Ice shield on entire house?

Randy,you said you could see a seconday roof underneith. There should not be heat generated, it should be a cold spot.Installing Grace 100 % could cause "back up" on a heated roof. Seeing that it is not, it shouldn't be a prblem. Yes i've installed ice and water shield 100% on decks of that pitch,as long as you vent it over kill. vent, vent, vent. to keep it a cold spot, you don't want heat.

There have been quite a few insurance adjusters going around giving home owners new roofs this Winter with leaky ice dams.

What they should really do is give them a credit to use for an insulation/ventilation pro to fix the problem.

Got tons of calls from home owners with roofs ranging from 3 months to 2 years old with proper ice and water shield with leaks from ice dams this Winter.

Just so you know and keep this in mind when trouble shooting a new roof to a customer with ice dam issues. No manufacturer of ice and water shield will warrant against water back up on an ice dam causing a leak. They'll warrant wind driven rain and even ice but not standing water on an ice dam, plain and simple.

This Winter the biggest "puddle" I saw on a roof was about 6 inches deep. It was on a 3/12 with full ice and water. Yes, it found a way in!!

The drawback to putting ice shield over felt is the felt allows movement that could potentially enlarge the penetration holes of nails to a point the ice shield couldn't seal it. You would lose any warranty of the ice shield in doing so. That said, I have used it over felt many times on repairs, and never had a problem. If you can put it down, can avoid walking on it and be pretty confident the homeowner won't have traffic on the roof, you could probably get away with it. It'd be a calculated risk.

This building has good ventilation but insulation is a little low. This building don't usually ice up from snow.....it is just this year we had an ice storm followed by zero temps.....I bet 25% or more of homes had leaks.

What do you guys think about putting ice shield over felt paper? That way if it is ever torn off and replaced, the ice shield will come up and leave decking undamaged.

My main concern was sealing deck that tight.....but it sounds like others do it. I just don't want to leave any chance of another ice dam leak, it makes me look bad.

Thanks guys!

Metal roofs get full Ice and Water (high temp) quite often around here. I use it on tile as an underlayment on everything 4/12 and under and never had a problem. But I'm in an area that ice damming is rare.

If that`s your only alternative,open the soffits as much as possible,full ridge vent, when you replace again,expect to change a lot of decking/plywood

Insulating the space would be the right thing to do, no heat loss=no ice

I'll go with Copperman on that. You can't totally seal the roof. It will only create other problems. As you said this was out of the norm. Seal in your eaves & rakes if you feel the need. Don't seal the roof, just like the rest of us, we need to breathe. PC

What Copper said. Install a vent at the bottom into the area between the roofs, and then install a ridgevent at the top. Use the AirVentII ridge vent. that will stop the buildup.

You should look at correcting the insulation and vent problems first. I'm against ice & water shield on the whole deck. Would be a real dog to replace.