Attic insulation and soffit vents

Is it okay to have the insulation go all the way to the eaves, if there is not a soffit vent within those joists? If you can’t get to the edge then it is hard to tell where the vents are. I did see another topic where Scott shuts off any lights to look for sunlight. Thx Kevin

I’ve seen insulation to eaves.
Many plans have insulation to eaves even with ventilation vents.
Blocked vents would be a problem.
If no vents. You want the most insulation as possible to prevent ice dams

Morning, Kevin.
Hope this post finds you well.

The term is daylight.

The insulation is laid atop of ceilings, or blown in, to form an even blanket, and ‘should stop’ at/above the wall assemble, not progress over the soffit.

Attic insulation dams are manufactured and installed between rafters or trusses to prohibit just that. An insulation blanket from covering the soffit. That is not a complete explanation. Insulating and venting roof and attic spaces is a science.

I do not enter attics unless I really have to. I inspect from the hatch.
The reason I invested in a powerful cameras, so I can take defined closeups and limit my liability.

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Good picture and exactly how insulation is supposed to be installed.

Any insulation that is against the roof sheathing without a baffle, is stopping air flow and a recipe for problems.
I often find where an installer blew cellulose in right out into the soffits and against the roof panel. Its a lot of labor to fix.

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Welcome to our forum, Kevin…Enjoy! :grinning_face_with_smiling_eyes:

Roy gave a good picture so I would recommend installing soffit vents:


Many older homes don’t have vents. Ie bungalows and such. I don’t buy into the venting theory that it causes problems. The older homes often have plank sheathing so the gaps between boards provide ventilation.

So this is my older home response.

I just put in vents on a attic that had blow in insulation stuffed between rafters. There wasn’t any signs of moisture problems. Still added ventilation but I would of thought there would be some issue :thinking:

The blow in had to be 30 years old or more

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Adding insulation is NOT always the answer. Once you’re at a specific R value thickness, you’re wasting money adding more.
Roof venting is critical to roof life, both shingles and often structure. In addition, ice damming and the resulting moisture intrusion, will cause serious issues if its not addressed.


When you walk around the exterior, take a mental note of vents in any visible soffit. Then once you are in the attic, look for something resembling what Roy posted and turn out the lights. If the vents are open, daylight should be visible.

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I don’t know my roof is 120 years old

You are correct, not always, but if there isn’t venting more insulation prevents the condensate and ice dams.
Ie cathedral style without vents

Incorrect. Check out the insulation and roof construction standards for your area.
Energy code here in our climate zone in Michigan dictates R49.
Is higher recommended…sometimes. But throwing or blowing more in doesn’t prevent ice damming.

Check out air sealing and proper insulation methods online. JLC has an excellent posting/article.


Eh not interested

They didn’t build houses as tight back then and the wind whistled through the attic. So, ventilation was there already.

Yep. But depends who you ask about no ventilation in cathedral spaces

If the snow can’t melt then no ice dams can form is what I am saying. Plus the pitch and materials of roofing play a part. Steep roofs shed snow off roof quickly.
Metal roofs actually sometimes have to have measures to slow the snow coming off for safety