Yes but, why?

A 12x13' ft. room will take 15 minutes to coat. And why use shellac, especailly on a large project like flooring?

The product is flammable. The risk of a vapor explosion is high compared to using stains and polyurethanes. All open flames needs to be off.

Shellac is a traditional and beautiful, but not particularly robust, floor finish. One of its great virtues is easy repairability, since one coat of finish melts into the next you can always go back and re-coat or sand off and successfully patch damaged areas, something extraordinarily difficult with more modern finishes. It's a reasonable choice for a no pets, no shoes household. I think you'd use it mainly because it looks so much better than polyurethane, but some like it for its lack of toxicity.

The solvent is usually ethanol, flammable but not highly dangerously so, a few window fans ehausting the air coupled with reasonable precautions against ignition sources should avoid any build up of fumes. To use as a sealer coat there are now water-based formulations (eg from Target Coatings) that would avoid most of the solvent, but the pound cut of those is quite low and it would take a long time to build a finish film.

Also not sure why you wouldn't want to do the whole foor at once. You should be able to put down 4-5 coats a day-- if shellac doesn't dry to the touch (and powder off when sanded) in 10-15 minutes it's not fresh enough. Not sure what the correct applicator is, perhaps a lambswool applicator, or maybe just spray it in that small a room.

Thank you all for the replies. I decided to use shellac for some of the qualities rwiegand mentioned; the aesthetics, repairability, quick drying, and non-toxicity of the shellac itself. Also, for the sake of experimentation. There is another floor of this house that will get poly, but the second floor will get shellac. I've wanted to try shellac on a floor for some time, and have ordered the supplies already.

I am slowly renovating the second floor and as each room is finished individually, I would like to finish its floor and move the furniture back in. I would like to wait and finish the hallway last. I thought the blending ability of shellac could possibly be conducive to this plan? There are two rooms that are perpendicular to the hallway, with the floorboards in them running parallel to the hallway and it’s floorboards. I thought for those, I would finish the floors to the doorways and end cleanly on a floorboard in the doorway—then pick up in the hallway later. There is third room at the end of the hallway, where the floorboards run into it. That section is at the end of the room. I was thinking of finishing the majority of that room, but ending on the last board parallel to the ones that run into the hallway, so about 80% of the room would be done, and complete the end of the room when the hallway gets done. My assumption was that it would be better to finish cleanly on a discrete floorboard, which I’m not sure is true or not. Could I potentially just finish that entire third room and end the shellac across the doorway perpendicular to the floorboards running into the hallway? So that the finish runs across the few feet of boards? Would coming back later, sanding into where I left off and continuing down the hallway work? It seems like the pick-up point might be more noticeable there, across those feet feet of boards, if the blending didn’t work. Overall, I’m wondering how easy or hard it is to stop and start with shellac and have the finish look continuous. I actually should be experimenting on scrap wood, which I will do this week.

Stopping at a clean transition, like a doorway, works fine, even for modern finishes. As you are going to need multiple coats you can vary the transition point several inches or boards to minimize the overlap effect. I've never done a floor in shellac, but use it a lot on furniture. I'm guessing a floor will take 4-5 coats, 3 at an absolute minimum. .

OK, great to know--thank you!