I'm in the process of moving , and taking my clay mud tub with me. (I have bucketed up 22 5-gallon pails, each with 80 pounds of clay). I'm moving from a place with lots of land (so I just kept it outdoors and covered) to much less land and more neighbors.

I saw at CRC campground, they had a mud pit in a geodesic dome. I was thinking about putting in a greenhouse for the mudpit to allow the sun to heat things up. (I'm in Canada, so getting more heat in there is important). But there is already a small portable shed there I could use.

I thought the greenhouse would heat it up better than the the shed, but now I'm not so sure.

Any thoughts about using a windowless shed (although I could add a fan into a wall to give some circulation for moisture buildup) vs a greenhouse for a mud tub?

Hmmmm...that is a tough call to make 'from the hip'.

I think the greenhouse would get more solar gain...when the sun is shining. But the shed would probably be more insulating at all other times. Beings you mention 'Canada',I'd think the shed might win out a bit - especially considering longer, colder, darker winters. ...and privacy if you want any kind of light which might be noticed by neighbors.

You could obviously 'split the difference' so to speak by putting some sort of solar heater on the shed to pump heat into the mud. Or if maybe fall/winter/spring mud time aren't that important then the greenhouse might win out. But year-round, seems like the shed might be a better option.

Though I will say, for me, this has been an amazing summer sinking in the favorite mud pit as all sorts of stars, meteors, satellites, and other outer-space phenomena buzz overhead. So you might consider a summer mud spot - fully outside and some sort of enclosure for the colder season.

Not being from Canada I don't know what its like where you are in terms of weather, that said I would think a greenhouse would dry up the Mud/Clay so you'd have to keep maintaining it with water to keep it to how you like it, and then you have the issue of what happens if the glass gets damaged and brakes. You run the risk of injury if playing in a tub of mud where there may be small bit of glass.

Shed's might get damaged in weather - However I have seen guys using frames in there gardens and covering them in the same thick plastic as used on polytunnels this might be an option to think of?

I'll private message you the climbing frame link.

Think I'd go with the Greenhouse, though hope you could put it far enough away from the neighbors....
You could always put up some 'tinting' or 'film' on some of the glass panels if you needed to..... And you could always grow some plants and veggies in it !!!

An old dark Shed doesn't sound too attractive........

Hope your move goes well......