Help with LP pipe size and type

[CJCar]

Hi all,

I need some help with LP piping sizing/capacity planning. We bought our house 2 1/2 years ago and it had a rented LP tank and heaters (detailed below). I purchased the tank and all accessories after a nightmare of dealing with the provider. I have removed all of the LP appliances due to age/condition/efficiency. I'm now in the planning stages re-piping the whole thing from the tank on. The existing pipe needs replaced due to excavation work.

My main questions:
What size and type of pipe. I assume yellow PE pipe for the underground? Can this be used inside as well?
Secondary regulator size? Given a known BTU load, how do I find what regulator I need?
Given my load detailed below, how many regulators (and where) would I need?
Is there a fitting that would allow me to connect a regulator/hose from a standard bbq grill to?

Here's what we have/had
500 Gallon in ground tank

• Primary regulator at tank (2PSI ?)
  Copper pipe (1/2") Tee'd underground with runs to house (100') and detached garage (40').​

House (full basement, 1 1/2 story log cabin)

• 
  
  Secondary regulator (copper pipe Tee'd after)
  Vented wall heater (40k BTU?) in basement
  Vented log set in full masonry fireplace on first floor​

Detached garage with 2nd floor apartment

• Meter and Secondary regulator (copper pipe Tee'd after)
  Vented wall heater (40k BTU?) in apartment
  Vented wall heater (15k BTU?) in garage​

This is the goal
House

• 
  
  Stove/Range (currently electric)
  Outdoor Kitchen (all of these are setup to run off a 20lb tank - all could be used at the same time)
  ​

• 
  
  2 Burner Camp Stove (60k BTU)
  2 Burner Cooktop (30k BTU)
  Griddle (60k BTU)​

Generator (currently have a old 6500w Onan, would like to plan for a 12kw in future)
Hookup for portable LP vent free heater in basement (emergency use only)​

Garage/Apartment

• Hookup for portable LP vent free heater in both (emergency use only)​

Thank you in advance for any input!

 

[Firebrick43]

Most just use copper tubing underground. I don't believe PE can be used inside for any fuels, but there may be some where that allows it. You need to decide what pressures you are going to run. Most systems are 11 inches of water column( about 1/2 psi) but some newer systems are running 2 psi. Big difference in pipe sizes.

Second, everything you mention is pretty easy to provide for if under 80' (past second regulator) even on a low pressure 11WC system with 1" black iron, except the genny.

It would behoove you to try and place the generator as close as possible to the secondary regulator, not at the end of the run, and even better would for it to have its own secondary(maybe even its own primary) and run at 2 psi on the secondary.