Cathedral ceilings are very popular in Alaska, both because of aesthetics and because of factors such as durability, cost, and logistics. Rafter-framed, wood-paneled cathedral ceilings lend themselves particularly well to smaller homes and to log homes.
However, wood-paneled cathedral ceilings can be especially vulnerable to air leakage. They can also be difficult and expensive to repair or replace: Unlike a truss-framed roof where repairs can often be mounted from within an attic space, accessing a problematic cathedral ceiling usually necessitates removing much of the roof system from either the inside or the outside.
In this video, we inspect a rafter-framed tongue and groove cathedral ceiling on a small 25-year-old log home in Fairbanks, Alaska (IECC Climate Zone 8). This home has a history of severe ice dams, and has already had extensive repairs done which failed to address the issue, presumably due to a lack of understanding of the causes. Here we diagnose the origins of the ice dam through interior and exterior visual inspections, augmented with an air leakage test and IR camera scanning. Along the way we offer insight into the conditions and construction choices that can lead to ice dams like this one.
The home is slated to have the shingles and sheathing removed in summer 2025 in order to effect improvements to its insulation, air sealing, and venting. We plan to follow up this diagnostic video with a video documenting and explaining these roof repairs as they take place.
The Cold Climate Housing Research Center has produced a number of videos related to cathedral ceilings. Two videos related to new construction are:
Cold Climate Building Techniques and Concepts: Building a cathedral roof https://youtu.be/mOK-D3rsomw?si=xMHMzSCq_vcjFUdH
Cold Climate Building Techniques and Concepts: Vapor retarder
https://youtu.be/R8RMR-e-LlE?si=sA2q6dSCzxu-rpTt
We also have three videos related to repairs and retrofits:
Cabin Energy Improvements Part 3: Roof https://youtu.be/zEU4nW3v6i0?si=tHxwCDEaUrf2OFHP
Replacing a Ceiling Vapor Retarder https://youtu.be/yM_OK08QpCM?si=hAxAFcGcOP6wNL2d
Basic vapor retarder installation https://youtu.be/elEH6dDcm4o?si=-helr6fYRCpZsor5
We welcome questions and discussion in the comments and you can also reach us at info@cchrc.org.
CCHRC website: www.cchrc.org
CCHRC YouTube channel: @coldclimatehousing
Music: "Motivational inspiring music" by Alexander Blu from https://orangefreesounds.com/. The song is permitted for non-commercial use under license “Attribution-NonCommercial 4.0 International (CC BY-NC 4.0).”