Roof & Gutter Heat Cables ?? OT

[JoeLee]

I never paid much attention to these so I'm not too well educated on them. There are too many different types and brands out there and it's difficult to make a uneducated choice.
I called a couple companies only to find that the people I was talking to must have been in Bombay or some place similar as I had to struggle just to understand what they were saying and when they tried to answer my question it seemed that they were reading something off a cheat sheet that matched what was shown on their web site. So.......... as usual I find myself here where I can get first hand reliable and accurate information from people that have had real experience with these.

I've heard some people say they are worthless, or shorted out etc. Some say they work great.

Aside from what you zig-zag along the roof line and how far up you go probably depends of how much over hang you have. Also I imagine you have to run a separate wire along the inside of the gutter to melt a channel for the water to flow to the nearest downspout.

At first I was under the assumption I could buy like a 1000 ft. roll and run it continuous around the perimeter of my house, but wasn't sure how the power distribution would work with varying lengths.

So far I have found that most of these come in pre-made lengths of like 60 ft. Not sure if that is 60 ft. of wire or weather it means that it covers 60 linear ft. of roof line.
It looks like the pre-made lengths are made because of wattage related issues and current draw. Someone told me that a 20 amp 110v circuit would handle two 60 ft. runs without tripping a breaker.

So, anyone out there with first hand experience with any of these or can recommend a certain mfg.

JL...............

[RMinMN]

I never paid much attention to these so I'm not too well educated on them. There are too many different types and brands out there and it's difficult to make a uneducated choice.
I called a couple companies only to find that the people I was talking to must have been in Bombay or some place similar as I had to struggle just to understand what they were saying and when they tried to answer my question it seemed that they were reading something off a cheat sheet that matched what was shown on their web site. So.......... as usual I find myself here where I can get first hand reliable and accurate information from people that have had real experience with these.

I've heard some people say they are worthless, or shorted out etc. Some say they work great.

Aside from what you zig-zag along the roof line and how far up you go probably depends of how much over hang you have. Also I imagine you have to run a separate wire along the inside of the gutter to melt a channel for the water to flow to the nearest downspout.

At first I was under the assumption I could buy like a 1000 ft. roll and run it continuous around the perimeter of my house, but wasn't sure how the power distribution would work with varying lengths.

So far I have found that most of these come in pre-made lengths of like 60 ft. Not sure if that is 60 ft. of wire or weather it means that it covers 60 linear ft. of roof line.
It looks like the pre-made lengths are made because of wattage related issues and current draw. Someone told me that a 20 amp 110v circuit would handle two 60 ft. runs without tripping a breaker.

So, anyone out there with first hand experience with any of these or can recommend a certain mfg.

JL...............

The purpose of these is to keep water from backing up behind the ice dam and seeping under the shingles which would ruin the wall. You don't need to worry about the downspouts, just let the water drip off the gutter if it is frozen. The 60 feet lets most people zigzag the wire along the roof edge. Most people do not have a 60 foot long eave without interruptions.

[thin-woodsman]

I removed the snowmelt wire that was on the roof when I bought the place. Once the temps got into the negative (F), the wire couldn't keep up with the ice that formed from its own action - it just made things worse.

I couple of years ago, I had a long metal melt panel installed at the eaves - basically a heated roof skirt. Here is an example : https://www.heattracespecialists.com...s/eave-systems
Note that this is an arbitrary example from a quick search; the panel was installed by a builder in town. I can find out what he used, if you're curious. No problems with ice since the panel was installed.

[JoeLee]

The purpose of these is to keep water from backing up behind the ice dam and seeping under the shingles which would ruin the wall. You don't need to worry about the downspouts, just let the water drip off the gutter if it is frozen. The 60 feet lets most people zigzag the wire along the roof edge. Most people do not have a 60 foot long eave without interruptions.

that's another design issue. There are a lot of people that do have more than 60 ft. of roof line. Especially if you have to go up and down a couple valleys. Then that 60' doesn't go very far.

JL.............

[JoeLee]

I removed the snowmelt wire that was on the roof when I bought the place. Once the temps got into the negative (F), the wire couldn't keep up with the ice that formed from its own action - it just made things worse.

I couple of years ago, I had a long metal melt panel installed at the eaves - basically a heated roof skirt. Here is an example : https://www.heattracespecialists.com...s/eave-systems
Note that this is an arbitrary example from a quick search; the panel was installed by a builder in town. I can find out what he used, if you're curious. No problems with ice since the panel was installed.

I understand where that can be a problem. When the temps get that cold and the snow stops melting there is no need to run them, nothing melting, nothing backing up.
You pretty much have to play it by ear from past experience when to plug them in and when not to use them. that in itself can be a PIA.
I've found some that have sensors or thermostats built in but I don't know how reliable that is. Too many unknowns with all this and every installation is different.

Never saw the heated panels shown in the link. I'll bet that is costly ! and an ice dam could still form behind it's melting point. What if the element burns out ? how do you find out where the break is? I would hate to start tearing up shingles to find it ore replace it.

I have usually gone up on the roof and shoveled the snow off the edge clearing it back about 3'. Sometimes that solves the problem and sometimes it doesn't. What happened this time is an ice dam formed right behind where I stopped shoveling. So now I have two dams. I was thinking of hooking the garden hose up to the hot water tank and melting the ice in the gutters in the problem areas and then hitting the edge of the roof line.

When I had the new roof put on a couple years ago the roofer who did a great job did two rows of the ice and water strip. I told him I didn't like the idea of that and he should stick with one row, 3 ft. as opposed to 6 ft because if the water is going to back up it's going to back up until it finds a place to drip.
With three feet of ice and water any back up usually resulted in the water running down the outside wall of the house 6 ft of strip put it well beyond the inside wall. So now I'm pressed to find another solution.
Another thing is the ridge vents, don't like them either. When I was up on the roof I noticed all the snow that was melted around them from any warm air in the attic escaping. That just creates snow melting at the peak and running down till it freezes up crating another dam.

JL..................

[kendall]

Normally you cover the roof to past where the roof/attic insulation ends, typically 3 to 4 feet is good enough. The heat cable itself can be purchased in rolls and cut to length, Ensure that you get heat cable not heat tape. The ends (plug and terminator) are reasonably priced).
Cable is round and internally regulated so it can cross if needed, tape is flat and HAS to be pressed against a heat conductive surface or it will burn out.

What most people do around here is run metal up 3 feet from the edge to let the ice/snow slide off, use snow guards over doors and walkways so you don't get ice or snow dropping on you.

Edit for a type example:

https://www.briskheat.com/products/h...ing-cable.html

If you have gutters, lay some heat cable in the bottom, then drop a length down the drain pipes. If you have valleys, lay cable in the bottom of them as well.
If you have boxed eaves, plumb a heat vent into them.

[old mart]

Save the planet by heating your roof. Why can't people just build houses with steep enough roofs so that the snow just slides off?

[rdfeil]

Do a google search for "outdoor industrial heat cable". You will find several manufacturers. I will not recommend specifics, but I have been around several different ones and they all worked well. You can buy fixed lengths or bulk cable and end kits. By my calculations you can easily power 360 feet of 5 watt per foot cable with a 20 amp 120 volt circuit with a 25% safety margin. One thing... the industrial cables are very well made and last a long time, but they are quite expensive!!

[RMinMN]

that's another design issue. There are a lot of people that do have more than 60 ft. of roof line. Especially if you have to go up and down a couple valleys. Then that 60' doesn't go very far.

JL.............

Valleys are interruptions. You do a run along the eaves only, not up the valley.

[RMinMN]

Save the planet by heating your roof. Why can't people just build houses with steep enough roofs so that the snow just slides off?

I have a gambrel roof with the steep part nearly vertical and with metal roofing. Snow still sticks to that until it gets a warm day. Do not be near the sides of the house when it finally decides to slide off.

[Mike279]

Thirty plus years ago I made my roof a cold roof by fully ventilating the eves, installing insulating channels and then putting a ridge vent at the top. Then I fully insulated the attic space as best I could. I never get an ice dam. That is the best way hands down, something your roofer has no interest in telling you. You need to fully vent your soffit so the intake air is outside temperature. That way any heat loss from the house goes out the ridge. When outside temps rise the snow melts evenly and cannot form a dam. I have had up to 4 ft of snow on the roof and in those rare instances, I prefer to lessen the snow load by removing some. I can find some ice like pellets on the shingle area but it's evenly distributed and never any dam like areas.

[thin-woodsman]

Never saw the heated panels shown in the link. I'll bet that is costly ! and an ice dam could still form behind it's melting point. What if the element burns out ? how do you find out where the break is? I would hate to start tearing up shingles to find it ore replace it.

About $150 a foot. Called a "snow belt" I think - not quite as complicated as the one in that link. This one seems pretty straightforward, somewhat like heated flashing. I was worried an ice dam would form above it, but that hasn't been the case despite many opportunities. Not quite sure why, I'm sure the builder explained it to me back when I was uncertain of whether to pay the cost.

If it ever does break, though, that'snot gonna be fun.

[Paul Alciatore]

"...to keep water from backing up behind the ice dam and seeping under the shingles which would ruin the wall."

Don't they use tar paper under the shingles in northern climates? It is the first thing they put down on every roof I have ever done myself or seen done. For flat roofs they "mop" it together with hot pitch so it forms a water tight layer under whatever the upper surface is.

The purpose of these is to keep water from backing up behind the ice dam and seeping under the shingles which would ruin the wall. You don't need to worry about the downspouts, just let the water drip off the gutter if it is frozen. The 60 feet lets most people zigzag the wire along the roof edge. Most people do not have a 60 foot long eave without interruptions.

[nickel-city-fab]

"...to keep water from backing up behind the ice dam and seeping under the shingles which would ruin the wall."

Don't they use tar paper under the shingles in northern climates? It is the first thing they put down on every roof I have ever done myself or seen done. For flat roofs they "mop" it together with hot pitch so it forms a water tight layer under whatever the upper surface is.

Yes, they do use tar paper, but the roof has very little protection on the edge of the sheathing where the gutter goes. The surface of the plywood is no problem, it's the very lowest edges where the roofing ends and the gutter begins.
BTW: I live in a trailer north of Buffalo, and the single most important thing is the heat cable that is wrapped around my water line.
It comes on automatic if the temps drop below freezing. Outside of the pipes are insulated 2x layers with foam and mylar.

[RMinMN]

"...to keep water from backing up behind the ice dam and seeping under the shingles which would ruin the wall."

Don't they use tar paper under the shingles in northern climates? It is the first thing they put down on every roof I have ever done myself or seen done. For flat roofs they "mop" it together with hot pitch so it forms a water tight layer under whatever the upper surface is.

Tar paper is not waterproof. It slows the entry but doesn't stop it. In some cities the use of a rubber membrane (which is much more expensive than tar paper) is required for the first 3 feet from the edge of the roof. Even then, nailing the shingles will poke holes in the membrane.