Attic Baffle Instal Advice
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Hello everyone.
Writing from Hastings Highlands, Ontario. Our zone is not on the map as we are in Canada but I’d say it’s closer to the 7A realm.
Working on a first time renovation project and trying to formulate a plan for our attic ventilation. Our home was built sometime between 1850-1870. It’s old but sturdy although it does come with many layers to uncover. We heard baffles are pretty important for our attic ventilation to prevent ice damming, minimize moisture problems and to increase the roof’s lifespan.
The home is a single gabled construction. The roof pitch is quite steep and the roof extends down a little over halfway on the second level (attaching a photo of the exterior for a better idea). We’ve brought it down to the studs in most areas as there was quite a bit of water damage. Half of the roof was replaced with steel on top of the old shingles and the first thing we did was to match that on the other side (also on top of the old shingles). The attic has a fairly decent layer of blown in cellulose covering it (approx. 7 inches) however the cellulose goes all the way up to the edges of the roof with no gap allowance. The home has a unique “double sheathing” type situation happening. There are boards that run the full interior perimeter. Between these boards and the actual sheathing are patches of old cellulose that have sank and compacted over time (this is present in the walls) and what looks to be blown in yellow fibreglass insulation (between the roof sheathing and the slanted ceiling on the second level). So that’s kind of laying the land for my question.
We wanted to install baffles but we knew it would be basically impossible to extract the yellow insulation from the attic. We decided to remove one of the horizontal interior boards on the slant so we could push the insulation from above and have it fall onto the floor below. When we removed the board what we found was instead of a nice air gap that went down to the soffits like we expected, a layer of concrete that in theory prevents any kind of airflow coming from the soffit and additionally any potential baffle from getting down there.
With all of that said – wondering should we remove the concrete so we can move forward with our baffle installation plan? Or should we scratch the original plan and do something else? Would love some advice here.
Attaching photos for reference of the situation. The very dark photo is from inside the attic showing the current insulation situation and a very old pole beam!
Thanks in advance and apologies if my info above isn’t 100% clear. Like I said, we are newbies in the home reno department.
Cordelia
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Replies
Hi Cordelia,
I noticed that your GBA post was posted twice... I am curious if you're having trouble posting your question and if you're getting en error? It looks a few people have posted multiple times and it is also showing the data in 1970.
Thanks