Venting between kneewall attic and peak attic
Hi everyone –
First time here. I have a 1956 home that I am gradually upgrading various parts of.
I need advice/help with knee wall to peak attic ventilation.
I am in the process of deciding whether to seal/insulate the kneewall attics for storage/year-round temperature regulation. (Previous owners had a weird mixture of batts and poly, which I aim to rectify with polyiso, etc.)
The upstairs bedrooms are built inside the roof, with a peak attic above the bedroom ceiling, and knee wall attic spaces behind the bedroom walls. The peak attic is insulated above the bedroom ceiling, and has gable end vents at each end.
I read lots of guides and blogs, understanding that roof deck/sheathing needs to be ventilated from soffits at bottom edge of roof, preferable to ridge or gable end vents.
I bought a couple of pieces of polystyrene ventilation chute to try out between my rafters to help plan the job.
Problem is that when I went to feed the polystyrene venting chute between the rafters (over the top edge of the knee wall) to create an air pathway into the peak attic, I found that the gaps between rafters as they pass over the top edge of knee walls are all blocked with framing…due to the way this roof was built in 1956….(note: the channels between rafters are clear between roof-edge soffits and the blocked gaps at the top of the knee walls).
Has anyone encountered this before? I am very hesitant to mess around with the blocked paths between the rafters for fear of compromising structure.
If I keep the blocked pathways between rafters above knee walls:
a) how should I vent the roof deck & attic space if I decide to keep knee wall attic an ‘outside space’?
b) how should I vent the roof deck if I decide to seal and insulate knee wall attic spaces?
(from what I’ve read, I will not need to ventilate the attic spaces themselves, once sealed and made part off the house’s ‘inside’ space.)
Thanks in advance foe any advice you can give.
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