How do you keep your basement warm?

Did you try this and fail? It seems like with the right fan and vent setup (close to the stove) it would work.

Look at recent Woodstock progress hybrid install threads....one has a blower very successfully sending air to the lower level in an upside down home.

Freezing pipes are in issue primarily with pipes built into exterior walls and basements partially or wholly above grade. If either apply then you need to take action.

My old stone uninsulated unheated basement never gets much below 55F even in the dead of winter. the key is few windows and walls dug down below the frost line.

Cut insulation to fit in the basement window cavity. I did that for my mother years ago. her basement was considerably warmer after that. I used 4" paper backed fiberglass, in the spring take it out of the window and in the fall put them back, they lasted for years before she sold the house and moved into a condo. Insulate the pipes.

My full basement is primarily below ground, so part of it is below the frost line. 18 inches to 2 feet max above ground, four small windows and 2 sets of Bilko doors, with wood doors to the basement at the bottom of the Bilko steps. My basement doesn't freeze either, but I suspct it gets below 55. I should put a thermometer down there and see. It stays about 60 in the summer...nice naturally air conditioned area.

55 is the usual below ground constant temp, so you probably have it pegged right

I feel your pain. We've been in this house for a year and are still working out the kinks on figuring out how everything is put together down in the basement. Three zone baseboard heating, hot and cold water, well tank, all the heating pipes from the original house that aren't in use, solar hot water feeding a tankless water heater...blah blah blah. I'm also pretty sure the previous owner just ran around putting up random wires for no reason at all. It's a dang mess that we are systematically figuring out and changing systems to more efficient ones. At least all that copper is with some pretty good money

If you have a variable speed fan on you furnace or even a multi-stage fan, just turn in on and leave the heat off. That should circulate heat from the upstairs to your downstairs. That should be more than enough to keep the pipes from freezing. Should be cheap too. Most furnaces allow for manual overrides that allow you to set slower fan speeds. Just a thought.

Sadly I have forced hot water baseboard heat so this won't work for me. I like some of the other ideas discussed here maybe I will try some before I cut a hole in my floor. You can only cut open the floor once.

No furnace in our house and I can't explain how awesome it is Now that I don't have a furnace I realize how noisy they are. I sleep a ton better without it. We have radiant heat which I would rather not use. I have it set to 55 down there right now. When it gets cold again I plan on trying to use the fan right by the staircase (ceiling fan) to pull the air down like someone suggested.