For a low slope residential roof there are two main options.
Roof repair ice and water shield low pitch.
1 cover the entire surface with a self adhesive flashing membrane such as grace ice water shield there are many equivalent products.
In colder regions a good practice is to cover the first 3 feet 36 inches or 0 91 m of roof over heated space with ice and water protector.
Overhang and a 2 6 exterior wall.
All overhangs should also be covered.
Ice and water shield.
59 3 8 inches up the roof slope from the drip edge.
The minimum is typically 2 feet 24 inches or 0 60 m above the vertical projection of the inside of the exterior wall.
As far as grace ice and water i did use it under shingles on the low pitch patio roofs of a retirement community re roof project i did 10 years ago 1 1 2 on 12 pitch.
Self adhesive flashing membrane under the shingles prevents leakage on low slope roofs.
My photo of an asphalt roof installation in process shows that the contractor has installed a peel and stick waterproof ice and water shield type product along the roof eaves in a 36 wide strip.
So what s the harm if the ice barrier isn t applied far enough up the roof slope.
Looked just like vycor without the printing.
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.
It was about 36 bucks for a one square roll back then.
Then apply standard asphalt shingles over the membrane.
Roofing ice and water shield is a critically component to any new roofing system especially in cold weather climates.
During winters when there is a lot of snow and ice dams form higher up the roof slope water can pond up behind the dams and reach higher than 36.
12 pitch roof with a 12 in.