Snow Load

[Navigator]

Sitting here in a nice warm comfortable house, I see the snow piling up on my coach outside. Am starting to get worried.
Has anyone done any calculations on how much snow a dual axle 31 ft. A/S can take, or more precisely weight of powdery snow per inch of snow. Man I dont want to go out on a ladder in that stuff.
Dick

[CanoeStream]

This isn't exact but is from Ask Jeeves: Heavy snow occurring in 25-35 degree weather can contain 3" or a bit more water per foot. Colder, fluffy snow can be 2" and up per foot. The overall weight on top of a trailer shouldn't be excessive. You aren't bouncing your trailer down the road and a lot of the snow will slide off the rounded sides of the roof.

I would worry more in constant cold conditions where snow can slump and turn icy, then collect more snow on top of the first. You shouldn't have to worry about multiple freeze/thaw cycles.

Good question -- other North-Central members please pipe in:

[wahoonc]

Turn the furnace on about 60 and the snow will melt right off I found out just how thermally efficient Airstreams ain't I have left the heat running on mine because I am working in it over the winter. We picked up 3" of snow a couple of weeks ago, by late after noon you could see where the ribs were. Yesterday we picked up 1" snow with 1/4" of ice with more on the way, but it just kind of melts and runs down. BTW the power was out for a couple of hours around lunch time, just went to the AS and fired up the stove and cooked a big pot of stew and grilled cheese for lunch for everybody...who says an AS doesn't come in handy

Aaron

[CanoeStream]

Good observation Aaron -- but what hitch height do you use to keep your tanks from hitting bumps in the road...?

Are your tanks well secured at the top to keep them from tipping over? This is always the first lesson in dealing with SCUBA and tanks for medical gasses -- and they aren't even flammable.

[wahoonc]

Originally posted by Canoe stream
Good observation Aaron -- but what hitch height do you use to keep your tanks from hitting bumps in the road...?

Are your tanks well secured at the top to keep them from tipping over? This is always the first lesson in dealing with SCUBA and tanks for medical gasses -- and they aren't even flammable.

Canoe stream,

You mean the hoses won't keep the tanks from turning over There is a piece of aircraft cable running thru the collars and fastened to the LP rack on the AS. The hitch height still remains to be seen. Actually just got my 30# worthington's back. But given the cold weather and the amount of LP I have been going thru I might just stick with the 100#'ers for a little longer.

Aaron

[Navigator]

Canoe,
Thanks for the input. I used your #'s and made the following assumptions:
8ft. wide trailer has 7ft. width of snow (6" ea. side flows off)
1 foot of snow has 2" of water
1 cubic foot of water weighs 62.32 lbs.


......than 1" of snow weighs approx. 6#/linear foot of trailer

if you use 3#/ft. than its 9#/linear foot of trailer, or

in my case with 4" of snow and an effective length of 29 feet of trailer, the snow load is 1054#.

I'm going out with the broom.

Dick

[CanoeStream]

I had trouble when I divided acre-feet by furlongs-per-fortnight. Still I came up with a top end of 1000# total load. I don't think that's a big problem and it won't be up there long for you in Delaware -- even with the colder temp high pressure (blue sky) following a snowstorm. If 100 of us get up on ladders somebody is going to get hurt. I suspect we'll get more northerners providing their feedback this evening...

[hohne]

...You might be able to blow it off with your 200 MPH leaf blower...

[Silvertwinkie]

You know, I had my furnace on upwards of 72 degrees and the I found that on the Safari, it barely melted anything on the roof.....seriously!

[wahoonc]

Eric,
That is because you have one of the fancy new thermally efficient Airstreams Besides I can buy a lot of LP for the price diffence between a new and a vintage unit. I am willing to bet too that a lot of the fiberglass insulation in mine is matted, and the new stuff has more R per inch than the old stuff. BTW I haven't noticed in everybody's factory tour pics, but are they using any type of thermal break between the ribs and the interior panels? And are the interior panels still aluminum?

Aaron

[Silvertwinkie]

You know, I thought that they used the same R value since the fiberglass is fiberglass and isn't very high tech, but I suppose that there is a difference if it melts the snow off you unit and you could be right, if matted it would loose a bunch of R value.

When I was at the factory, I saw the shell be built, shell joints inside sealed with some sort of grey looking caulk, the shell mated to the chassis, and then fiberglass followed by alum skin on the inside wall, followed by either that carpeted suff and/or that sponge like plastic stuff (real tech term I know).

Also, if it makes a difference the newer ones (at least the Safari line) seem like the windows have a cold chill or slight breeze that passes through them when cold out and the windows closed....not sure if the Classics are the same.

[Navigator]

Canoe,
Interesting that you mentioned that! A long, long time ago we calculated furlongs-per-fortnight, and it comes suprisingly close to: get this! light-years-per-eon!! Dont take my word for it, check it out. BTW how cold does it get in central MN? I was up there in Oct. to pick up my A/S and the thermostat fritzed on my tow vehicle. Guy in Brooklyn Park charged me $130.- to put in a new thermo. Brr.
Dick

[wahoonc]

Originally posted by Silvertwinkie
You know, I thought that they used the same R value since the fiberglass is fiberglass and isn't very high tech, but I suppose that there is a difference if it melts the snow off you unit and you could be right, if matted it would loose a bunch of R value.

Eric,
They have actually come up with a fiberglass insulation that has better R value than the stuff of 20+ years ago. Just don't recall what the difference is. I just know that the new stuff has a better R per inch value. I would think that any single pane window would give you a chill, you might try putting a thermal tint on it? Some of mine have a mirror tint on it that is great for bouncing the sun, but make it kind of dark on the inside. We use it on a couple of the windows at our house too, it helps keep the heat down on the inside in the summer but I don't think it does too much in the winter going the other way. LOL

Aaron

[Inland RV Center, In]

There have never been any reports of any "snow pile up" damage to any Airstream trailer.

Keep in mind the the trailer is semi-monocouqe construction.

It by leaps and bounds will take more snow weight than any SOB.

With that thought in mind, has anyone ever heard of a brand X having a roof cave in or become damaged by snow?

I never have.

Andy

[InsideOut]

in my case with 4" of snow and an effective length of 29 feet of trailer, the snow load is 1054#

Considering that a 200# person can get up on the roof of an Airstream, as long as their weight is distributed...there shouldn't be any trouble with 1054# of snow/ice on the roof. It's well distributed over the whole top (7'x29'=203sf in your case) whereas a person may be only distributed over 16 sf. (on 4'x4' padded plywood)

200# over 16sf = 12.5# psf
1054# over 203sf = 5.12# psf

I don't think there is a problem...we've never worried about it.

Shari

[Navigator]

I'm not worried about damage to the roof; not by a long shot!
Its the axle load that was the concern.
Anyway I climbed a ladder and swept it off. We are expecting an ice storm tonight.
Dick

[InsideOut]

Its the axle load that was the concern.

If your trailer is just sitting there with a dead load of 1054# on your axles, it's much different (not as big of an issue) than if it's a dynamic load bouncing down the road. Still don't think there is a problem...but better safe than sorry, if you'll sleep better tonight!

Shari

[Davydd]

We are getting about a foot of snow tonight. The thought of it being a problem seems very remote to me. Roof loads in Minnesota buildings by code have to hold 40 lbs per sf. That's a lot of load and I doubt, other than snow drifting, the loads ever reached that in Minnesota. There is no snow drifting on an Airstream roof.

Dick, How cold does it get in Minnesota? I think Embarass Minnesota got down to over -60 a few years ago. I live in a depression about 20 feet lower than our road and one winter I registered -43 when the weather bureau was claiming -32. I couldn't believe it so I went out and bought another thermometer to confirm it. It is going to get very cold later this week. I may have to wear a hat and gloves.

[WayWard Wind]

We live in North Central Minn & the other night it was neg 22, with wind chills to -45. That was inside the house, can't confirm the outside temps. I worked for a natural gas utility & in the 70's it was down to -52, now that was cold. Had to wear a parka inside the truck. While I have the "Little Gem" under a temp cover ( see photo's on another thread) whenever I see a snow load building I remove it, just for peace of mind. Daveydd if you travel North 169 towards Mille Lacs lake on the West side are several bldgs that gave in to snow loads several years ago when we had that mega storm.
Best,

[Silvertwinkie]

Well, the new coaches do have some tinting to them in the glass, so sunlight isn't really a problem, but the single pane does let loose some serious cold stuff!

I didn't know that about fiberglass. Good to know when I do my garage project.

Me, I worry more about bird droppings than 4"-8" of snow. Still I do take some off when I can just so I sleep a bit better at night too!