[spcrooks]

Greetings,

I am new to the forum and the new owner of a largely unwinterized cottage. I have been reading myself in circles about roof ventilation/insulation, so maybe someone out there can point me to a thread that I missed or give me an idea of how to proceed.

I have a 20 x 11 exposed cathedral ceiling. As that I am getting ready for winter, I want to insulate it and properly vent it. I have the insulation and the 4 x8 sheets of bead board that will become the new ceiling. That leaves the venting issue.

I want to install static roof vents, but am unsure as to corresponding measures that must be taken.

I am under the impression that in order for them to be effective, there must be space between the insulation and roof itself to allow for air-flow.

Therefore, I am wondering if I need soffit vents to accompany the roof vents?

When it comes right down to it, I am unsure as to how it will work as a "system."

I would be grateful if anyone can point me in the right direction.

Thank you,

Sean

 

[CplDevilDog]

Yep, you have the correct idea.

You'll need a baffle system to keep the insulation batts from pressing tight to the underside of the roof sheathing. These will create a continuous airflow path from the soffit vents you are going to install to the ridge vent you are going to install.

There are many baffles on the market or you can hack together a cheapy version from cardboard boxes.

 

[spcrooks]

Thanks for the reply!

That being established, would it work to vent the soffit on the back of the cottage and then install the roof vents on the opposite side? or must each soffit vent have a corresponding roof vent on the same side of the roof?

Sean

 

[CplDevilDog]

Not sure what you mean.

Generally, your soffit venting would run the length of you eaves on both the front and back of the roof and the ridge vent would run the length of your ridge.

Fresh air enters at the soffit and as it heats it rises, carrying moisture and heat up through your baffles and out the ridge vent.

 

[CplDevilDog]

Ahh, OK. I see now that you are planning to use static roof vents as opposed to ridge vents.

Not recommended. You passive roof vent will only vent the particular rafter bay where it is installed. You need a ridge vent that runs the length of the ridge , thereby venting each rafter bay. Excepting the first and last where you'll have to start and end your run a foot short of your rake.