Gas and Oil Home Heating Furnaces - Propane tankless hot water heater

I'm building a small shop whose hot water requirements will be two sinks and a washing machine. Just me and my wife, so even washing clothes will be minimal, so we dicided to go with a porpane tankless hot water heater.

1.) For the application above, what kind of gallons per minute am I talking about?

2.) I'm building this shop myself. What type of pipe is required for propane?

3.) Originally, we were going to go quick and dirty with a 20 LBS. propane bottle until someone said it's illegal to put one inside the house. Would it be unsafe to have one sitting in the rafters of an open air carport?

4.) Any comparisons anyone wants to make on electric vs propane for this application?

I'm not sure the tank will be large enough to feed the heater. Tankless heaters have a very large draw (gas wise), sometimes larger then a furnace.

2.) I'm building this shop myself. What type of pipe is required for propane?
Depends on local code.
Copper tubing, steel pipe, and CSST are typical materials.

> 3.)Would it be unsafe to have tank sitting in the rafters of an open air carport?
I believe it is not allowed if the valve is open. Btw, propane is heavier than air.


> 4.) Any comparisons anyone wants to make on electric vs propane for this application?
Electric will initially be a lot cheaper than a tankless and will not require ongoing resupply of the energy source.