Solar Glass Snow Avalanches

[BGbreeder]

I'm sure it is no fun walking out the front door trying to dodge an avalanche. At this point it seems like you are going to need plywood sheets to protect your shrubs from the snow loads. Very popular in Cleveland and Buffalo...

At this point, yes, I would worry about ice dams and whether if they form whether they would take tiles off.

Post facto: could you have installed heating tape under the tiles?

While I agree that there are issues with heating tape in gutters, and it is definitely better to cure the cause of ice dams rather than making them go away, but sometimes the "cure" is a whole new roof framing ($$$), and heat tape can be a cost effective alternative. I have lived in a home with tape on the roof with no issues and they lasted 15+ years for us. And yes, it was one of those where the "right answer" was an entirely new roof with a different slope. Then again, no rats, no squirrels on the roof, and no mice or woodpeckers attacking the wiring.

I find it hard to believe that the issue of snow/ice avalanches hasn't come up before for Tesla.

All the best,

BG

 

[trautmane2]

he wondered if Tesla had snow guards for the edge of the roof like you would for a slate roof

I'm liking the snow guard idea:
Snow Guards for Metal Roofing

I'm not sure my wife would go for a Tesla branded one though

 

[dhquigley]

I'm liking the snow guard idea:
Snow Guards for Metal Roofing

I'm not sure my wife would go for a Tesla branded one though

I like the idea of black plastic stuck-on guards. Could put them on that bottom row, which I believe is just glass anyway. Hopefully, this is where Tesla ends up. I will say that the gutter guards did appear to help with the damming problem. Also, my neighbor across the street has Tesla panels, not roof, and had same issue. Easier to fix there, as he can put guards on the roof below the panels. I am curious to see if we have the same level of problem with a more "normal" snow. This snow was the worst possible scenario, I think. My next door neighbor thought it was thundering. Nope, just my roof clearing.

 

[jboy210]

This definitely sounds like one of those instances of "Tesla is a California company". Meaning, I wonder how much thought was given to the speed with which snow flows off a solar roof. As said earlier in this thread, for most Californians, Snow is "That stuff we drive to go play in, that stays over there where we vacation".

Not too sure about that. The Solar Roof is made in the Buffalo, NY Gigafactory. They know about snow in Buffalo.

 

[wjgjr]

I like the idea of black plastic stuck-on guards. Could put them on that bottom row, which I believe is just glass anyway. Hopefully, this is where Tesla ends up. I will say that the gutter guards did appear to help with the damming problem. Also, my neighbor across the street has Tesla panels, not roof, and had same issue. Easier to fix there, as he can put guards on the roof below the panels. I am curious to see if we have the same level of problem with a more "normal" snow. This snow was the worst possible scenario, I think. My next door neighbor thought it was thundering. Nope, just my roof clearing.

This was definitely a nasty storm in terms of the mix - just got in from cleaning my car (no garage) and trying to clear my walks, and it is an impressive layer of ice on the pavement. And in some ways I wonder if the one good news about the roof avalanches is they seemed to occur with only a few inches of snow, so hopefully it won't tend to build up feet before the avalanche. The only time I had any issue with my old slate roof was back in 2010 when we had those two huge storms in a row, and when the snow/ice slid off, it completely tore off our rear gutter (and put a nice dent in our A/C unit.)

As far as the roof, it is mostly clear (and I am generating seemingly-normal amounts of power so far with a clear day.) But there is still some snow/ice stacked on the gutters (on top of the guards.) Not a ton, but more than I would like to see. I will certainly be interested to see if anybody installs snow guards.

 

[trautmane2]

heard from the Tesla installers. "Last time [he] checked, Tesla was still developing snow guards for version 3

My install advisor just gave me this same response: "our SolarRoof snow guard is still in design phase".

 

[dhquigley]

Ok. Update number 3. I heard from my tesla advisor. While Tesla does not make a product, people who live in climates like us have success with the following. He said it just adheres. Put it on the bottom on your inactive cells. I have called the roofing company to see if they would do this and at what cost. Let me know if any dmv people want in.

 

[dhquigley]

One more update for you. I spoke with the owner of the company that makes the guards. His website offers a service that maps out where to put the guards based on available area, etc. I will send him some photos and have explained the active/inactive issue. Will try to put him in touch with the roofer we all worked with and see if we cannot put something together. Has to wait until Spring incidentally, given the need for the material to bond in warmer temperatures. Will keep you all posted.

 

[wjgjr]

One more update for you. I spoke with the owner of the company that makes the guards. His website offers a service that maps out where to put the guards based on available area, etc. I will send him some photos and have explained the active/inactive issue. Will try to put him in touch with the roofer we all worked with and see if we cannot put something together. Has to wait until Spring incidentally, given the need for the material to bond in warmer temperatures. Will keep you all posted.

Thanks for doing all the work - will be interested to hear what the recommendations and costs are. And, depending on how much of an issue this proves to be, there will be a question both of whether Tesla will have a solution by then and whether Tesla should be responsible for a fix.

 

[dhquigley]

Thanks for doing all the work - will be interested to hear what the recommendations and costs are. And, depending on how much of an issue this proves to be, there will be a question both of whether Tesla will have a solution by then and whether Tesla should be responsible for a fix.

The guards cost $1.39 each! And you can install them yourself (I cannot, but maybe you can) since the manufacturer will map out where to put them for you. I am trying to get CompleteExteriors, the roofing company who did the tear down, in touch with him so they can work out where to put these. I did not get the sense from Tesla that they were putting forward their fix anytime soon, but since this has to wait until spring for the adhesive to bond anyway, we'll see. Gives them until summer to figure it out.

 

[wjgjr]

The guards cost $1.39 each! And you can install them yourself (I cannot, but maybe you can) since the manufacturer will map out where to put them for you. I am trying to get CompleteExteriors, the roofing company who did the tear down, in touch with him so they can work out where to put these. I did not get the sense from Tesla that they were putting forward their fix anytime soon, but since this has to wait until spring for the adhesive to bond anyway, we'll see. Gives them until summer to figure it out.

I would definitely need somebody to install, so that would probably be the bigger cost than the guards. I also would ideally prefer a Tesla solution to avoid any questions down the road about warranty work.

 

[trautmane2]

Let me know if any dmv people want in

Thanks for working on this! I'm certainly interested in what you learn. My initial reaction to adhesive guards was suspicion about whether they would be strong enough (and for how long).

the manufacturer will map out where to put them for you

I'd love to see that map. This page Snow Guard Spacing and Layout Tool discusses guard spacing for traditional metal roofs with ridges and references this mapping tool: SpacingTool.com Free Instant Snow Guard Spacing Layouts for Snow Guards on Metal Roofs

The snow seemed to shed off of my roof in tile-width sections (maybe triggered by snow/rain sliding between the tile seams and then under them?). Because of this, I'd guess that we could use tile width as our metal roof "panel width" for the mapping. It is interesting that the spacing page recommends a wider distribution of guards - not just one row of them.

If it is necessary to have more than a single row and therefore go into PV tile areas, these shingle snow guards might work if they were nailed underneath our tiles:
Snow Guards For Shingle Roofs

and ... just to keep it entertaining, here's a picture of the avalanche that crashed down while I was writing this post:

 

[wjgjr]

Thanks for working on this! I'm certainly interested in what you learn. My initial reaction to adhesive guards was suspicion about whether they would be strong enough (and for how long).



I'd love to see that map. This page Snow Guard Spacing and Layout Tool discusses guard spacing for traditional metal roofs with ridges and references this mapping tool: SpacingTool.com Free Instant Snow Guard Spacing Layouts for Snow Guards on Metal Roofs

The snow seemed to shed off of my roof in tile-width sections (maybe triggered by snow/rain sliding between the tile seams and then under them?). Because of this, I'd guess that we could use tile width as our metal roof "panel width" for the mapping. It is interesting that the spacing page recommends a wider distribution of guards - not just one row of them.

If it is necessary to have more than a single row and therefore go into PV tile areas, these shingle snow guards might work if they were nailed underneath our tiles:
Snow Guards For Shingle Roofs

and ... just to keep it entertaining, here's a picture of the avalanche that crashed down while I was writing this post:

View attachment 618922

What is interesting is that I experienced a very different behavior - both sides of my main roof (simple, gable roof, with nothing other than a couple pipes/vents to block any slides) when they went, the entire side went - as in the roof went from uniformly covered to over 90% clear, with only a few bits of snow right on the edges that did not come off (and a bit behind the pipes.) The smaller gable roof on one side had the same behavior. After that, we had a couple slides where the rest of the snow came off, but each roof face sent almost everything off in the first shot.

I don't know if that is because of slope, roof shape, or the type of precipitation. I'm thinking it is at least partly that you probably got more (all?) snow, while I got like 1.5" of snow before it turned to rain, creating more of a heavy, slushy mass. Will certainly have to see how it behaves with different storms, assuming we actually get a more normal winter this year (after virtually nothing last year.)

 

[tpoltron]

We have a cabin near Tahoe and many roofs there are steep and slippery by design to shed snow. I need to replace the metal roof on the cabin in a few years and was hoping Solar Glass would shed snow as my roof was not designed to take a non shedding load. You can get 5ft of wet heavy snow in one storm there and it has collapsed more than a few roofs.

 

[h2ofun]

We have a cabin near Tahoe and many roofs there are steep and slippery by design to shed snow. I need to replace the metal roof on the cabin in a few years and was hoping Solar Glass would shed snow as my roof was not designed to take a non shedding load. You can get 5ft of wet heavy snow in one storm there and it has collapsed more than a few roofs.

I thought when folks had roofs basically to deal with snow, one does not use gutters?

 

[tpoltron]

I thought when folks had roofs basically to deal with snow, one does not use gutters?

Correct but I expect the OP is in a place with more rain that snow and his roof originally had composite shingles that snow stuck to so he didn’t worry about his gutters.

 

[h2ofun]

Correct but I expect the OP is in a place with more rain that snow and his roof originally had composite shingles that snow stuck to so he didn’t worry about his gutters.

I know when I was looking at my options for a new roof before I installed my solar, these tiles were an option. But even though my roof is not that steep, and I do not get snow very often, I do walk on my roof enough for various reasons I decided it was safer to just stay with normal composite tiles, and put on normal solar.

 

[trautmane2]

I expect the OP is in a place with more rain that snow and his roof originally had composite shingles

You are correct. Prior to my install, I was focused on the solar and aesthetic aspects of the roof and naively neglected to consider how the glass would have some similar properties to a metal roof (which I've seen but never had). In the mid-atlantic region where we live, we get a lot more rain than snow. I had thought about snow as a solar blocker, but failed to anticipate how the snow might shed off the roof. As @wjgjr mentioned, it is not clear whether the shedding during this recent storm (my first with the solar roof) was typical or anomalous.

I do walk on my roof enough for various reasons I decided it was safer to just stay with normal composite tiles

I would definitely agree that if you need to walk on your roof alot and your roof is relatively steep, solar glass is probably a poor choice.

 

[h2ofun]

You are correct. Prior to my install, I was focused on the solar and aesthetic aspects of the roof and naively neglected to consider how the glass would have some similar properties to a metal roof (which I've seen but never had). In the mid-atlantic region where we live, we get a lot more rain than snow. I had thought about snow as a solar blocker, but failed to anticipate how the snow might shed off the roof. As @wjgjr mentioned, it is not clear whether the shedding during this recent storm (my first with the solar roof) was typical or anomalous.



I would definitely agree that if you need to walk on your roof alot and your roof is relatively steep, solar glass is probably a poor choice.

Same reason I looked at metal and said no thanks

 

[SMAlset]

Too bad you can’t use an air horn to send the roof avalanche down when needed! Wouldn’t make you loved by your neighbors however .

In mild area of California now but having lived back East and the mid-West I know this can be a dangerous situation. A few years back a neighbor of my mom’s back east died trying to clean the heavy snowfall they had received. Feet of snow and ice came down on him, actually knocking him to the ground and burying him. He lived alone and no one knew he was out there. Not sure if he was knocked unconscious or what but he ultimately froze to death. Very sad really to lose your life over removing snow from your roof.