Have you just had your roof replaced and still have ice dam leaks?
Was the roofing removed to the wood decking?
Lots of ice and water shield installed?
New drip edge flashing, shingle under layment and new shingles installed?
Maybe even new windows as extra protection.
You could have done all these preventative measures and still be getting ice dam leaks.
The problem is that many roofing installers are installing the ice and water shield wrong. And part of that problem is that some manufacturers are recommending poor installation procedures.
Some suggest installing, after removing the roofing to the decking, the drip edge or eave apron at the bottom edge of the roof followed by the ice shield, underlayment and shingles. This is where the problem starts.There is a gap where the gutter board meets the roof decking. And this gap is open under the drip edging.
Now, snow melting from the roof will run to the gutter and freeze. It then builds up into an ice dam growing up and under the shingles and drip edging backing water into the soffit or behind the siding. The ice and water shield does no good. It's above the drip edge.
The proper way to install ice and water shield is to install it to the roof decking first. Apply the first row on the roof decking with enough draped over the edge to run down the face of the gutter board and behind the gutter. Closing and sealing the gap between the roof and gutter. Then install the drip edge, felt and shingles, and finish by re installing the gutter.
Now, the water backing up from the gutter is blocked from getting into the soffit and behind the siding.
This will keep the ice dam backup from entering the structure, but it does nothing to remedy the cause of the ice dam.