ventilation

Image Credit: Fine Homebuilding

Even without soffit venting, it is important to provide an air gap at the soffit level to help keep the roof deck dry. For more information on ventilation and moisture control, read this article I wrote on Proper Attic Ventilation. It’s my position that you should have a proper ventilation system in your attic and that you should always take the time to air seal the floor of the attic (sealing off the living space from the non-conditioned attic space), but in cases where you don’t (or aren’t able to), I want to offer some information and direction.

What do you do if your attic doesn’t have soffit vents and you are unable to add them?

First, let me reiterate that I think you should use soffit vents as your intake source for attic ventilation. If your house has minimal (or non-existent) overhangs that won’t accomodate soffit vents, or you simply aren’t able to install them for some reason, then you have a couple of options to provide intake air inlets low near the roof perimeter.

The two most common options are to:

  1. Install low gable vents located above the top  level of the attic ceiling insulation
  2. Use “eye-brow” vents that are on the top of the sloping roof surface near the soffit/eave area.
  3. Focus on the other ventilation you have in the attic.

If you are installing a new roof, consider a drip edge vent. This will allow air to come in under the edge of the shingles, and then enter the attic via a small slot/cut that is about 8” from the edge. Learn more here.

Various exhaust vents can be used in conjunction with low gable vents and “eye-brow” inlets. For example, you can use ridge vents, mushroom cap vents, upper gable end vents/fans, high mounted attic fans, etc. Remember, your main goal is to get air moving through the attic by entering the attic space down low near the overhang/eave level and leaving the attic near the peak of the roof.

Using Gable Vents

For an attic without soffit vents, you may have the option to use gable vents instead. Typically you would have a gable vent on each end of the attic. Normal vented air likes to enter the attic lower down (near the bottom third of the attic ) and as it passes through, it will exit higher up near the top third of the attic space. If you have an attic with no soffit vents but 2 unobstructed gable vents, then you will probably be ok on ventilation. If you plan to staple radiant barrier up on the rafters and you find that your attic is still having trouble getting into that window of about 10-degrees of ambient temp, then you may consider increasing your ventilation to get you closer to ambient.

Using Low/Eyebrow Vents

If a gable vent seems like too big of a commitment or undertaking, consider smaller eyebrow vents that are mounted low on the roof slow so they can act as intake vents. Remember, you want more entry points at the perimeter (bottom) edge of the roof than you want at the exit points at the top of the roof. Most people have plenty of exhaust vents but not nearly enough *intake* vents.

Should You Add a Ridge Vent?

Maybe you’ve considered adding a ridge vent because you’ve heard they’re a good choice but you’re not sure since you don’t have soffits. Let me spare you the headache, if you don’t have soffits, don’t install a ridge vent. A ridge vents works by drawing air upward and out of the attic space. But if you have no intake, where is the ridge vent going to draw the air from? 9 times out of 10 it’s gonna come from your leaky attic floor. This is a huge energy waster that I discuss more in this article: Comfort and Energy Efficiency Tips.

Another option for homes that have no place for intake vents would be to use a modified solar fan. You will reverse the wires to make the fan blow INTO the attic as your intake.  If you go this route, you will need additional vents to allow the air to get OUT (I recommend you use static vents for this purpose).  This method is called “positive pressure ventilation” and should only be used as a last resort.

Source: Pinnacle Exteriors Inc.

Summary

Do you need ventilation in order for radiant barrier to work? No. Radiant barrier does require and air gap to work to reflect heat, just an air space/gap. You can learn more about how that works here: Why An Airspace is Required for a Radiant Barrier.

Ventilation is important and can help keep an attic dry and lower air temperatures, but not having any ventilation isn’t the worst case scenario. If you don’t have soffit vents, we recommend you add some other vents in the lower part of the attic that can function like soffits. For some homes, you could try adding vents to a porch ceiling that could act like a soffit and feed the attic. If none of these options are possible, then we suggest you focus your attention to making sure the floor of the attic space is air-tight by checking ductwork (if applicable), lights/fans/vents protruding wires or hardware into the attic, and any other area of the attic floor where there are openings/holes/seams. A couple of cans of spray foam can go a long way toward helping keep things sealed up air tight.

Remember, what really matters is doing everything you can to make sure that the ceiling under the insulation has no air leaks into the attic, and this is a good practice whether or not you have attic ventilation!

12 thoughts on “How To Vent an Attic Without Soffit Vents

  1. I need help! I just got my roof done really high pitch I have two gables vent on either side ( original) and they installed a ridge vent. I have mild growing probably from before the roof was installed. Will two gables and a roof vent be sufficient. Should I be installing an electric fan?

    1. If you have plenty of intake into the attic (usually via soffit vents), then your ridge vent should work well. However the mold is a concern, so I’d recommend either checking yourself or hiring a professional to come take a look at the attic floor and find the “weak spots” where air could be leaking through so they can seal them up. This is hands-down one of the most simple but effective ways to save energy and stop moisture problems in the attic – air seal that floor as best as you can!

  2. Hi Ed,
    My home is English Tudor styled and has no overhang/soffit. We also have a furnace and ductwork in our attic. The ductwork has been sealed and insulated. The attic floor is also insulated. We have 3 roof vents, 2 gable vents, a roof fan and a ridge vent. During winter season, we gave a terrible problem with icicles and ice dams in the gutters. We’ve had several roofers out for suggestions and so far none have worked. Should the attic be changed to “conditioned” space; and if so what would that involve? Please HELP!!

  3. We have a 1940’s Mansard roof with NO soffits. We are replacing the roof in a couple of weeks. The attic runs hot. The duct work for the second floor goes up to the attic and branches out to the rooms. The attic has a wood floor and minimal insulation. The rafters have none. I have two contractor proposals. One wants to add the ridge vent. The other wants to keep the current type of vents which are turtle vents. The attic currently has NO mold or condensation. What should we do?

  4. Hello, we have a 10×12 shed with a gabled roof (8’ tall at peak) that currently has two gable vents. There are no soffits and no way to add soffit vents. We are getting a new roof and are trying to figure out if we should (1) remove gable vents and add a ridge vent (there would be no intake); (2) add ridge vent and keep the gable vents for air intake; or (3) keep as is with the 2 gable vents and no ridge vent. We are in Houston, so often hot and humid weather. We do have a few spots of mold on the ceiling above the door and above one of the windows, but it wipes right off the painted surface. We used to have a shrub in front of the gable so it could be from that.

    We are leaning toward (2) above but would really like an expert opinion. Your input would be appreciated.

    1. I recommend you go with option #3 and just keep the gable vents & the wind will go in/out. On a small shed that size, a ridge vent won’t make a difference compared to the existing gable vents. There is no way to totally prevent mold in a non-conditioned building, but decent ventilation (via gable vents) will help some.

      Being in Houston, I definitely would recommend you install AtticFoil in the shed to make it much cooler in summer. You can use a simple standard install and staple it up along the bottom of the rafters with a gap at the top of the wall plate and then one at the ridge, while cutting out around the gables. You can see an install here: How to Install AtticFoil in a Shed

  5. Hi Ed, Hoping you can help me out with my situation. I ran into an excessive amount of ice damming this year with my property. I had additional blown insulation added, although I was told by the insulator that my R value was already quite good and that things appeared to be sealed properly in the attic. The insulator recommended additional gable vents and a few maxi roof vents be installed to assist with getting hot air out of the attic.

    I own an older home that does not have eaves ventilation and would be very difficult to have this ventilation added. The home currently has 1, 12×15 rectangular gable vent per side of the home and a couple of small mushroom type roof vents.

    I am getting mixed signals from those in the home building industry and the internet, some telling me not to install both gable vents and maxi roof vents as they conflict with each other in getting hot air out, some telling me just gable vents or just maxi roof vents.

    Not sure what to do…

    I appreciate the help.

    Brock

    1. Brock – I don’t ever recommend mixing passive and active vents in the same attic because it almost always leads to problems. Take a look at this article I wrote about the basics of attic venting and see if that doesn’t clear up some of the confusion: Attic Ventilation 101

      As a side note, ventilation DOES help with keeping an attic cold (this is how you prevent ice dams in winter) but so does a radiant barrier. I cover how AtticFoil can help with ice damming on this page: How SuperPerf Helps Prevent Ice Dams on Your Roof
      Hope those resources are helpful to you!

  6. Hey Ed,

    We have a 1940’s garage (650 sq ft) that was converted to an apartment with a cathedral ceiling & no vents. Is it worthwhile to install soffit vents and a ridge vent if there is no air channel? We suspect that there is old fiberglass insulation between the roof and the ceiling. Wondering if a minimal amount of airflow through the fiberglass is better than none? We live in Boise. Any thoughts would be much appreciated.

    1. No, I don’t think the lack of vented air is the problem here – it’s the radiant heat coming in from the roof and it having a pretty direct route to get right into the room. I do think it’s worthwhile to re-do the cavities and incorporate radiant barrier as shown here: Installing AtticFoil in a Cathedral Ceiling for Maximum Comfort

      Remember, walls don’t have ventilation and they can still perform well; ventilation isn’t always the answer. I dive into this topic more on this page: Surface Temps vs. Air Temps (Why ventilation can’t solve it all)

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