Roofing Ice Dam Membrane

When installing a new roof or replacing the old one consider adding a water repellent membrane such as ice and water shield underneath the shingles.

Roofing ice dam membrane.

The purpose of ice and water underlayment is to stop water from passing through the roof system into a home. A roofing membrane required by building codes in the united states installed under the roofing material helps prevent leakage from ice damming but has no effect on the formation of ice dams. Ice and water membrane is needed most to address ice damming issues during the winter. Tim healey ice protection membrane and the code.

Installed underneath your shingles it effectively waterproofs your roof decking preventing leaks from heavy rains and ice dams. Then install regular roofing underlayment tar paper over the top of the drip edge and over the ice barrier and continuing all the way up the roof. Assuring integrity of the roof s waterproofing prevents leaks and consequent damage. An ice and water membrane is a type of self sealing adhesive underlayment.

Ask this old house general contractor tom silva explains the best ways to keep your roof and gutters free from those dreaded ice dams. Ice can build up on a roof slope usually at the unheated area at the eaves forming an ice dam that prevents water from draining off the roof. In turn this water can creep up under the shingles causing a roof leak. The distance from the lower edge of the roof to the intersecting point of the slope and the plumb line is the minimum required height of the membrane.

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. Ice and water protectors sometimes called ice and snow shields in cold climates are made with polymer modified bitumen. See below for a shopp. An ice dam is a thick rim of ice that originates along the edges of a roof when snow melts and then refreezes.

To set the height of the ice protection membrane according to the code measure 24 inches from the exterior wall and plumb up to the roof plane.