2021 edition
SECTION R905
REQUIREMENTS FOR ROOF COVERINGS
R905.1 Roof covering application.
. . . .
R905.1.2 Ice barriers. In areas where there has been a history of ice forming along the eaves causing a backup of water as designated in Table R301.2(1), an ice barrier shall be installed for asphalt shingles, metal roof shingles, mineral- surfaced roll roofing, slate and slate-type shingles, wood shingles and wood shakes. The ice barrier shall consist of not fewer than two layers of underlayment cemented together, or a self-adhering polymer-modified bitumen sheet shall be used in place of normal underlayment and extend from the lowest edges of all roof surfaces to a point not less than 24 inches (610 mm) inside the exterior wall line of the building. On roofs with slope equal to or greater than 8 units vertical in 12 units horizontal, the ice barrier shall also be applied not less than 36 inches (914 mm) measured along the roof slope from the eave edge of the building.
Exception: Detached accessory structures not containing conditioned floor area.
R905.2 Asphalt shingles. The installation of asphalt shingles shall comply with the provisions of this section.
. . . .
R905.2.7 Ice barrier. Where required, ice barriers shall comply with Section R905.1.2.
. . . .
(PLRB Note: footnote h. reads: “In accordance with Sections R905.1.2, R905.4.3.1, R905.5.3.1, R905.6.3.1, R905.7.3.1 and R905.8.3.1, where there has been a history of local damage from the effects of ice damming, the jurisdiction shall fill in this part of the table with “YES.” Otherwise, the jurisdiction shall fill in this part of the table with “NO.””)
2018 edition
SECTION R905
REQUIREMENTS FOR ROOF COVERINGS
R905.1 Roof covering application.
. . . .
R905.1.2 Ice barriers. In areas where there has been a history of ice forming along the eaves causing a backup of water as designated in Table R301.2(1), an ice barrier shall be installed for asphalt shingles, metal roof shingles, mineral- surfaced roll roofing, slate and slate-type shingles, wood shingles and wood shakes. The ice barrier shall consist of not fewer than two layers of underlayment cemented together, or a self-adhering polymer-modified bitumen sheet shall be used in place of normal underlayment and extend from the lowest edges of all roof surfaces to a point not less than 24 inches (610 mm) inside the exterior wall line of the building. On roofs with slope equal to or greater than 8 units vertical in 12 units horizontal, the ice barrier shall also be applied not less than 36 inches (914 mm) measured along the roof slope from the eave edge of the building.
Exception: Detached accessory structures not containing conditioned floor area.
R905.2 Asphalt shingles. The installation of asphalt shingles shall comply with the provisions of this section.
. . . .
R905.2.7 Ice barrier. Where required, ice barriers shall comply with Section R905.1.2.
. . . .
(PLRB Note: footnote h. reads: “In accordance with Sections R905.1.2, R905.4.3.1, R905.5.3.1, R905.6.3.1, R905.7.3.1 and R905.8.3.1, where there has been a history of local damage from the effects of ice damming, the jurisdiction shall fill in this part of the table with “YES.” Otherwise, the jurisdiction shall fill in this part of the table with “NO.””)
2015 edition
SECTION R905
REQUIREMENTS FOR ROOF COVERINGS
R905.1 Roof covering application.
. . . .
R905.1.2 Ice barriers. In areas where there has been a history of ice forming along the eaves causing a backup of water as designated in Table R301.2(1), an ice barrier shall be installed for asphalt shingles, metal roof shingles, mineral- surfaced roll roofing, slate and slate-type shingles, wood shingles and wood shakes. The ice barrier shall consist of not fewer than two layers of underlayment cemented together, or a self-adhering polymer-modified bitumen sheet shall be used in place of normal underlayment and extend from the lowest edges of all roof surfaces to a point not less than 24 inches (610 mm) inside the exterior wall line of the building. On roofs with slope equal to or greater than 8 units vertical in 12 units horizontal, the ice barrier shall also be applied not less than 36 inches (914 mm) measured along the roof slope from the eave edge of the building.
Exception: Detached accessory structures not containing conditioned floor area.
R905.2 Asphalt shingles. The installation of asphalt shingles shall comply with the provisions of this section.
. . . .
R905.2.7 Ice barrier. Where required, ice barriers shall comply with Section R905.1.2.
. . . .
(PLRB Note: footnote h. reads: “In accordance with Sections R905.1.2, R905.4.3.1, R905.5.3.1, R905.6.3.1, R905.7.3.1 and R905.8.3.1, where there has been a history of local damage from the effects of ice damming, the jurisdiction shall fill in this part of the table with “YES.” Otherwise, the jurisdiction shall fill in this part of the table with “NO.””)
2012 edition
SECTION R905
REQUIREMENTS FOR ROOF COVERINGS
. . . .
R905.2 Asphalt shingles.
. . . .
R905.2.7 Underlayment application.
. . . .
R905.2.7.1 Ice barrier. In areas where there has been a history of ice forming along the eaves causing a backup of water as designated in Table R301.2(1), an ice barrier that consists of a least two layers of underlayment cemented together or of a self-adhering polymer modified bitumen sheet, shall be used in lieu of normal underlayment and extend from the lowest edges of all roof surfaces to a point at least 24 inches (610 mm) inside the exterior wall line of the building.
Exception: Detached accessory structures that contain no conditioned floor area.
. . . . .
(PLRB Note: footnote h. reads: “In accordance with Sections R905.2.7.1, R905.4.3.1, R905.5.3.1, R905.6.3.1, R905.7.3.1 and R905.8.3.1, where there has been a history of local damage from the effects of ice damming, the jurisdiction shall fill in this part of the table with “YES.” Otherwise, the jurisdiction shall fill in this part of the table with “NO.””)
2009 edition
SECTION R905
REQUIREMENTS FOR ROOF COVERINGS
. . . .
R905.2 Asphalt shingles.
. . . .
R905.2.7 Underlayment application.
. . . .
R905.2.7.1 Ice barrier. In areas where there has been a history of ice forming along the eaves causing a backup of water as designated in Table R301.2(1), an ice barrier that consists of a least two layers of underlayment cemented together or of a self-adhering polymer modified bitumen sheet, shall be used in lieu of normal underlayment and extend from the lowest edges of all roof surfaces to a point at least 24 inches (610 mm) inside the exterior wall line of the building.
Exception: Detached accessory structures that contain no conditioned floor area.
. . . . .
(PLRB Note: footnote h. reads: “In accordance with Sections R905.2.7.1, R905.4.3.1, R905.5.3.1, R905.6.3.1, R905.7.3.1 and R905.8.3.1, where there has been a history of local damage from the effects of ice damming, the jurisdiction shall fill in this part of the table with “YES.” Otherwise, the jurisdiction shall fill in this part of the table with “NO.””)
2006 edition
SECTION R905
REQUIREMENTS FOR ROOF COVERINGS
. . . .
R905.2 Asphalt shingles.
. . . .
R905.2.7 Underlayment application.
. . . .
R905.2.7.1 Ice barrier. In areas where there has been a history of ice forming along the eaves causing a backup of water as designated in Table R301.2(1), an ice barrier that consists of a least two layers of underlayment cemented together or of a self-adhering polymer modified bitumen sheet, shall be used in lieu of normal underlayment and extend from the lowest edges of all roof surfaces to a point at least 24 inches (610 mm) inside the exterior wall line of the building.
Exception: Detached accessory structures that contain no conditioned floor area.
. . . . .
(PLRB Note: footnote h. reads: “In accordance with Sections R905.2.7.1, R905.4.3.1, R905.5.3.1, R905.6.3.1, R905.7.3.1 and R905.8.3.1, where there has been a history of local damage from the effects of ice damming, the jurisdiction shall fill in this part of the table with “YES.” Otherwise, the jurisdiction shall fill in this part of the table with “NO.””)
2003 edition
SECTION R905
REQUIREMENTS FOR ROOF COVERINGS
. . . .
R905.2 Asphalt shingles. The installation of asphalt shingles shall comply with the provisions of this section.
. . . .
R905.2.7.1 Ice protection. In areas where the average daily temperature in January is 25F (-4C) or less or when TableR301.2(1) criteria so designates, an ice barrier that consists of a least two layers of underlayment cemented together or of a self-adhering polymer modified bitumen sheet, shall be used in lieu of normal underlayment and extend from the eave’s edge to a point at least 24 inches (610 mm) inside the exterior wall line of the building.
Exception: Detached accessory structures that contain no conditioned floor area.
. . . .
2000 edition
SECTION R905
!REQUIREMENTS FOR ROOF COVERINGS
. . . .
R905.2 Asphant shingles. The installation of asphalt shinglesshall comply with the provisions of this section.
. . . .
R905.2.7.1 Ice protection. In areas where the average daily temperature in January is 25°F ( -4°C) or less, an ice barrier that consists of a least two layers of underlayment cemented together or of a self-adhering polymer modified bitumen sheet, shall be used in lieu of normal underlayment and extend from the eave’s edge to a point at least 24 inches ( 610 mm) inside the exterior wall line of the building.
