Soffit ventilation dilemma

[Paul-M]

Hi,

I want to provide soffit ventilation to work with a new roof ridge vent (poorly functioning gable vents will be closed off).

The narrow soffits are already covered in vinyl and it feels like plywood under the vinyl.

1) One thought ( as proposed by a roofer) is to remove the vinyl, cut the appropriate size openings in the plywood, and replace the solid vinyl with perforated vinyl. My concern, because of the narrowness of the soffit, is how to remove/replace without disturbing the existing fascia trim or gutters. (see photo)

2) Another thought is just cut some sections of the vinyl soffit material, drill vent holes and 'somehow' overlay just the removed sections

with matching perforated vinyl. Does this seem at all reasonable?

3) Your recommendations are appreciated.

Thanks, Paul-M in Ct.

 

[SandburRanch]

You are about to open a big can of worms. What evidence do you have the gable vents are functioning poorly ?
There are 150 year old houses still standing very well with nothing but gable vents and ridge vents weren't heard of.

If you've been told cold air will enter the soffits and hug the under side of the roof sheathing until it exits the ridge vents, those people know very little about the physical science of cold air.

 

[Paul-M]

Thanks SR for the quick reply. Here's the longer story behind my project. I'm in a house for 8 years and about to replace a 20 yr old roof.

An estimator discovered a mold issue inside the attic space of the addition that was put on to the house about 30 years ago. (To the right of garage in photo). That mold condition did not exist on the building inspection when I moved in. (And that section was unoccupied for some time before I moved in).

The gable vent now between the garage and the addition is still open, and there is a an open gable vent on the outside of the addition. I'm guessing the partial ridge vent was added with the roof 20 years ago. The ridge cutouts look to be undersize (only about 1/4"). There are baffled inside the attic, but I don't know if they're getting any air through the vinyl-covered soffits. The light in the attic photos is from flashlight, not from the outside.

Sorry if I misled you with the other picture. I don't really need to address the upper level attic on the main 60 year old house. I just wanted to show the narrow eaves.

 

[Paul-M]

One more data point. The siding was added in 2011 (2 years before I took ownership)

 

[SandburRanch]

Being 1 gable vent is in the garage ( if I'm understanding correctly ), that area of the house only has 1 functioning gable vent because the 1 in the garage has very little value by not being open to the elements.

As I see it, no mold being listed on an inspection prior to your purchase doesn't mean much, at least not to me unless that was on a check-off list.

 

[Paul-M]

I agree with little value for the 'inside' gable vent. It might even be contributing to the problem. So, I still think the proper solution is to close the gables and install proper soffit-to-ridge ventilation. IF that's correct, I'm back to 'how to vent the soffits. The ridge part is easy with the new roof going on.

 

[SandburRanch]

OP Quote:
My concern, because of the narrowness of the soffit, is how to remove/replace without disturbing the existing fascia trim or gutters.
_______________________________________________________________________________________
I'm not a carpenter or in construction of houses, but the carpenter's concern is always to provide himself with a nailing surface to fasten - this to that -. With your concern of removing the soffit material consider looking for fasteners of some kind and if none are visible that soffit material may have been simply laid in the 2 pieces of channel appearing pieces if it was flexible enough to bend some. We know an end product must have the LOOK whether it is very functional or not.

To the best of my knowledge the Fascia and Gutter is independent of the soffit. This link may provide some useful information on a typical Soffit, Fascia, Gutter construction. If there is plywood under the Vinyl soffit you could even find 4x12" vents under the Vinyl.

Framing Eaves and Rakes

John Carroll demystifies the steps needed to create a good overhang that protects the building and provides solid nailing for the finish materials.

www.jlconline.com

 

[Paul-M]

Good article, SR-
Your input, plus some other research I've been doing has convinced me to slow down on the soffit venting. Why? Because I discovered that the bathroom ceiling light/vent units vent into the attic space instead of through the roof. (Duh! How did I miss that?) Anyway, that will be corrected when the new roof goes on.
Thanks again...

 

[SandburRanch]

I suspect you've found the culprit.

We have a house with 2 baths with that fan configuration so on my schedule those 2 fans get disabled during the winter months when we need the moisture in the living quarters and the attic certainly does not need that moisture. In the warmer months when the daytime attic temperature sometimes reaches 120°F or more that moisture delivered to the attic isn't a problem.

 

[Paul-M]

Nice approach. I still plan to vent those baths to the roof while it's easy to do. As I explore, I've found another disturbing issue.

The latest 'finding' is that the bay for the non-opening kitchen skylight has a vent to the attic. Does this make any sense, other than to lose heat in the winter? I can't tell from this camera angle if the vent is covered by the insulation (but I will find out).

This one picture attempts to highlight all issues.

 

[SandburRanch]

I can't think a - vented - skylight to the attic could ever be worthwhile except possibly allowing kitchen heat to rise to the attic. We both know that's not a good plan for winter conditions. Your skylight bay does look well insulated though.

Speaking of skylights, I view those as being similar to the recreational boat. The 2 happiest days in my wife's and my life. The day it was installed and the day I had the roofers pitch it in the dumpster.