# Open Eaves Soffit and new blown insulation



## handy man88 (Jan 23, 2007)

Those gable vents are right at the top edge of the insulation, so maybe you don't need to add any soffit vents.

What is your R-value?


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## mpierce9 (Mar 30, 2011)

The vent in the image is one I cut under the eaves. Its what i would like to repeat. I brushed the insulation away from the outside. The insulation R value is R38. I would like to close the gable and add soffits due to my understanding that ridge vents and gable vents don't work well together.


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## handy man88 (Jan 23, 2007)

mpierce9 said:


> The vent in the image is one I cut under the eaves. Its what i would like to repeat. I brushed the insulation away from the outside. The insulation R value is R38. I would like to close the gable and add soffits due to my understanding that ridge vents and gable vents don't work well together.


OK, well put some more vents in.

I think you need to determine the exhaust of your ridge vent and calculate the intake needed to make it balanced. Someone who responds often here has some website that provides that info.

What part of the US are you located?


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## mpierce9 (Mar 30, 2011)

Thank you for the reply, and I do plan on adding more vents. I live in Atlanta GA as mentioned. My initial question still stands though, do I need to add baffles for the vents given my current situation, or can I just push the insulation to the side once I cut the vent?


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## handy man88 (Jan 23, 2007)

mpierce9 said:


> Thank you for the reply, and I do plan on adding more vents. I live in Atlanta GA as mentioned. My initial question still stands though, do I need to add baffles for the vents given my current situation, or can I just push the insulation to the side once I cut the vent?


I would only add baffles if you need to keep the insulation pushed back to prevent the obstruction of air flow. If there's a chance of blockage, I would add the baffles. 

There was someone who posted here who had the same issue as you, but instead of cutting out a rectangular vent, he cut out circular holes and ran pvc pipes, I think.

This vent theory does work in theory, albeit very slowly.

Consider adding vents, but closing off both the gable and ridge vents, and then add a power vent so you have active, vice passive, venting.


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## [email protected] (Nov 17, 2008)

You should add some type of baffle to keep the insulation from falling and blocking the soffit vents. You can get wind blowing into the soffits that might disturb the insulation.

More venting is better. Add the soffit vents and keep both the ridge and gable vents for passive ventilation, and possibly add a power roof vent if the heat is too much. You can find more attic ventilation info here; http://www.roofingcontractorreview.com/Roofing/Attic-Ventilation/Roof-and-Attic-Ventilation.html


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## mpierce9 (Mar 30, 2011)

So the suggestion is to risk compressing the attic insulation in order to add baffles into the eaves vents and to leave the gable vents, ridge vents, new cut eaves vents all open and possible add a power fan?


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## handy man88 (Jan 23, 2007)

mpierce9 said:


> So the suggestion is to risk compressing the attic insulation in order to add baffles into the eaves vents and to leave the gable vents, ridge vents, new cut eaves vents all open and possible add a power fan?


Intake is very important.


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## trom120 (May 13, 2011)

mpierce9 said:


> So the suggestion is to risk compressing the attic insulation in order to add baffles into the eaves vents and to leave the gable vents, ridge vents, new cut eaves vents all open and possible add a power fan?


I can't speak to the question regarding the risk of compressing your insulation, but please ignore the advice that someone gave about combining different types of exhaust vents for the same attic space.

Because of the so-called stack effect (i.e., hot air is less dense and travels up in an attic), you need to establish a single "low point" for intake and a single "high point" for exhaust. By single, I mean that all your intake vents should be at one elevation (at the soffits or undereaves) and all your exhaust vents should be at one elevation (say, a ridge vent at the top only, with no additional exhaust vents below the ridge). If you use turbine vents, for example, you want to place them all at the same distance from the ridge (not one in the middle of the slope, and another at the top).

Otherwise, you are likely to encounter a situation where the air "short circuits". Air might come in through the gable vent (which is supposed to be exhaust) and out the ridge vent. That reduces the effectiveness of the "washing" effect that you want, where air comes in from the soffits and up to the ridge vent.

Don't take it from me, though. The link below is from Lomanco, a reputable manufacturer of venting products. Read the Do's and Don'ts section.

http://www.lomanco.com/VentilationGuide/ventguide.html


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## Dale Chomechko (Mar 11, 2008)

You have the right idea, just buy a couple bags of loose fill insulation to repair your squashed insulation as you leave the attic upon finishing your task

Dale Chomechko
DC Roofing Inc


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