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I recently opted in for an upgrade on my attic insulation. At an added expense beyond the bid I was given I opted in for the installation of baffles at the edges of the roof to stop the migration of the blown fiberglass onto the soffit and also to insure adequate ventilation of the attic. I have "turtle" type vents near the ridge and also have a thermostatically controlled power vent for the hot season. By design, the vented soffit is supposed to allow cooler air in from the outside under the eaves and the turtle vents to accommodate the outflow of the warmer air out of the top thus making for efficient venting of the attic.
My problem is that upon examining the job done by the insulation contractor, I find that he as allowed the insulation to cover the soffit thus closing off the influx of the air from the vented areas of the soffit. I live in a fairly dry climate (Northern Utah) but have concerns about changing the dynamics of the airflow.
I would appreciate hearing your thoughts.
Thanks
 

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I assume the baffles you mentioned should allow the air up from the soffit. They are also called proper vents.
If you look close you should see a thin foam panel between each roof truss. These hold the insulation back enough to allow are flow from the soffit.
 

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If the baffles are some sort of screen that is blocking the rafter bay, and the insulation is completely covering this baffle, then yes, the draft has been interrupted. Those baffles are meant to contain incidental overspray, and future settling of the insulation material into the soffit. They are not meant as a stop for the contractor to spray insulation against. Any blockage needs to be pulled away from the edges. The power vent might do this on its own, if there aren't gable vents, but it may just free the airflow in one or two rafter cavities, to get the air that it needs.
 

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Photos would help us to help you. In the diagrams below you can see that it would not normally be possible to see if the contractor had blown insulation out into the soffit if the attic baffles have been installed properly. How are you arriving at that conclusion?

Assuming that the insulation has been blown onto the soffit, how big a problem it is depends on how much of the soffit venting has been blocked. A photo of the underside of the soffit so that we could see what type of venting it is would be helpful.

Even in a dry climate, depending on the air sealing from the living space below there may be localized areas of high humidity (around a plumbing stack, for example) that can damage the roof sheathing. It’s a good idea to go into the attic in below freezing weather where the frost buildup will give evidence of that.

Since problems of localized humidity can be isolated to just one or two roof bays (areas between trusses), it’s important that soffit ventilation be continuous along the eave. That puts a bit of airflow into each bay to sweep air out to the vents (also why continuous roof ridge vents are better than “turtle vents”). So if the soffit vent is completely blocked in some area but completely open in others, the total attic ventilation may be adequate, but not the localized ventilation.

Chris
 

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This covering of the soffit vents is exactly what I found while updating the beach house (built in 1962).


Although it had soffit vents, the signs they were blocked showed up in the sag between trusses on the roof, and curled shingles. House had two gable cents, and a single power vent that didn't work. Way too much heat and moisture in that attic.


While changing things and having a new roof installed, I removed all of the soffit plywood, pushed back the faced insulation, installed foam baffles in every bay, then covered with vinyl using vented panels at every other panel.


Had the roofer install ridge vents, in addition to the small round replacement gable vents that I installed in place of some hideous vinyl venting covering the existing gable vents.


It IS noticeably cooler in the attic now, although on a hot, humid day, it still is not a place you want to stay in for long.:vs_whistle:
 
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