Ridge Venting and Soffit vents


#1

He might be right about the ventilation IF your space between the finished ceiling and roof deck is stuffed solid with insulation. If there is airflow, you should be able to accomodate with eave and ridge vents.

I have a finished attic, and I’ve had more than one roofer tell me that most likely in this case ridge venting and soffit venting will not help. Is this true? and how would i ever know whether the space above the ceiling is packed with insulation (I didn’t finish the attic). There are crawl spaces where I can directly access the roof deck.

The soffit venting is no small expense, but my understanding is that my Certainteed warranty will be void without proper ventilation. also, that ridge venting is not very effective without the soffit venting. should I just forgo each of these?

Any thoughts?


#2

There is no real way to know if there is an airspace, unless you remove some shingles and wood to inspect.

If there was insulation packed tight, then you need to have the firred up treatment done or use rafter vent baffles beneath the wood to create a space for air to flow.


#3

Each cavities in your attic should be deal as a seperate attic, it seam that you got a lower crawl space and after a cathedral ceiling which is pack with insulation and maybe another little space at the top.
Correct me if i’m wrong.

But in a situation like your the ventilation is somehow quite important, but to be honest with you, I would be more concern about you knee wall, making sure you got the proper vapor barrier + tuck tape and boxed in using an r5 rigid foam and spray all seam using a 2 spray foam kit so that way you really keep the heat inside. Weather stripping on all attic hatch door.

Keep in mind that if you have an air space you need ventilation. Just hope for you that the insulation in you cathedral ceiling is not fiberglass


#4

hey damrite…bout your sig line…certified and master elite are 2 different things with GAF :wink:


#5

The idea is to keep your temperature inside the attic as close as possible as the outside, or get 10 complete air refreshment per hour.
If you got lots of money, go for it and remove those board and spray foam all cathedrale cavities.
When you get your final invoice have somebody take a picture of your face and post it here.

It also depend how low you want to stay in this house

Here in Canada, our company did lots of research on insulation and air sealing in order to provide our customer with top notch roof.

I go in the attic on maybe 90% of my jobs and let me tell, insulation in like roofing 95% of companies become overnight specialist.

P.S
Marshall I told you I was from Toronto, I live here but i’m born in Rimouski Quebec, (Hockey city)(Crosby,Lecavalier,Brad Richard…ect) But I still got a house In quebec city near the ice hotel.
Check it out hoteldeglace.qc.ca/en/images/photos/index.en.php

I’m leaving for Cuba next monday, on my way back i’m
going to Quebec city for the last snowmobile trip, I’ll meet you there. lol