Pole Barn

[woodman]

I am near the point of putting in a pole barn. The business can no longer operate out of the old hay barn any longer. There are some critical issues I need to address though and I thought you folks could provide some wisdom, so here goes. I wanted to orient the gable ends to the east and west so that I could put in solar panels in the future but it just won't work that way. Because of the layout of my driveway and other factors such as a metal roof and snow coming off it, I will need to have the gable ends north and south. Is this a beg deal in anyone's opinion? How significant is the amount of power generated from roof panels? I don't believe panels would work well if put on an east or west side. I've never had a pole building before so anyone who is familiar with owning one, chime in. I have been considering attic trusses for office space above. I am thinking of putting in plenty of windows even though it adds to the cost. Appreciate any input.

[palani]

Seems a lot of people around here are putting up hoop buildings with fabric roofs. They seem to survive the windstorms too.

[hoarder]

Would you have room to have a lean-to on the South gable?

[woodman]

Would you have room to have a lean-to on the South gable?

Yes, but that is the only approach and would be where the garage door would go. The snow in the winter would slide right down into the drive.

[woodman]

Seems a lot of people around here are putting up hoop buildings with fabric roofs. They seem to survive the windstorms too.

That is probably a decent answer for agricultural purposes. Cheap too.

[hoarder]

Yes, but that is the only approach and would be where the garage door would go. The snow in the winter would slide right down into the drive.Not having seen the site, known the roof pitch or how many square feet of panels the project entails, I can only make some guesses.
Even if snow removal wasn't an issue, roof pitch on a gable end would mean the garage door would have to be low because the eaves of the lean to would be low.
If steep terrain is an issue, big yellow machines can reconfigure sites in a short time at a reasonable cost....sometimes.
East and West facing panels will not cut it, they have to be within 14 degrees of true south.
You could build a large panel rack somewhere on the site at the optimum angle. That would be more feasable than angled mounts on the roof.

[Cebu_4_2]

I had a 30 x 60 pole barn. Metal sides and roof, the roof pitch was towards the entrance and driveway (fall on your head style). This was in MI so I understand your concerns but it really was a non issue. The ceiling was 1" reinforced reflective foam with 2 foot insulation pumped above. The attic never got warm enough to melt snow or ice. The only time snow/ice would be an issue was a couple times when it got warmer in spring but when it started dripping common sense came into play.

They say double glass from shower doors don't loose too much energy and with sunshine it would gain heat but I never tried that. My idea would have been to have a hinged panel of reflective foam to close it at night when there was no light.

No clue about solar panels. MI don't have the greatest sun angle.

[hoarder]

Other factors to consider on pole barns is frost upheaval can push the poles up if not done right, especially if you have clay soils with poor drainage. Also, roof overhang on the eaves helps keep underground portion of poles dry.

[midnight rambler]

Seems a lot of people around here are putting up hoop buildings with fabric roofs. They seem to survive the windstorms too.

What fabric are they using and where are they getting it?

[midnight rambler]

That is probably a decent answer for agricultural purposes. Cheap too.

Doesn't have to be strictly for ag purposes.

[hoarder]

Doesn't have to be strictly for ag purposes.I wouldn't store valuables in a structure with a fabric roof.

[palani]

What fabric are they using and where are they getting it?

http://www.span-techbuildings.com/documents/filelibrary/documents/canvas_specifications/canvas_specifications_8A1DCB4A94FF6.PDF

12 oz - 22 oz poly coated canvas

http://www.iowafabricbuildings.com/

[midnight rambler]

I wouldn't store valuables in a structure with a fabric roof.

Why? A properly built hoop structure will withstand winds at least as well as stick built with a comp roof. A comp roof gets blown off and it rains = damaged valuables.

[hoarder]

Why? A properly built hoop structure will withstand winds at least as well as stick built with a comp roof. A comp roof gets blown off and it rains = damaged valuables.I was thinking in terms of youfs with pocket knives.

[vacuum]

What's your lattitude, are the skies normally clear or cloudy, and what range of roof pitches are possible on the building?

With those pieces of information I could look into researching what impacts they would have on available solar power.

[Libertytree]

What's your lattitude, are the skies normally clear or cloudy, and what range of roof pitches are possible on the building?

With those pieces of information I could look into researching what impacts they would have on available solar power.

Great Q's vacuum. Also, a needed piece of info is the degree of sight line to the southern tree line.

[woodman]

What's your lattitude, are the skies normally clear or cloudy, and what range of roof pitches are possible on the building?

With those pieces of information I could look into researching what impacts they would have on available solar power.

I intend the roof to be a 12/12 in order to accommodate attic trusses. I want a workshop/office above. The skies in MI are 50\50 but getting worse with the contrail-chemtrails. I will not discount the solar panel issue though. It seems they are getting better all the time and I don't want to make a decision that I will regret in the future. I just wish the layout here was different. There seems to be no reasonable way to change the fact of having the gable ends on a north-south axis. I greatly appreciate all the input. You folks are an invaluable resource. I figured to get a lot of replies from those who have had pole barns. I used to build a few of them but have never owned one myself and owning one is the best way to know what is good and what is not.

[hoarder]

I intend the roof to be a 12/12 in order to accommodate attic trusses. If the ridge was East-West, that 12 in 12 pitch would give you perfect winter sun.
There seems to be no reasonable way to change the fact of having the gable ends on a north-south axis.Then find an unreasonable way.

[woodman]

If the ridge was East-West, that 12 in 12 pitch would give you perfect winter sun.Then find an unreasonable way.

It sounds like the power generated by the panels is a significant thing. This is precisely why I wanted to discuss this. Just how much power can I get from a 30 by 40 pole barn roof? Is it going to provide appreciable output in the winter?

[hoarder]

It sounds like the power generated by the panels is a significant thing. This is precisely why I wanted to discuss this. Just how much power can I get from a 30 by 40 pole barn roof? Is it going to provide appreciable output in the winter?Maybe up to 17000 watts on a sunny day. Nothing when covered by snow. Somewhere in between (towards the low side) on overcast days. My home is powered by 750 watts, just to give you an idea.

[vacuum]

I intend the roof to be a 12/12 in order to accommodate attic trusses. I want a workshop/office above. The skies in MI are 50\50 but getting worse with the contrail-chemtrails. I will not discount the solar panel issue though. It seems they are getting better all the time and I don't want to make a decision that I will regret in the future. I just wish the layout here was different. There seems to be no reasonable way to change the fact of having the gable ends on a north-south axis. I greatly appreciate all the input. You folks are an invaluable resource. I figured to get a lot of replies from those who have had pole barns. I used to build a few of them but have never owned one myself and owning one is the best way to know what is good and what is not.

Cloudy days cause the sunlight to be diffuse, which means that it comes from the sky equally in all directions. Therefore, under cloudy conditions, having the solar panel laying horizontally and pointing strait up is actually the best orientation. So optimally, if you can't have them pointing south, it would be best if they could be pointing upwards as much as possible. (source (http://www.ftexploring.com/solar-energy/direct-and-diffuse-radiation.htm))

Solar panels made out of organic materials are especially good at taking in power from wide angles, whereas traditional solar panels are more optimized for direct sunlight. So organic-based solar panels would possibly be the best choice for collecting indirect or reflected light. (source (http://www.motherjones.com/environment/2014/04/you-can-make-solar-panels-work-cloudy-cities))

For your location, assuming you were at the optimum tilt, if you were 90 degrees rotated from south, you'd only get 77% of the power compared to if you were directly facing south. If the building was 45 degrees rotated from south, you'd get about 93% of the power. (source (http://www.ftexploring.com/solar-energy/tilt-angle3.htm)) But since there are cloudy conditions, it might make it slightly less impactful.

The optimim tilt for your location, while facing south, is about 35 degrees, and a 12/12 roof is steeper at 45 degrees.

So overall, I'd estimate you would take lets say a 33% reduction in power due to the way they're oriented, assuming there aren't any obstructions causing shadows.

A 100 watt panel is about 8 square feet, or in other words 12.5 watts per square foot.

If you did a 20' x 30' portion of the roof covered in panels, that's 600 square feet. That gives about 7500 watts worth of solar panels. Because of the way they're mounted, reduce the available power by 33% and it comes out to about 5000 watts of peak solar power during the day.

Under bad conditions during winter, it may reduce to only 30% of that. So the 5000 watts goes down to 1500 watts. Snow however reflects 80 - 90% of light, and since you're at a steep pitch, the panels might actually get a lot of power from light reflected off of snow.

The full 30 x 40 area is 1200 sq ft, so just double all these numbers.

[reststop]

Maybe up to 17000 watts on a sunny day. Nothing when covered by snow. Somewhere in between (towards the low side) on overcast days. My home is powered by 750 watts, just to give you an idea.

Seems like a read somewhere that a snow cover of up to 6 inches has little effect solar panel output. Would have to do research to confirm.


rest

[hoarder]

Seems like a read somewhere that a snow cover of up to 6 inches has little effect solar panel output. Would have to do research to confirm.


restEven a half inch of snow and output goes to zero.