I want Thermopex or Logstor or whatever the really good stuff is. I want 1-1/4" PEX version or 1" PAP. The problem I'm running into is purchasing the stuff. I can't find anyone that wants to sell me less than 100' when I only need about 30' of it. Buying from a far away dealer means shipping prices are ridiculous.
At my last house, I ran the dual lines myself, lined the trench with plastic, and spray foamed them in place with closed cell foam. Over 3 seasons, I never had a degree of temp loss between house and boiler on a 80' run. I could do the same here. I'd rather have my lines encased in something better than sheet plastic this time though, and drain tile is not much better, to say the least. I'd love to run lines inside of 6" PVC and spray foam them in there, but it seems difficult to be able to spray foam lines inside of any pipe, really.
Anyone has wisdom to add? Absolute worst case, I'll buy 100' of the stuff and sell what I don't use or keep for when I build a big garage later down the road.