Purchased 70 yr old home (a little less than 1000 sq ft) in midwest 3 yrs ago, replaced leaky seamed vinyl gutters with seamless aluminum gutters two winters ago and added additional layer of attic insulation over new layer already installed by previous owner. Roof is approximately six y/o. First winter had ice dams, last summer put in soffit vents with inside air channels to direct air to roof vents.
Have gable vents and four "mushroom" roof vents.
I still have ice dams and now also have icicles hanging over the outside edge of gutters AND hanging between the gutters and eave. Does this sound like an insulation problem, incorrect gutter hang, both, of something else?

From what you describe, and if the insulation and ventilation were done properly, I would suspect the gutters. Most gutter installers haven't a clue about how to hang gutters.

It is important that the outside edge of the gutter lie below the projected slope of the roof. The flatter the slope, the greater this distance should be. For example, for a 4/12 roof slope, the distance should be an inch. For a slope of 10/12, the distance can be 1/4 inch. Slopes in between shoudl have distances also in between. This is primarily to allow snow to slide off the roof without pulling the gutters down with it.

However, even if the distance is wrong, it should not contribute to ice dams and icicles. When is the last time you cleaned your gutters? If the gutter or downspouts are clogged, the gutter will retain water, which will freeze, and then snow melt has nowhere to go but back up onto the roof, and ice dams and icicles will follow.

Thank you for the response, Richard. Much to
my boyfriend's annoyance, I watch the gutters
like a hawk and they get cleaned and hosed out at least 7-10 times during spring, summer and fall, the last time being after ALL the leaves and seeds are off the trees. I suspect incorrect gutter hang is at least contributing to the problem as I've noticed water splashing over the outer edge of the gutters during heavy rain.

Hmmm. How big is your roof? It's possible that your gutters are too small, but in the defense of the gutter people, I'd have to say that standard gutters are usually adequate for almost all residential roofs.

Hanging them too high or too low would not cause ice dams or icicles. Maybe thay are hung so that there is a space behind the gutter, so some water gets there and makes icicles. Or maybe your roof does not have a proper drip edge, which would allow water to run back up the slope under the roofing rather than drip into the gutter, and then drip down behind the gutter.

Maybe, but not likely, there is insufficient pitch on the gutter, allowing water to remain in it rather than run off quickly.

Sounds like the soffit vents are not big enough and the gutters are not properly placed on the fascia board. The reason for the ice is warm air is melting the snow and ice on the roof and allowing it to freeze again once its in the gutter or past the warmer attic areas. If the soffit vents are not installed correctly or not cut all the way through into the attic, (happens when vinyl soffits are installed and the contractor fails to cut away the old soffit to allow air flow) Ideally your attic should always be the same temp as the exterior of the house. If you have warm air getting into the attic because of open pull down stairs, or lots of pot lights this heat will cause the melting action which can cause your issue.
Is the Ice only forming in one area or is it all over the place? Front, back, right or left sides? What is in the areas that seem to be the worse that could be raising the temp in the attic in that location. Bath Vent perhaps? It is usually a very simple thing to correct.

I agree with the lack of ventilation getting into the attic space, OR leaking heated air getting up from the living spaces into the attic. As suggested, check the bath vents properly discharging to the outside, not into the attic space. Look for holes or uninsulated areas where air is passing from the home into the attic, or being blown out by disconnected heating ductwork or air returns........warm air is getting into the attic causing the moisture on the roof (rain, dew, snow) to melt and or ice up.
Sid Michigan

Good call Sidney. We do forensic investigations in problem buildings. Aside from the obvious bath/kitchen fans exhausting into the attic, less obvious leaks from the conditioned spaces into the attic seem to be one of the main causes of ice dams in the buildings we look at. I suggest this summer, when it's warm, hire someone who has a blower door to find and seal those leaks. A blower door is just a big fan that is used to pressurize the building. Leaks are found using chemical smoke. Not only will this likely solve the ice dam problem but also save some energy.

However, understand that by sealing the leaks to the attic you will be reducing the ventilation rate of the living area. This may not be a problem but possibly could "tip you over the edge" and cause condensation porlbems.
Good Luck

I recommend you install heat trace wire in the gutters and on the lower 2 to 3 feet of the roof. Use the heat trace whenever there is the threat of snow or ice buildup on the roof. I had this system in Connecticut and it saved the house.

The posts about heat leaking from the house into the attic are excellent, and I wish I'd thought of it first! Maybe that pressure test is something you could do to help find the problem.

The heat trace wire will work, no doubt, but I would try first to discover the cause of the problem and try to solve it. There are millions of houses that don't have heat wire and also don't have ice dams, and that kind of remedy is not a solution, it's a band-aid, even if it's a very good band-aid. If and when all else fails, you can always put up the heat wires. If you can find and eliminate the cause of your problem, you may not need the heat wires at all.

Thanks, everyone, for all suggestions. I have located a couple possible warm air leaks into the attic. Will see if fixing them helps.

1st time poster. Apologies if in wrong area, etc.

Similar ice dams/icicles issue, but in a new home.

Ours is a 3 year old home which the builder is quoting Tarion that their home warranty does not cover this situation.

We have a south facing home. This year, for the 1st time in the 3 winters of the house, we have severe ice build up in some but not all of the eve's / gutters on the south side of the house. The icicles are coming not only from the gutters but also (if I am using the term correctly) from the aluminum facia underneath the gutters.

And, on a vertical down 'gutter' (again apologies if not using the correct term) which takes the water from the horizontal gutters down to to earth, there is one vertical down 'gutter' which is in complete shade from the sun as it is on the west part of the hourse which is 3 feet from our neighbour's wall. It is completely frozen with ice on the outside and inside.


Any ideas on (A) possible builder / gutter installation contractor mistakes and (BO how would I a complete lay person on house building would be able to tell and (C) what do I do?

Many thanks,
Dan

Dan I would check with an lawyer familure with construction law in your state. Do not accept what the builder is saying and do not ever sign anything about this issue without council. While I do not know what part of the country you live in, NJ warranty would cover this type of problem if water is getting in the house. Some ice damming cannot be stopped but if water is entering most likely they failed to install a ice and water sheild under the shingles.

Thank you very much for your reply.

Would ice on the gutters cause the down spout from the gutter (to the pipe in the lawn which takes away the water from the gutters) to completely freeze and split along the seam of the downspout? I would think (again I am new to all this) that if there was ice buildup or an ice dam on the gutters it would prevent water from getting into the downspout, rather than causing the downspout to be completely filled with ice the entire way from the roof to the ground.

Is this not symptomatic of there being a problem with the pipe in the lawn into which the downspout enters?

Just curious.

Thanks, again.
Dan

If the back of the leader pipe that drains the water from the gutter to the ground has split open because of freezing water, the downspout is either plugged or the bottom where it discharges is crushed and water has not drained properly. I see this a lot when the home is in an area where there is a lot of trees, Even if the gutters are cleaned quite often the leader pipes are not. The installing contractor may have used screws to fasten the leader pipe together at the elbows and these screws catch leaves and other debris if they are to long. Rivets are better suited for this task. If your doing it yourself,and do not have a rivit gun use the shortest screws 1/4" to fasten the sections so they do not fall apart.