Hexayurt question

[berkeleyjake]

Can the inner side of a hexayurt be painted or designed without losing the functionality and purpose of the insulation?

[otakup0pe]

Pretty sure you can paint the inside of a RMAX hexayurt no problem. The shiny bit is kind of important on the outside though.

[Canoe]

• Technically,
  there would be minor loss of it's ability to reject heat as the inner surface is also a radiant barrier.
  • The outside surface radiant barrier reflects a large part, but not all, of the heat away. Heat also conducts through the outside radiant barrier, absorbed from hot air against it.
  • The heat that gets past the radiant barrier then has to go through the insulation, which impedes/delays the transfer of that absorbed heat.
  • The heat the reaches the backside of the inner radiant barrier then transfers that heat to the interior two ways:
    - conduction to the air against its surface, and
    - by radiating that heat into the interior.
  • The more shiny the inside foil surface, the more it inhibits the radiation of that heat. For example, if the surface has a reflectance of 84%, then it has an emittance of 1 - .84, or 16%. So while the inner surface can be come warm to the touch, and even hot for panels in the sun, unlike a black painted surface, or even a white painted surface, if you hold your hand a few inches away from the panel you only feel minimal heat radiated off of the panel. This impedes/delays that heat heating up the interior. That heat is given off slowly, which can be beneficial at night.
    (that heat still conducts to the inside air that touches the panel)
  • So if you paint it, or have decorations against it, that will allow more heat to radiate from the panel into the interior. Panels in the sun matter more.
  • The above should only matter if you're trying to maximize the passive performance of your yurt.
    - If this is you, then you'll want to use a solvent to remove any branding paint on the foil surface.
• Practically,
  • A painted inner surface (or decorations touching the surface; air-gap keeps the radiant barrier performance) effect should be minor.
  • As the day/night cycles between its min and max temperatures, you may find that the yurt heats up somewhat faster and gets somewhat hotter inside, and on cool nights, the heat bodies give off would not be reflected back at those sleeping. Most years most people don't notice an effect, and those that do notice an effect report it is minor.
  • A very small/rare minority have complained that their yurt with interior paint heats up faster with the morning sun taking some of the sleep-in time away or - more typically - making it a tiny bit more warm than they'd like. In some of these complaints, it is noted that the quality of yurt construction is less than ideal, with gaps between panels that let heat in (although sealed with packing tape, that doesn't have radiant nor meaningful insulating properties) and/or big gaps in their door, letting hot dusty air in.
• If you have a DIY swamp-cooler to provide cooled fresh air to the inside of the yurt, that can easily overcome any difference and is a low cost reliable way to ensure comfort for sleeping or rest on the playa.

[Canoe]

The shiny outside reflecting the sun's heat can end up radiating at neighbours and baking them.
Some people take a can of white gloss spray paint so they can lightly mist a shiny outside surface if it's nuking their neighbours.

[Captain Goddammit]

Its got nuthin' to do with hexayurts but that reminded me... sometimes I drive a horse hauling truck, with a trailer that is all smooth polished stainless. It's a giant mirror... people hate driving behind it at night! But they do remember to dim their lights.