Ice and Water Shield
A self-adhering roofing membrane used in vulnerable areas to resist water intrusion from ice dams and wind-driven rain.
Applies to
Roofing · Roof replacement
Project example
A roof replacement plan may call for ice barrier at eaves, valleys, or other locations defined by the adopted code and local conditions.
Also called
Where this term shows up in permit work and how it affects the project
Material and installation details can affect inspection, warranty discussions, and the contractor's scope; local snow and climate rules matter.
If this term appears in a form, plan comment, or local ordinance, start with the building permit guide, compare it against the zoning permit guide, then use the permit guide directory to find the right local path.
Why ice and water shield matters in a permit file
Ice and water shield is a self-adhered underlayment used at eaves and other vulnerable roof locations to resist leaks caused by ice dams and wind-driven water. Required extent and acceptable materials depend on the adopted code, local climate criteria, roof geometry, and manufacturer installation.
Where it appears in the permit process
Roof-scope review
The contractor documents reroof area, slope, eaves, valleys, walls, penetrations, existing layers, deck condition, and ventilation.
Code and product selection
The adopted roofing provisions and product listing establish membrane type, width, laps, substrate, temperature, and required locations.
Deck preparation and installation
Damaged deck is corrected and the membrane is installed continuously at the required eaves and details before covering.
Roofing inspection
Where required, the AHJ verifies underlayment, deck, flashing, ventilation, and roof-covering conditions at the appropriate stage.
What you may need
- Roof permit scope and existing-layer information
- Roof plan or written detail identifying eaves, valleys, walls, and penetrations
- Membrane product data and installation instructions
- Deck replacement, flashing, ventilation, and roof-covering details
- Photographs or inspection access before the membrane is concealed when required
Where to get it or verify it
- Use the AHJ's adopted roofing code and local ice-barrier criteria.
- Use the membrane and roof-covering manufacturers for compatible products and installation conditions.
- Ask the inspector whether underlayment must remain visible or may be documented by staged photographs.
Common mistakes that create comments or delays
- Using a product that is not listed for the intended roof assembly
- Stopping the membrane at the exterior wall instead of the locally required interior projection
- Applying over wet, damaged, dirty, or incompatible substrate
- Covering all underlayment before a required inspection
What to do next
- Confirm the adopted ice-barrier requirement and all vulnerable roof areas.
- Coordinate deck repair, membrane, flashing, ventilation, and roof covering.
- Install within the product's substrate and weather limits.
- Document the concealed membrane before completing the roof.