I never heard of it before either. Doesn't seem to be uniquely Nuage, but the fact that they want to do this to a sweatlodge fits pretty well with their putting a price tag on evetrything.
http://www.evans-graphics.co.uk/resin.htmlhttp://www.deco-coat.com/doming.html"Doming Systems form a crystal clear, high gloss dome or lens effect on decals, photos, labels, key fobs, magnets, lapel pins, medallions, name plates, signs, etc.... Their high gloss finish and outstanding clarity will enhance any image it is applied over. Deco-Coat Doming Resins protect and add value to your product."
Seems to be normally done on smaller objects. Might not even work on a lodge. And if it does a resin coating will raise the temperature, make it more likely people will get burned or scalded.
Other meanings I found don't make any sense in this context, Freemasons using the word to mean courage, Marxists using it to mean demanding worker central control, and S & M people using it to mean a Dominant's power over a Submissive.
I did find this on a Christian site.
http://miriams-well.org/healing+prayer/EMLsPPPrayers.html"Release a special Shaft of Light over us for Brotherhood, Love, Harmony and Glory. We hold our loved ones close, to be held and to hold their gains. Thou dost always say yes, Father. Let the Light in this special Shaft doming us, spread forth as a beneficent cloud, healing darkness as it goes until it adds to all Glory over earth, erasing, holding."