Hi mongo- Thanks for your thoughts. I agree that the small pump and loop would be best, but I think too difficult at this point. Here's the situation: bathroom is over a VERY shallow crawl space (used to be about 5" between joist and dirt, but when we gutted the space my DH spent many sweaty days shoveling the CLAY soil out through a hole we cut in the wall. Ugh!) The only access to underneath the floor would be if we removed the tub and cut out the subfloor. Even then, there's only about 18-24" under there. The supply used to run in the exterior walls, and froze last winter. We (DH) rerouted the supply through the attic space (one story home). He ran it right along the sheetrock, and insulated the cold lines with that grey split stuff against summer condensation. Then he created a sort of "tent" or "tunnel" over both sets of pipes with that aluminum faced bubble-wrap type of insulation. All foamed tightly in place. On top of that is two layers of pink finerglass batt. It's certainly better insulated than it was before. Pipe is 3/4" PEX. At the interior bathroom wall, it turns down to supply shut-off valves accessible in the bathtub control panel. From there it runs under the bathroom floor, on the warm side of rigid insulation foamed tightly to the joists. I actually just got off the phone with a tech guy from one of the tankless on-demand companies. He says that the tankless option is do-able, but we'd need such an upgraded model that it wouldn't be worth it for the 30 seconds or so we'd save waiting. The only place to put it would be in the closet by the shut-offs (since that's the closest access we have). And since there's no way to add it to the sink-only plumbing (I don;t think: see below) it would have to be sized for the GPM the shower demands, otherwise even when it's not heating the water, since the hot water is running through it, it would reduce the flow at the shower too much. Since we have a showerhead AND handshower that sometimes run simultaneously, that would not do. And the higher GPM models are just too pricey. I was thinking I *might* be able to swing $125 or so by next fall if I saved. not $500 certainly. Our bath remodel and some medical emergencies have really drained us, I'm nervous about even buying fuel oil for the rest of the winter! The only space and access at the vanity itself is a 4" space between the wall and the back of the drawers. The vanity is all drawers, and was custom made, so we can't/won't modify it. I don't imagine any of the cheap heaters are like 3" deep? So, I will probably have to learn to live with it. Not a huge big deal. The shower and tub take very little time to warm up (higher GPM I guess) so its really the sinks that are the issue. We'll probably just live with it. Thanks!

The tile should finally be in on Monday and installation will begin. Hooray! We've been concentrating so much on the kitchen, that we're a bit overdue to choose a bathroom vanity. The plans call for a toe kick heater. My question is whether we need to purchase a vanity cabinet that has a toe kick or if we can use one with feet. Our choices are limited for the size we need (preferably under 30 inches) with a toe kick built-in. Thanks. (I'll cross post on the heating/air conditioning forum.)

Is there a basement or crawl space underneath the kitchen floor? If yes then you may be able to install a radiant heat system. It would tap into your current hot water heating system. The other option is to replace the cast iron radiator with a base board radiator. It would free up some wall space. There are manufacturers which make radiators which are very stylish looking in various colors and shapes. Perhaps you can mount the new radiator high on the wall so you could use the space below it. It is not optimum, but it could work in your situation. I think you can also get a toe kick size radiator, but I am not sure if these are effective. Use electric resistance heating is an option, but it is going to be much more expensive to operate compared to the gas furnace. This would be the least attractive option for me.

Make sure it is not hard to replace the switch. Resistive heater loads pull more current till they warm up (as do light bulbs, but they heat faster) and being even close to the contact rating can result in shorter life.