Vents in suffit

[hsmith13]

Hello, I am a honeowner in chicago land area that needs some professional help with an issue that is happening in our garage. We have 2 bedrooms and a bathrooom over a completely insulated 3 car garage. With extreme winds and polar cold the bathroom pipes froze. We accessed a panel in the garage ceiling and felt immense draft coming into the tiny 2 foot attic space that is from the garage ceiling to the second floor right above it. Upon looking outside we see a slanted small roof that has many vents in the suffit . Can we remove the vents or are they needed? The other issue those vents are causing is the outside air flowing right into our 3 rooms thru the walls. There is only insulation on the bottom of the attic space, bothing on the ceiling and definately no insulation on the exterior wall.
If we cannot remove the vents from the suffit for proper air flow and avoiding condensation then can insulate somehow?

 

[duneslider]

You don't want to remove the vents but you DO want to add insulation. Insulating isn't hard to do but if you don't feel up to the task find an insulation contractor, I actually think having insulation done is generally pretty affordable. I would also look and see if there are any rebates or incentives for insulating. Most areas of the country tend to offer insulation rebates.

 

[hsmith13]

You don't want to remove the vents but you DO want to add insulation. Insulating isn't hard to do but if you don't feel up to the task find an insulation contractor, I actually think having insulation done is generally pretty affordable. I would also look and see if there are any rebates or incentives for insulating. Most areas of the country tend to offer insulation rebates.

Thank you!

 

[K'ledgeBldr]

Not knowing the exact physical condition of your home’s framing, it would be hard to nail-down an exact cause. However, if your’s is like a lot of others that I have dealt with your problem isn’t unique.

If your home is less than 20yo, was built to code at the time of construction (permitted), your insulation is “most likely” adequate for your locale. Unfortunately, this cyclone bomb/arctic blast didn’t do a lot of people any good!

You most likely have an air/fire blocking problem/inadequacy. Insulation works best when it’s in “dead” airspace. If a wall or floor joist cavity isn’t blocked off from air infiltration, it’s basically just a filter. Soffit venting is for the attic/roof, so you certainly don’t want to eliminate it.

There has been a lot of information, analysis, and repair/rework about your situation. Try searching for “insulating a ‘frog’ (family room over garage)”.

I had a H/O many years ago that had apparently kept throwing money at the same problem from different vendors/subs. He finally got to the point to say "fix it!"- "fix it right!" So, the entire garage ceiling came down and no blocking- no air seal from the kneewall attics to the floor system/joists, The f/glass insulation came out- and the entire space/cavities were filled with foam. Not only did that take care of the air issue, it also more than doubled the insulation R-value.

 

[billconner]

A photo of the "slanted small roof" would be helpful. I'm just suspicious they are venting the attic space.

 

[K'ledgeBldr]

A photo of the "slanted small roof" would be helpful. I'm just suspicious they are venting the attic space.

I suspect this is the attic space behind kneewalls. And as I lamented to earlier, I suspect that there is no blocking at the floor joists directly below the kneewalls. This has been a huge problem over the years.

 

[larry4406]

I suspect this is the attic space behind kneewalls. And as I lamented to earlier, I suspect that there is no blocking at the floor joists directly below the kneewalls. This has been a huge problem over the years.

Agreed.

In our new construction we do attics via attic trusses.

This detail is rigidly enforced - blocking off the joist (truss bays in our case) planing out with the exterior of the knee walls. We spray foam this "band board" region as well to ensure no air leakage. Region circled in red in sketch below.

We use thermoply on the cold side of the attic knee walls and make sure all gaps are sealed with caulk/foam. Also use insulation vent at the area shown in green to ensure 1" air gap so soffit and ridge vent work. Sometimes this requires the truss bottom chord to be locally scabbed down to get needed depth for insulation thickness.

 

[billconner]

Was a thread here not long ago with a vented soffit and a little roof stuck on the wall about halfway to top plate and the OP sounded like this.

 

[firebirdparts]

I presume also this is a one and one half story building. It’s a very bad style of building to stop the wind blowing through it.

 

[flat350]

It's typical of many homes in the area you live in that we did when I was working still. The small slanted roof is just a detail that they add so the front of the home isn't a big flat wall. The space above the garage isn't really an attic, they build a second ceiling to try and create a somewhat conditioned space for the second floor mechanicals. Most of the ones we did the tin knocker would run a couple of 3" or 4" flex lines into it to keep it a little bit warm in the winter and it usually worked as long as there wasn't a lot of outside air transfer.