Examples of Poor Construction in Interior Alaska
Provided by Ilya Benesch, Cold Climate Housing Research Center (CCHRC)
Moisture in Attic.
In this example, you can see residue and freezing at the vents; indoor air is migrating through poorly sealed areas in the ceiling and into the attic.
Example of Ice Damming.
This roof is poorly insulated, poorly ventilated, has air leakage – or all 3. This happens to both old and new homes in the Interior if the construction detailing is poor.
Example of Poor Wall Insulation.
Frost on the wall is normal due to a sudden drop in outdoor temperatures, causing condensing to occur on the siding. What is not normal is all the spots that don’t have frost. These areas are either poorly insulated or missing insulation entirely. Note the areas around the rim joist area at the base of the wood siding- this is a highly visible example of poor insulation.
Example of Moisture Damage to Drywall.
Drywall removed from the ceiling of an addition to an existing home. New ceiling was poorly air sealed, which allowed moisture laden indoor air to migrate into the rafter bays. In addition, the new roof was built over the existing one and not vented. The moisture built up in the roof all winter as hoar frost, then turned to liquid water when it melted all at once when temperatures warmed up in spring. There was so much moisture, the drywall became saturated and started to collapse. These problems could have easily been avoided with a proper understanding of how to integrate a new roof into an old one when adding on a room.
Example of Roof Construction Deficiencies.
This IR Scan and above photo of the same interior walls show both moisture damage and localized heat loss due to construction deficiencies in the roof.
Example of Poor Attic Insulation.
This IR scan and above photo show air leakage around a bath fan ceiling penetration, an example of how moisture-laden air escapes into attic insulation due to unsealed holes around the ducting.
Example of Poor Chimney Insulation.
1) Chimney has no attic insulation shield and presents a fire hazard. Every chimney manufacturer has a strict minimum clearance to combustibles.
2) Chimney penetration is not air sealed and moisture laden indoor air is escaping into the attic. This is condensing in the insulation and on the underside of the roof sheathing, causing the saturated insulation to sink around the chimney.
Example of Attic Mold.
This is a picture of mold in an attic at one of the gable ends. This mold problem was caused by seasonal moisture build-up due to indoor air leakage into attic space.
Example of Poor Plumbing Seal & Installation.
This is a substandard plumbing vent install. No attempt was made to maintain an air seal around the vent penetration into the attic.
The Cold Climate Housing Research Center is an industry-based nonprofit based in Fairbanks, Alaska that develops and tests energy efficient building technologies for the north. The articles and videos included in this guide are part of its mission to promote healthy, sustainable, affordable housing in Alaska and beyond. Find more at cchrc.org.