Yeah hired a well known local company, it's warranted, I'll be giving him a call at some point. New shingles, striped to the boards, some boards were replaced. I had siding/gutters done after the roof, and they had to replace some fascia boards and repair some other hidden rot behind the gutters and I'm wondering if those guys compromised something. That will be great if i get into a "its their fault, no its their fault" situation. I had to use some, um persuasive actions, to get the siding guys to stick to the agreed upon contract, they weren't going to reproduce the period correct trim on the house, which was agreed to and written in the contract, because they said they under quoted me and they weren't going to make "AS MUCH as they originally thought"..their exact words... I'm pretty sure they will do anything possible to avoid coming back here..and honestly if i don't have to deal with another contractor, it'll be fine by me.
DO NOT PUT A FORCED AIR HEATER IN YOUR ATTIC AS IT ONLY WORSEN YOUR PROBLEM & CREATE MASSIVE CONDENSATION .You need to melt the ice outside to stop water being FORCED into the attic .
Your roofing contractor should of used a product ( Ice & water shield ) at the gutter line of your roof , the product is a sticky roll of 36 inch wide rubberized asphalt membrane ,it self seals all nail holes from the shingles & prevents ice & water dams , the ice & water shield is supposed to extend a full 36 inches into the attic space ,if you have extended eve's that extend farther than 8 inches past the outer wall the contractor is REQUIRED BY BUDING CODE TO INSTALL A 2nd row of the material on all eve edges .
Many scab contractors skip installing ice & water at the eve & in the valley as CODE requires because of the material cost , a cheap Home Depot brand costs about $80 a 33 ft long roll , high quality ice & water such as Grace ice & water costs as much as $ 180 for a 33 ft long x 36 inch wide roll , skipping using this material will save the contractor atleast $1,000 in material costs & the roof will never leak in a rain storm .
I'd bet money they either skipped installing any Ice & water shield membrane at the eve edge , or they didn't install the material where it extends a full 36 inches past the outer wall , if they had installed the material properly you would of never had any water forced into the building from the weight of the ice .
You need to melt the ice using a product called Roof Melt which is Calcium Chloride , it's safe to use on all asphalt shingles & won't void manufacturer warranty .
What's causing the water to run uphill & under the shingles is called Capillary Action where the weight of the ice is causing water to push against gravity , read here to understand why the water is going uphill .
http://en.m.wikipedia.org/wiki/File:Capillarity.svg
Get a ladder & start broadcasting the calcium chloride all over the iced roof areas & in the gutters , if possible disconnect your downspouts to increase water flow , after spreading out the calcium chloride over all iced areas water will start flowing fast , this is why you want to cover the entire gutter area with a thick layer of the product so the gutters melt out faster than the roof ,disconnecting all downspout will also help keep the freshly melted water from being forced further into the interior of the attic .
If you have a small plumbing torch melt the ice in the gutter outlets that will be exposed after disconnecting the downspouts , torch melting the ice blocking the outlet will relieve much of the capillary action caused by the fast melting ice from calcium chloride & it gives the water someplace to go , if you don't clear the gutter outlets & relieve pressure the new water has no choice but to flow up hill & in the attic.
You may have to spend several hundred dollars on calcium chloride & repeat the process several times in a day or 2 but it's the proper way to correct ice dams .
Your contractor may have fucked up your existing ventilation system on the roof as well , when replacing rotten fascia boards they coulda blocked any soffitt vent system , they could of not replaced existing can style square roof vents , shingled over the holes & relyied on an inferior ridge vent system to vent the attic space .
Most ice dams are caused by clogged gutters or improper ventilation of attics or plenum spaces , the thickness of attic insulation has nothing to do with your situation being that this is a new problem occurring directly after installing a new roof system .
Fyi I hold a Journeymans card in roofing & waterproofing & know wtf I'm talking about , whatever you do please don't add heat to the attic unless you want the entire roof deck's underside to be completely soaked with condensation .