Also how big of a chore is it to install gas lines in a house that never had them?
Well, you got lots of answers on the other stuff but I didn't see this addressed too well.
A lot of how easy it will be depends on whether your house is on a slab or over a basement/crawl space. Obviously, a basement or crawl space will make it a lot easier than a slab. I've never done work on a slab so unless you can get a pipe to each appliance through an outside wall I don't have any clue as to whether you can go up into an attic and then back down....
I'm far from being an expert here but many years of building custom homes and having piped both our old house and the one we now live in have given me some experience.
The first thing I'd do is talk to the local propane folks about what is involved with the installation and also talk to your local building inspector. Some areas require new installation to be permitted and/or inspected. Some even require every change to be permitted and/or inspected although that is usually in big cities only. Don't cut corners with permits or inspections as you would be far from the first person who had an insurance claim denied or who got criminally charged if someone got hurt as a result of an improper installation.
With all that said, the installation will generally involve some combination of rigid pipe, corrugated stainless steel tubing (CSST) or copper lines. Again, your local supplier or code enforcement folks will know if any of those are preferred or prohibited. Some LP supplies have a chemical makeup that is corrosive to some piping material, some is considered "dirty" and may require in-line filters and some may be considered "wet". And you may need drip/debris legs at each appliance location. Pay particular attention to the hot water heater as they generally require a drip/debris leg.
Pay particular attention to whatever grounding requirements your type of installation and material choice requires. For instance some CSST requires a bare 6 gauge copper wire run to the building's main electrical ground. Some installations require a completely separate grounding system. Local codes can seem pretty screwy but that's the world we live in.
It might be helpful to look at the back of a few ranges and dryers at you local appliance outlet so you can get an idea of where the gas inlets are and where the gas line can be brought out of the floor/wall and land in the hollow space on the rear of the range. If you already have the appliance or know what you will buy it makes siting the stub-out easier.
CSST often requires a few special tools and the fittings used must be from the same manufacturer as the tubing. It's pricey but fast. Copper and steel pipe are also well within the ability of the average handyman to run especially if you have a pipe threader. It is worth noting that some jurisdictions require any pipe exposed in a room to be steel pipe due to the chance of damage.
I know I didn't cover everything you need to know and also hope I didn't scare you away. I suspect that if you're on a site like this you can most likely handle this project yourself (with a little advice).
Lance
