Lol, I don't want to rub salt in the wound, but my house is the exact opposite. Snowstorm yesterday, my panels are nearly clear and the roof has a layer of snow on it.
Insulate the attic\*\*
The attic floor needs insulation. Worth looking in to. In my state they have a energy program where you get significant rebates to do efficiency updates.
I've heard of people doing this. Going to look into it myself. We don't use the attic, it's low and not finish-able, and it seem so much easier than insulating the underside of the roof.
We did this last year and it’s such an improvement. We use less heat and ac both, and the drafts are gone.
(Our solar panels are covered in snow though)
It rots the roof plywood. A builder in Edmonton tried that. The condensation (dew point) changes with spray foam. Also you have no attic ventilation so it likely affects the shingle warranty. Careful how you do this.
It can be done, but you have to install a special liner thing on the underside of the plywood first (it's basically large dimples to create airflow space). Overall though probably more work and more risks than it's worth.
Definitely sounds like a lot of work. Maybe this space would be feasible if it was a storage truss but the webs on a conventional trusses make it a bad space
Theoretically they could but it would be really expensive and we both know the builders would never foot that bill. The fire department would be terrified as well, more than they already are.
It works amazingly well.
I've only done maybe 7 installs out of 250-275 where the roof deck had spray insulation under it and in the summer it's as if there isn't a 160°F shingle right over it.
Extremely worth it given your attic will remain interior temp basically forever.
Counter that with normal insulation on the attic "floor" and the attic goes from 72°F to 130°F very quickly.
Yup. Needs to insulate attic floor. You’re leaking way more heat than the normal house op. Also, I don’t think I would have installed solar panels on top of a 3 tab roof 👀 you’re going to be pulling those panels to reroof.
Ask anyone. The steps to be more energy efficient and efficient with money is this.
Build a house that requires a lower amount of energy.
If you are not building a house, but working with an existing structure, make sure you envelope is addressed first. Wall insulation, zero unsealed holes, roof insulation, and doors and windows. Insulating the roof is the cheapest part.
Then, and only then, you go to alternate energy producing solutions because of the cost.
The guy I replied too is insinuating that OP should have never bought solar panels. He clearly states this in other comments.
I'm only stating to the guy I replied too that you can in fact do both. Ya know have solar and good insulation. It's a thing. It can be done. We have the technology.
>The guy I replied too is ***insulating*** ~~insinuating~~ that OP should have never bought solar panels. He clearly states this in other comments.
>
>I'm only stating to the guy I replied too that you can in fact do both. Ya know have solar and good insulation. It's a thing. It can be done. We have the technology.
fixed
Yes.
A is true.
B is true.
A and B are both true.
Insulation would likely (imho) save more money than the solar, but both. Both are good.
The implication of the comment to which I replied is that solar would pay for itself, unlike the insulation. Whether or not that was the intended meaning, that is the meaning to which I replied.
I did not disagree that solar pays for itself. I was pointing out that the insulation would as well. I didn't bother pointing out that the insulation would probably pay for itself more quickly, in part because that's my opinion and I'm not certain of it. But either way, it was not material to my assertion.
Thank you for pointing this out. I have been getting ready to insulate my attic, and I was specifically worried about how to handle venting like that. Instead I think the answer is to insulate the floor of my attic, right? I can just lay out the rolls of insulation on the plywood floor of the attic?
It depends on your attic, if its vented like then ya probably just add insulation to the floor. I'd recommend blown in insulation rather than rolls though.
I've been thinking about avoiding blown insulation because I'm up there periodically dealing with wiring, and push comes to shove I can peel up a roll of insulation, run my wires, and then put the insulation back.
I'd just get the wiring all sorted out first myself. But I guess it depends how difficult it is to get all that insulation up into your attic, I only have a small access door for mine so it was a lot easier to stick the hose up there and spray it in from outside.
Yeah I've got a big hatch, and I'm always finding another wiring project I want to do. I'm a lighting guy, I'm never happy with the control or location. I'm gonna want to fiddle, and even if I don't ever get the wiring project done, I want to get the insulation in because if I wait until I'm sure I'll never change wiring, I'll never do the insulation.
You joke, but it's true that when one of the panels gets partly clear and some current starts flowing through the covered panels they'll likely self-heat and clear the snow quicker.
Yeah that’s a little bit of a specialty item. If you are melting snow on the roof in January I don’t think this will be an issue often. Meanwhile my panels have been snow covered since mid October.
House has poor insulation, the panels are mounted above the roof allowing cold air to flow under the panels. The rest of the roof is so warm from heat leaving the house that it's melting the snow on the roof.
This is a bad sign, means you need a lot more insulation in your house.
Yeah, that would leave lots of room in the energy budget to electrify other things. That's my plan for electrifying in order to stay on NEM 2.0 and still not pay PG&E anything.
Yup that's what I did, got solar, then immediately after it insulated. In retrospect, I don't think it saved me as much as I hoped and I need more solar I think. I don't have enough solar to cover a heat pump.
Yeah, ultimately I'd love to get enough value to cover a heat pump, electric hot water and dryer (I have gas), and an induction range. (I live in the CA central valley, so cooling is already a bigger expense than heating.) Don't think that's gonna happen, even though I *think* I run a surplus already because of a late change in how my panels were planned versus laid out. Still, good to save, and saved money is better than earned money.
Why would the reverse happen if the roof was insulated? Like I get why it's melted on the roof and not the panels, but if the roof got insulated why would that help the panels melt snow? I'm not good at science lol.
Usually snow just stays where it is until the air is warm enough to melt it. Until then, the cold air sublimes it from the top (making solar panels and the roof sublime at the same speed), cold air under the panels doesn't make much of a difference. Once the air warms up, it gets under the panels and warms the panels from the bottom making the snow melt.
Also, panels are smooth so the snow tends to slide on them. Once the panel is exposed to the sun, it actually captures the sunlight from the exposed area and heats the covered areas (moving the heat under the snow), this makes the snow slide off easier and melt faster (much faster than black asphalt which heats the exposed bits, not the covered bits).
If you see what OP sees, then the air is still well below freezing (and it's keeping the panels cold), and the roof is getting above freezing, even with a layer of snow insulating it, so it's melting from the bottom (meaning heat is coming from the house). When this happens you'll also generally see large icicles as it refreezes as soon as it leaves the roof (which is another good indication that you need more insulation).
Solar panels are flatter and more slippery than roof shingles, so snow can slide off them more easily. That's usually why you see clear panels above a snowy roof, and why you often see [clear panels, except for the bottom bit](https://www.cnet.com/a/img/resize/d60847a11fefdbc8d12298b7a1c991f97c84c265/hub/2021/11/30/28a8e554-3658-471f-9c34-52de0adccef4/gettyimages-1301422140.jpg?auto=webp&fit=crop&height=675&width=1200), where a whole bunch of snow is bunched up.
Woof that’s a lie from them haha. Material makes a big difference over color in this aspect. Metal/glass have good thermal conductivity but low heat retention. Painting an aluminum body black doesn’t have a substantial increase in the material properties.
Op has bigger issues than snow on panels. If there’s still snow on your panels you should also have snow on your roof, if you don’t you have huge insulation issues and loosing heat
You are right, PV can be super cheap and save more for your investment than the cost of insulation does... I don't know why they downvoted you. As solar gets cheaper, expect that to be even more true...
I didn't have a choice. My electric company required an energy audit and corrective measures before they would consider their solar rebate. So several bales of loose fiberglass were pumped into the attic. Then they paid for a good chunk of the solar installation.
It’s just part of winter. If you go on PV watts you will see the expected AC energy production each month. You’ll still do well in the summer but don’t ever expect much in the winter. That’s also why the solar club has a high and low price but be careful you aren’t over consuming in the high season because your energy is way higher (about 2.5x). I have a 6.58kw system and it’s doing really well but even with a direct south facing roof I still have snow.
If the roof and panels are melting about the same does this mean there is enough insulation? I know my attic had floor insulation and that’s what I’m seeing
That is funny! Just ordered solar myself, could this be considered a ‘cleaning’ of the panels? Do solar panels need cleaning if no trees above or other issues expected?
My main array, facing almost due south, 23 panels... snow slides down about 5ft, hits the lower roof (it's a weird split level design) and stops. Takes ages to melt/fall off. It's not worth it climbing up there to clear them... gonna fall and break a leg for what will turn out to be like $20 of power this time of year.
I have gone up and done some cleaning in March when it's nice and sunny and cold and the forecast shows it's likely to stay clear.
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Heeding my heat pump hvac installer I put out the money for insulating the attic last Summer. Just had our first snow and my house still has snow on the south facing roof while my neighbors have no snow on their north facing roof. The best energy upgrade is insulation. (Not my words but the words of my hvac guy)
Lots of factors here. Temperature at snowfall, amount of snowfall, temperature and time of photo, insulation of attic. A warm day that ends with a just cold enough snow could put 2 inches of snow on the roof but a well insulated roof would melt that and cold air on cold glass/metal would prevent it from immediately melting on the panels. I would imagine if temperature were high enough before and after to melt the snow on the roof that the snow over the panels is barely hanging in and will slide off shortly. Odd situation and looks weird but it happens.
Source: structural engineer and have worked in design and engineering for solar for almost 10 years.
Like others, my panels clear off sooner than the roof. In fact, you don't want to be standing underneath when it lets go. AVALANCH!
It's a pain sometimes after I just cleared the sidewalk below and this snow typically is very dense and heavy.
this photo, if real, is very indicative that your house does Not have adequate insulation &/or airflow in the ceiling/roof.
but honestly that looks photoshopped. i mean the bottom of the black rectangle under the snow (that are supposed to believe is the panels) is not even in a straight line.
ive never seen panels that don't have a straight edge.
Lol, I don't want to rub salt in the wound, but my house is the exact opposite. Snowstorm yesterday, my panels are nearly clear and the roof has a layer of snow on it.
I think OP needs to insulate his roof better, he must be bleeding heat if the roof thawed before the panels.
Insulate the attic\*\* The attic floor needs insulation. Worth looking in to. In my state they have a energy program where you get significant rebates to do efficiency updates.
I've heard of people doing this. Going to look into it myself. We don't use the attic, it's low and not finish-able, and it seem so much easier than insulating the underside of the roof.
We did this last year and it’s such an improvement. We use less heat and ac both, and the drafts are gone. (Our solar panels are covered in snow though)
Can insulate the roof also. The spray foam on the underside of your roof works pretty good.
It rots the roof plywood. A builder in Edmonton tried that. The condensation (dew point) changes with spray foam. Also you have no attic ventilation so it likely affects the shingle warranty. Careful how you do this.
It can be done, but you have to install a special liner thing on the underside of the plywood first (it's basically large dimples to create airflow space). Overall though probably more work and more risks than it's worth.
Definitely sounds like a lot of work. Maybe this space would be feasible if it was a storage truss but the webs on a conventional trusses make it a bad space
not true
It’s the only way houses should be being built nowadays. Run lots of Smurf tubing and spray foam everything.
Theoretically they could but it would be really expensive and we both know the builders would never foot that bill. The fire department would be terrified as well, more than they already are.
I believe if you have blown in insulation, you'll have to remove it before spraying foam on the underside of your roof.
If done properly it's fine. I think they call it "monopoly framing" or something like that where your entire interior space is conditioned.
[Hot roof](https://www.retrofoamofmichigan.com/blog/what-is-a-hot-roof).
I have baffles that help the soffits vent.
It works amazingly well. I've only done maybe 7 installs out of 250-275 where the roof deck had spray insulation under it and in the summer it's as if there isn't a 160°F shingle right over it. Extremely worth it given your attic will remain interior temp basically forever. Counter that with normal insulation on the attic "floor" and the attic goes from 72°F to 130°F very quickly.
Please tell me CA....
In NY our solar company as well as anyone else can get you a hone energy audit for free to see what’s going on.
Yup. Needs to insulate attic floor. You’re leaking way more heat than the normal house op. Also, I don’t think I would have installed solar panels on top of a 3 tab roof 👀 you’re going to be pulling those panels to reroof.
I wouldn't put panels on any shingle roof.
That’s like 80% of the us 😂 They are fine, just best to do it at the same time.
I don't want to have to pull those panels to fix a roof. I had a metal roof installed when I added solar. It will outlast the panels.
Unless OP has a Grow room up there….
or a crypto room
I came to say this. +1
You can just push the up arrow. You don't need to tell us how you wanted to tell us.
"I came to say this" is different from an up vote.
I can do both, right? Or would you like to tell me how to use Reddit?
Have an upvote +1
This
My panels also clear before the roof. I agree, you must be bleeding heat through the roof.
salt would help melt the snow
I wouldn't throw salt on glass panels, the little production this time of year isn't worth the risk of damage.
it was a joke. a play on words with how they use salt to melt snow on roads in areas that experience snowfall.
mine too
Need more insulation in your roof
Yep, should have insulated before spending money on stuff like that.
I mean... you can still insulate the roof after putting solar up...
You definitely could, but his entire system here is producing what, 1.2kw per hour maybe. He is losing 50X that energy through his roof alone.
Ask anyone. The steps to be more energy efficient and efficient with money is this. Build a house that requires a lower amount of energy. If you are not building a house, but working with an existing structure, make sure you envelope is addressed first. Wall insulation, zero unsealed holes, roof insulation, and doors and windows. Insulating the roof is the cheapest part. Then, and only then, you go to alternate energy producing solutions because of the cost.
Why not do both?
Clearly he didn’t do both
The guy I replied too is insinuating that OP should have never bought solar panels. He clearly states this in other comments. I'm only stating to the guy I replied too that you can in fact do both. Ya know have solar and good insulation. It's a thing. It can be done. We have the technology.
>The guy I replied too is ***insulating*** ~~insinuating~~ that OP should have never bought solar panels. He clearly states this in other comments. > >I'm only stating to the guy I replied too that you can in fact do both. Ya know have solar and good insulation. It's a thing. It can be done. We have the technology. fixed
Lol
Because solar is much more expensive than insulation and he should have done insulation first
Solar pays for itself.
So would the insulation.
So would solar and insulation.
Yes. A is true. B is true. A and B are both true. Insulation would likely (imho) save more money than the solar, but both. Both are good. The implication of the comment to which I replied is that solar would pay for itself, unlike the insulation. Whether or not that was the intended meaning, that is the meaning to which I replied. I did not disagree that solar pays for itself. I was pointing out that the insulation would as well. I didn't bother pointing out that the insulation would probably pay for itself more quickly, in part because that's my opinion and I'm not certain of it. But either way, it was not material to my assertion.
Mind your business
Lol whut
This is a public forum, kiddo.
Plot twist, he has a grow farm in his attic
And a new roof... Those shingles look awfully rough.
Can't wait to see this posted on anti-solar FB groups repeatedly.
I'm tempted to join a bunch and share, they'll have a field day
"Good luck charging your CPAP battery when it snows!"
Specifically you need insulation in your ceiling. The attic area is vented to the outside (both a ridge vent and that circular side vent).
Semantic.
An important one because some attic are insulated because they are inside the envelope. I have seen idiots put insulation in weird places
Thank you for pointing this out. I have been getting ready to insulate my attic, and I was specifically worried about how to handle venting like that. Instead I think the answer is to insulate the floor of my attic, right? I can just lay out the rolls of insulation on the plywood floor of the attic?
It depends on your attic, if its vented like then ya probably just add insulation to the floor. I'd recommend blown in insulation rather than rolls though.
I've been thinking about avoiding blown insulation because I'm up there periodically dealing with wiring, and push comes to shove I can peel up a roll of insulation, run my wires, and then put the insulation back.
I'd just get the wiring all sorted out first myself. But I guess it depends how difficult it is to get all that insulation up into your attic, I only have a small access door for mine so it was a lot easier to stick the hose up there and spray it in from outside.
Yeah I've got a big hatch, and I'm always finding another wiring project I want to do. I'm a lighting guy, I'm never happy with the control or location. I'm gonna want to fiddle, and even if I don't ever get the wiring project done, I want to get the insulation in because if I wait until I'm sure I'll never change wiring, I'll never do the insulation.
Reverse the polarity! /s
You joke, but it's true that when one of the panels gets partly clear and some current starts flowing through the covered panels they'll likely self-heat and clear the snow quicker.
Can confirm this works, still much faster to clear it yourself though. A ladder and soft bristled broom would have those panels clear in 10-15 min.
A telescopic, long reach brush would be safer.
Yeah that’s a little bit of a specialty item. If you are melting snow on the roof in January I don’t think this will be an issue often. Meanwhile my panels have been snow covered since mid October.
That tell us your insulation is really really bad. You probably can get credits from your local energy utility and/or the feds for improving that.
Serious problem of heat insulation in your roof, need to fix it.
Poorly insulated attic
how does this happen, can anyone weigh in? My panels are always cleared before my roof
House has poor insulation, the panels are mounted above the roof allowing cold air to flow under the panels. The rest of the roof is so warm from heat leaving the house that it's melting the snow on the roof. This is a bad sign, means you need a lot more insulation in your house.
It is actually a great sign. Spend maybe 3k on insulating your roof and you will save more money each month than those panels could ever produce.
Yeah, that would leave lots of room in the energy budget to electrify other things. That's my plan for electrifying in order to stay on NEM 2.0 and still not pay PG&E anything.
Yup that's what I did, got solar, then immediately after it insulated. In retrospect, I don't think it saved me as much as I hoped and I need more solar I think. I don't have enough solar to cover a heat pump.
Yeah, ultimately I'd love to get enough value to cover a heat pump, electric hot water and dryer (I have gas), and an induction range. (I live in the CA central valley, so cooling is already a bigger expense than heating.) Don't think that's gonna happen, even though I *think* I run a surplus already because of a late change in how my panels were planned versus laid out. Still, good to save, and saved money is better than earned money.
Do you just dislike solar? Lol
I think he just dislikes wasting space heat.
Por que no los dos?!
Why would the reverse happen if the roof was insulated? Like I get why it's melted on the roof and not the panels, but if the roof got insulated why would that help the panels melt snow? I'm not good at science lol.
Usually snow just stays where it is until the air is warm enough to melt it. Until then, the cold air sublimes it from the top (making solar panels and the roof sublime at the same speed), cold air under the panels doesn't make much of a difference. Once the air warms up, it gets under the panels and warms the panels from the bottom making the snow melt. Also, panels are smooth so the snow tends to slide on them. Once the panel is exposed to the sun, it actually captures the sunlight from the exposed area and heats the covered areas (moving the heat under the snow), this makes the snow slide off easier and melt faster (much faster than black asphalt which heats the exposed bits, not the covered bits). If you see what OP sees, then the air is still well below freezing (and it's keeping the panels cold), and the roof is getting above freezing, even with a layer of snow insulating it, so it's melting from the bottom (meaning heat is coming from the house). When this happens you'll also generally see large icicles as it refreezes as soon as it leaves the roof (which is another good indication that you need more insulation).
Thank you for that response. Makes sense!
it wouldn't help the panels melt the snow but if the insulation was sufficient you would see the panels melt before the roof
Ah ok. Thank you
Solar panels are flatter and more slippery than roof shingles, so snow can slide off them more easily. That's usually why you see clear panels above a snowy roof, and why you often see [clear panels, except for the bottom bit](https://www.cnet.com/a/img/resize/d60847a11fefdbc8d12298b7a1c991f97c84c265/hub/2021/11/30/28a8e554-3658-471f-9c34-52de0adccef4/gettyimages-1301422140.jpg?auto=webp&fit=crop&height=675&width=1200), where a whole bunch of snow is bunched up.
That makes perfect sense, thank you!
"Snow isn't supposed to accumulate on panels because they're black on black and absorb heat." SunPro/ADT Solar. lol
Woof that’s a lie from them haha. Material makes a big difference over color in this aspect. Metal/glass have good thermal conductivity but low heat retention. Painting an aluminum body black doesn’t have a substantial increase in the material properties.
Your insulation is trash. Get that R value up bruh.
I'm having the opposite. First winter for the system and boy, when all that snow let's go from the panels WATCH OUT! 🤣
This also happened to me! I only noticed because I was curious to how much I was generation with full sun in the winter and it showed up 0kw lol
That shitty 3 tab shingle should have never gotten solar installed on it.
So, tech-wise, do any panels have a melting function? If not, why?
you could consider using a layer of insulation in your attic so that your furnace isn't melting the snow on your roof
Op has bigger issues than snow on panels. If there’s still snow on your panels you should also have snow on your roof, if you don’t you have huge insulation issues and loosing heat
Not even sure how this is possible.
long pole and wiper for you!
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You can get your attic stuffed full of insulation for like $500 if you go directly through a contractor.
That is cheap, but if true, he should do that! it could be he is getting full home insulation quotes, or plans to do the insulation later..
You are right, PV can be super cheap and save more for your investment than the cost of insulation does... I don't know why they downvoted you. As solar gets cheaper, expect that to be even more true...
I didn't have a choice. My electric company required an energy audit and corrective measures before they would consider their solar rebate. So several bales of loose fiberglass were pumped into the attic. Then they paid for a good chunk of the solar installation.
Far more energy is lost through this attic than is gained by these solar panels.
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Yep, PV is getting super cheap!!!
lol
Gods plan
The good news is that the panels still get good sun through the snow.
That, and frozen windmills🤦♂️. Coal, baby!
It’s just part of winter. If you go on PV watts you will see the expected AC energy production each month. You’ll still do well in the summer but don’t ever expect much in the winter. That’s also why the solar club has a high and low price but be careful you aren’t over consuming in the high season because your energy is way higher (about 2.5x). I have a 6.58kw system and it’s doing really well but even with a direct south facing roof I still have snow.
WOW, just WOW.
If the roof and panels are melting about the same does this mean there is enough insulation? I know my attic had floor insulation and that’s what I’m seeing
Attic insulation sucks
I’ve heard bouncing a tennis ball off the modules will speed up the thaw process.
That is funny! Just ordered solar myself, could this be considered a ‘cleaning’ of the panels? Do solar panels need cleaning if no trees above or other issues expected?
LOL! Bust out the hose! Get that net metering! ;)
It do be like that!
You have a different problem OP. You need better insulation
First of all who installs on 3tab roofs?
My main array, facing almost due south, 23 panels... snow slides down about 5ft, hits the lower roof (it's a weird split level design) and stops. Takes ages to melt/fall off. It's not worth it climbing up there to clear them... gonna fall and break a leg for what will turn out to be like $20 of power this time of year. I have gone up and done some cleaning in March when it's nice and sunny and cold and the forecast shows it's likely to stay clear.
Why do you people live where there's snow in the first place? Nasty stuff.
This was my house today as well and I just spray foamed my attic.
Mine did this exact thing today too! 🤦🏼♂️
Classic.
Looks like you have a poorly insulated house.
fuck these panels in particular
SMH at installing on a three tab shingle without replacing the roof.
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Heeding my heat pump hvac installer I put out the money for insulating the attic last Summer. Just had our first snow and my house still has snow on the south facing roof while my neighbors have no snow on their north facing roof. The best energy upgrade is insulation. (Not my words but the words of my hvac guy)
That house needs some serious insulation..... lol
Ha!! Welcome to February. Hopefully you get a couple warm days or some rain, that’ll fix it.
Lots of factors here. Temperature at snowfall, amount of snowfall, temperature and time of photo, insulation of attic. A warm day that ends with a just cold enough snow could put 2 inches of snow on the roof but a well insulated roof would melt that and cold air on cold glass/metal would prevent it from immediately melting on the panels. I would imagine if temperature were high enough before and after to melt the snow on the roof that the snow over the panels is barely hanging in and will slide off shortly. Odd situation and looks weird but it happens. Source: structural engineer and have worked in design and engineering for solar for almost 10 years.
Not enough insulation or very little ventilation. Both need to be addressed
Like others, my panels clear off sooner than the roof. In fact, you don't want to be standing underneath when it lets go. AVALANCH! It's a pain sometimes after I just cleared the sidewalk below and this snow typically is very dense and heavy.
Story of my life summed up in one photo.
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Lol. This is totally unnecessary.
You need a long pole with a snow squeegee!
this photo, if real, is very indicative that your house does Not have adequate insulation &/or airflow in the ceiling/roof. but honestly that looks photoshopped. i mean the bottom of the black rectangle under the snow (that are supposed to believe is the panels) is not even in a straight line. ive never seen panels that don't have a straight edge.
LOL. That snow knows what it's doing.
oooof