Ice And Water Shield Roof Code

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.

Ice and water shield roof code.

Ice and water protector sometimes also referred to as ice and water shield is a waterproof roof underlayment membrane developed to protect vulnerable areas on a roof from ice and water damage. On roofs with slope equal to or greater than eight units vertical in 12 units horizontal 67 percent slope 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. The eaves flashing shall be installed from the end of the deck to a minimum of 24 inches up the slope. This code implies that ice and water shield eaves flashing is required for installation on all heated steep slope structures exception is unheated structures in colder climates.

The code requires that underlayment of one layer of non perforated type 15 felt lapped two inches horizontally and four inches vertically to shed water. In addition an ice barrier that consists of at least two layers of underlayment cemented together or of a self adhering polymer modified minimum vent area. 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 at least 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 at least 24 inches 610 mm inside the exterior wall line of the building. Many local building codes require ice and water shield and national building code states ice and water shield must start at the roofs eave edge and extend 2 ft inside heated wall space of a structure.

Ice and water protectors sometimes called ice and snow shields in cold climates are made with polymer modified bitumen. If an ice dam occurs on your roof and water backs up under the shingles it will seep down into your home through the nail holes holding the shingles. Roofing ice and water shield is a critically component to any new roofing system especially in cold weather climates. Ice and water shield.

The minimum net free ventilating. Building codes questions ray boosinger phone. Eaves flashing is required to prevent ice formation at the eaves and gutter to back up beneath the roof covering. Detached accessory structures not containing conditioned floor area.