That’s a great question, and the short answer is quite simple. From a cost of operation point of view, it doesn’t matter if you deliver the electrically-generated heat via water pipes in the floor or electrical heating mats. Your annual heating costs will be the same. That said, there are technical issues you should consider beyond this. Hydronic infloor heating is the term used to describe plastic floor pipes that deliver warm water, heating rooms from the bottom up, and it’s how the heat would be delivered from a boiler. Installing a boiler, floor pipes and control panel for a hydronic heating system will be more expensive and troublesome than electric heating mats, which are really just like an electric blanket installed under finished flooring. On the plus side, hydronic systems do leave your options open to using other energy sources in the future, should electricity become too expensive or unreliable. Depending on where you live, propane is probably a less costly heating option than electricity even right now. In my area propane offers a 20% savings over electricity, assuming you’re running a condensing boiler with an efficiency of 96%. A hydronic system also allows the use of solar-heated water as a supplement to whatever main heat source you’re using.