Need to run insulated hot water 60 ft from boiler to oil boiler. What is the cheapest way

I am installing my Econoburn in my boiler room 10 ft from house. I bought my own pex and Home Depot sells 4" flex drain tubing without slits for around $55 for 100'. I am injecting foam into the 4" with the pex inside . looks similar to the $4.00 a foot stuff they sell for about a third the cost.

I am using the foam in a can started with the white but am probably going to switch to the blue. Runs around $5. a can and takes a little over 1 can per 10 ft.The pex is wrapped in the blue foam sill plate first and I made some cardboard spacers to keep the pex in the center of the larger pipe. I have some 3/8 vinyl tubing that is taped to the foam can and then inserted about halfway into the 4" tube. I start foaming and pull the tubing out as I apply the foam. Clean the 3/8 tubing right away or it will be useless. Good luck!

I don't think you need the foam injected (great idea though) since you are above ground. Price 1 1/4 PEX and 1 1/4 Copper then decide (1 1/4 copper is from a plumbing supply, not a box store usually, and is in 20 foot lengths). Then your can insulate to your hearts content: I used AC duct wrap. You could also use fiberglass (get the roll, not batt) then tape it closed. 80 feet of copper was loosing about 30-50K BTU in my basement before insulating. Works much better insulated!