Snow Load on a TM?

[centerisl-TMO]

I ended up on this forum when @larsdennert posted about towing a TM with his Rivian on the Rivian forum - and then posted here. I've read quite a few threads, in particular the one about winter camping in Utah that featured below freezing temps and some snow.

My first question is - what kind of snow load _might_ be supported on a 10-15 year old TM? There is a TM on CL that was "Damaged/crushed by packed snow on roof" - not interested in that trailer (or a project) but was wondering what might be a safe load a) when closed and b) when open. 6" of powder is of course a lot lighter than compact snow and then rain - but is there a sense of what might be a reasonable working load closed - and open?

 

[Wavery]

TMs really aren't built to camp in the snow. We've had 4" of packed snow while camping. I wouldn't recommend any more than that with the trailer open.

The biggest issue is trying to close the trailer with snow on the roof. The rear shell isn't tooooooo bad. It can be closed with a little snow on the roof but be prepared to assist the roof in lowering because that extra weight will make that roof come down hard. Once the rear roof is down, it must be cleared of snow so that the front roof can be lowered.

It's really hard to remove the snow from the front roof unless you have a ladder. With the rear roof down, the front roof is very unstable and that may be where the above pictured trailer collapsed. It's best to remove as much snow as possible from the front roof BEFORE lowering the rear roof so the rear roof can offer some stability to the front roof.

When you lower the front roof, it will need a lot of support (2-3 people) to keep that roof from slamming down. The combination of the snow weight and the roof air conditioner, slamming down can make the roof buckle in the middle, destroying the roof.

 

[Shane826]

I’ve attached a screenshot from page 40 of the TrailManor owners manual. However, I don’t know if I would let anywhere near that much snow accumulate on the roof.

https://trailmanor.com/wp-content/uploads/2020/01/trailmanor-classic-owners-manual-v091119.pdf

 

[Bill]

Wavery and Shane are right. Snow build-up is dangerous, the the TM is limited in its ability to support it.

If you envision taking the TM into snow country, you should consider getting a snow rake. It isn't really a rake (with teeth). It is more like a scraper, with a flat blade across the end. It has a long aluminum handle with a bend 2/3 of the way up. You stand on the ground outside the trailer, lift the blade up above the snow, then drop the blade gently into the snow and pull it toward you, pulling the snow off the roof. This is a lot easier when the snow is dry and light. Don't let the snow get wet! This is about the only reasonable way to get rid of snow on roof, especially if you have to do it while the TM is open. It is much better than a stepladder and conventional snow shovel, an approach to be avoided.

Bill

 

[centerisl-TMO]

Thank you @Waverly, @Shane826, and Bill - that was very helpful and confirmed what I suspected - for an OPEN TM. Any thoughts on acceptable loads on a closed TM? One of the places I am considering for this TM is some property I have in Cle Elum - here is an image from yesterday.

 

[Bill]

...confirmed what I suspected - for an OPEN TM. Any thoughts on acceptable loads on a closed TM?

I don't have a solid answer. But I suspect that the snow load capacity is not radically different open or closed. My concern is not so much about support at the edges of the shell, but for the strength of the arch of each shell. Remember, the arch of the front shell supports the front roof structure plus the air conditioner, plus any snow load. The arch of the rear shell has to support the rear roof structure, of course, plus its snow load. And if the arch of the front roof starts to squeeze down, it adds to the load that the arch of the rear roof has to support. If either arch starts to deform, you have a major problem.

Would you ever expect to get more than a foot of dry snow in Cle Elum? Would you ever expect to get rain on top of existing snow? Will you have ready access to the site if weather looks bad?

Your photo looks a lot like the evergreen forests of interior Maine, where I grew up. We always expected to see some relatively small tree branches drop onto the roof of the house or camp, which was OK. But it was also common to see a mass of snow accumulate up in the branches, and then suddenly come loose and drop with a big WHOOMP onto the roof below. The impact of, say, 20-40 pounds of dry snow, dropping from a height of maybe 20 feet, could be substantial. If the TM roof is already deep in snow, it might not be good.

Again I don't know, but I have often wondered if you could install a stiff vertical support inside the TM, beneath the forward edge of the rear shell - or perhaps under both shells. You shouldn't bring the load directly onto the center of the floor, so you would want to spread it out toward the edges of the floor somehow. Remember, I have not done this, so I am not suggesting it. Just noodling around ...

Bill

 

[Bill]

Incidentally, a number of TM owners have wanted to carry kayaks on the roof of their TM. Rather than carrying the boats directly on the surface of the roof, many have spanned the roof with a pipe or bar frame, bringing the weight to the edges of the roof. This seems to work. Perhaps you could use this same approach to install a platform of some kind above the roof.

Bill

 

[centerisl-TMO]

Perhaps you could use this same approach to install a platform of some kind above the roof.

That makes sense. In my particular scenario, I suspect that building a structure over the TM would be the better route. Of course then I have to deal with the CCC&Rs but then I'd have something of potential value rather than a temporary hack.

 

[centerisl-TMO]

My concern is not so much about support at the edges of the shell, but for the strength of the arch of each shell.

Indeed - that is indeed worth considering. And yes - there are trees to consider. While the site I posted above might not be catastrophic, my other parcel is more heavily treed. In fact that fallen tree in the foreground turned out to just be a large branch from above! I limbed most of the major branches so my game cam can see the driveway but it was a big one.

 

[Shane826]

Incidentally, a number of TM owners have wanted to carry kayaks on the roof of their TM. Rather than carrying the boats directly on the surface of the roof, many have spanned the roof with a pipe or bar frame, bringing the weight to the edges of the roof. This seems to work. Perhaps you could use this same approach to install a platform of some kind above the roof.

Bill

More incidentally, TM now offers a Sport package on the 2518 & 2720. Part of the package is a kayak rack. They built it as part of the edge frame structure, it doesn’t touch the actual roof surface.

And Bill is spot on… The roof crown is what we worry about. Once you lose that crown it’s all done, no real way of fixing it. I have a parts TM that was donated because it was left out over the winter in NJ and the snow caved the roof. Granted I don’t think this TM was in the best shape to begin with, but…

 

[centerisl-TMO]

he roof crown is what we worry about. Once you lose that crown it’s all done, no real way of fixing it.

"God Save the King/Queen (Crown)!" Got it!

 

[larsdennert]

The 2002 and earlier models are wood roof spar and the later ones are aluminum spar. Having had both in my possession (2002 and 2003) it's a noticeable difference in structural strength. The later versions are pretty robust.