Wood insert creating ice dams

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nmaho

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Jan 15, 2014
126
Ma
Lived in this house for 22 years now and never had a problem with water int the winter. Had insert installed last year but did not burn for long did not have to much dry wood. This year we have basically burned every day this winter after 400 during the week and all day on the weekends. I know snow has been bad this year in the northeast and very cold. I'm thinking the only thing different is the high heat rising through the ceilings or chimney on out side wall going up through the garage raising the temps in attic causing problem??
 
What is your attic ventilation setup?
 
Is there a leak somewhere from ice damning?
 
I am shutting the stove down while there is snow on the roof. I know damage has been done already but I'll get some channels on roof this week and hope for a slow thaw.
 
If the vent at the peak is buried under snow is isn't venting.
 
Take a walk in your attic if you can and see if you feel the vents working. Lots of houses around us have massive ice dams this year. It snowed a lot and stayed very cold which is a recipe for ice dams.
 
I hate seeing the ice dams on my home and they are bad this year. I'm sure it's a function of the type of weather we have had but still it sucks. You shouldn't have leaks though you should have shielding below the roofing in your valley's and across the bottom.
 
Going in the attic is a good suggestion. Check and see if you can spot the leak(s) while you're up there.
High snow can cause leaks when you never had leaks before.
 
Roof is 22 years old also it could be tired and need replacing, who knows what they put under roof 22 years ago?
 
Ice and Water Shield was around 25 years ago but many roofers stuck with tar paper. I helped a few contractors doing their own roofs and we used one row of ice and water shield on the edge of the roof and one down any valleys. When I did my garage 20 years ago the supplier sent me a cheap substitute and I was in rush so I used one course of it on the bottom edge.

A lot of new homes 20 years ago had corruvent or vent a ridge installed instead of gable end vents. Some folks who don't understand how roof vents work think you cant use both but a ridge vent is useless covered with snow when you need it the most. If you block up the ridge vent the attic will be warmer than the soffits and ice dams will form.

I expect some folks are having issues where they added another layer of insulation in the attic and didn't leave space for soffit ventilation or extended the proper vents. Great year to open up a roofing business as there will be plenty of work in the spring.
 
Same issues here.

I can't go up into the attic because there is no attic over the leaks.

Keep cleaning it off, and knocking off the ice.
 
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It isn't just having the right ventilation,, you also need to make sure you air seal your ceiling. If your inside ceiling isn't sealed all the nice warm air your insert is putting out will rise and go right through the ceiling into the attic.
 
I'm having the same issue. Roof is 20 years old, maybe we'll have to replace it sooner than we thought. I'm trying the salt in panty hose trick but it's going to be so cold this week not sure it will do anything.
 
I noticed ice dams after installing my insert 4 years ago as well as we previously kept the house at 60 degrees because I hated to see the oil truck. I re insulated the attic and haven't had a problem since. My wife and I were driving around today bored during the snow storm and it seemed like 9 out of 10 houses had ice dams so don't feel to bad.
 
A lot of new homes 20 years ago had corruvent or vent a ridge installed instead of gable end vents. Some folks who don't understand how roof vents work think you cant use both but a ridge vent is useless covered with snow when you need it the most. If you block up the ridge vent the attic will be warmer than the soffits and ice dams will form.

Yeah right. When the first ice dams this built in 1985 house had that ripped the gutters off it in 2010 it had soffit and gable vents. I wish you luck with that. I had the roof ripped off of the sucker and a ridge vent installed.

Too many studies out there prove that gable and ridge together "short circuit" the venting. And that rising heat clears the ridge vent.
 
We deal with this all the time out here with our large snow loads. The short term answer is shovel off the affected area and put a bit of salt up there but keep in mind lawns and gardens below as well as stove pipe location. Getting the snow off and freeing up the backed up water behind the wall of ice is the key. It may not appear like there's lots of water, may only be wet looking ice but thats where you start. It can be alarming when its coming in to your house but once you free the path it will stop. Good suggestions on going in to the attic, this way you can pin point the problem. If youre going to do any chipping be very careful you dont damage your roof. Treat it more like a dinosaur excavation and you will be fine.
 
We've had an unprecedented amount of snow in a small time frame, couple that with the higher February sun and this year is going to be bad for ice dams. I know some people put calcium chloride in panty hose and toss them every few feet on the eaves, not sure if it works but I see a lot of people doing it. In the future just get a roof rake and clear the bottom foot or so of your roof after every storm so it doesn't build up..
 
An ice dam works like a typical icicle. Even if there is nothing near the edge of the roof the slight melting due to a warm roof reaches the part near the edge where there is no heat and it freezes again. Over time the runoff becomes the ice dam. If you have a few degrees below freezing the slight heating in the attic can start the whole thing happening. If you only have felt near the edge of the roof water can back up under your shingles and into your attic.
 
Yeah right. When the first ice dams this built in 1985 house had that ripped the gutters off it in 2010 it had soffit and gable vents. I wish you luck with that. I had the roof ripped off of the sucker and a ridge vent installed.

Too many studies out there prove that gable and ridge together "short circuit" the venting. And that rising heat clears the ridge vent.

Lots of contractors know how to build soffits and some even put in enough vents but unfortunately the folks who put in insulation tend to forget to install "proper vents " under the roof deck and plug the air flow with insulation. I expect that you got lucky the second time around and the contractor got it right so ridge vent or gable vent it still wouldn't dam. I had a home in Northeast Wisconsin I bought in the fall, I soon learned from the neighbors that the couple who owned it had constant ice damming issues. During the inspection I has noticed insulation stuffed in space between the top of the wall and soffits. Soon after I moved in it snowed and I saw ice dams. I spent a couple of weekends with a pole and hook pulling out the insulation and it was quite noticeable how the ice damming went away. I then installed proper vents and put another layer of insulation in the attic pushed right up against the proper vents. I didn't have any issues the rest of the winter.

I have two structures currently one with gable vents, one without, both have vent a ridge. I would tend to agree that with a couple of inches of snow and sunny day, the ridge vents do clear. Put in 24" of snow and neither one ever melts out on either roof.

It all comes down to extremes. The areas in Mass and southern NH don't typically get sustained deep snow while my area in northern NH does. Therefore the construction details that impact ice damming aren't as important in the south but when there is unusual winter they suffer. The design snow load (which is proportional to the potential snow depth) for Mass used to be as low as 30 psf (more recently upped to 55 psf), the town about 800 feet west of my house, Randolph NH has a 110 PSF ground snow load while my town has a paltry 100 PSF load. I do have many years with 3 plus feet on my roof on 3.5/12 pitch roof (fairly shallow for my area) and have never had a trace of ice damming in 25 years. If its gets up over 4' I usually shovel it. The majority of the homes in my neighborhood are the same as the local contractors eventually had a clue or folks like myself who DIY make sure that its done right and for the vast majority that's gable end vents with optional vent a ridge.

The only higher snows loads in NH than Randolph are in unorganized townships in the heart of the mountains that have few residential buildings they peak out at 115 PSF Just south of me is Pinkhams Grant (115 psf) on the side of Mt Washington, its on a major highway but they get lots of snow, this article about the 1968 to 1969 snow years is quite interesting http://www.ohcroo.com/winter_of_1969.cfm They have gable vents on their buildings. There is a reference in the article about roofs collapsing on commercial buildings in Berlin NH which is north of Pinkhams Grant in 1969 . Pitched roofs became popular on many of the replacement buildings. A local contractor resorted to building "periscope" vents vent.JPG, these about 12x12 inch wide at the base 4 to 6 feet high tapering outwards slightly with a cupola roof on top. They are mounted on the ridgepole and stick up in the air with louvers on all four sides. They look darn peculiar, I thought they were some sort of purple martin bird house and it took me awhile to find someone who knew the history and they were built in direct response to the winter of 69 so the attic would always vent no matter what the snow depth. Most of the buildings with that detail are getting old and have been torn down but there are still some around.

I expect the response in Mass after the winter is over is stick with what normally works and the low bid gets the job so many of the details to prevent the 1 in 20 year events don't get installed. Most folks don't plan to stay in their home for many more years so they roll the dice and hope they aren't there for the next snowy winter. Roof cables work but the UV deteriorates them so eventually they short out and are removed. One detail I haven't seen for years in my area are wide metal flashings that extend up from the base of the roof for 3 or 4 feet. My understanding is the ice and water shield has replaced it as it goes down quicker and doesn't require a skilled tradesman. I do occasionally see valleys flashed that way.
 
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My parents have had the cable in there gutters and along the roof eave for at least 10 years now, no issues with deterioration or shorts as of yet. They do work, they won't keep all the ice from forming, but they do keep a path for the melt to run down into the gutter, along the gutter, and down the spout into each drain pipe in the ground.
 
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Same thing is happening to me. Around my chimney the snow melts and freezes at the gutter. More water and larger icicles.We have had 4 feet of snow here in three weeks. Today I used my roof rake for 5 hours clearing the roof. We bought a Napoleon 1402 last year. Winter in New England you deal with things and don't groan about it.
DSCF1271.JPG
 
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There ya have it, just imaging how much is backing up under those shingles & or down the back of the fascia board.
This is where Ice and water shield should be installed on entire roof deck, or at minimal the last 3-6 feet, wrapped down over the fascia board or capping on the fascia board, then sandwiched in place with the gutter.
Won't stop the gutter from becoming a tube of ice, or those cool icicles, but will keep any water from getting to the roof deck or inside.
Man I just want to pull one of those off and eat it like when I was a kid. Cool pic!
 
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I can remember as a kid one year we had icicles that reached the ground, from the second story.!!! We weren't allowed near them, though it was tempting to throw snowballs at them. No woodstove, just an old house with a oil boiler.
 
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