Would love photos if you’ve done a similar project! Thank you.

How wide is your powder room? You may not have enough clearance in front of the toilet if you rotate it. I think around 50 in. is pretty the minimum.

They sell toilet tank lids that have sinks built in to them. Not sure if it would fit that particular toilet though. I saw it at HomeDepot.

It's too narrow to turn the toilet as you need 24" minimum clear space in front of the toilet, and you need 15" of clear space on either side of the center line of the toilet. The toilet has a 12" rough-in. There is no way to make that work from a code perspective, and it would be horribly crowded if you ignored code and did it without getting a permit. There are also requirements about spacing of other fixtures, like sinks.

Post a floor plan with dimensions so we can see if there is any way to do this....

I don’t have the dimensions but will get them (just bought the house). It’s not as narrow as many I have seen. What about those tiny wall mounted powder room sinks? Is the sewer access point the issue?

The issue with adding a sink is that it not only needs to be connected to the sewer, but it needs to be connected to the vent stack...a piping system that exits through the roof. The sink vent can be tied in to the toilet vent, but that will mean opening up the walls and maybe the ceiling.

Thank you kudzu9. I’m a total novice so this is helpful a this is always the case? There is significant plumbing in the basement between the laundry room right next to this room and then the toilet. I didn’t realize you needed to go through the ceiling!

The vent stack that is already part of the house goes through the roof somewhere (and there may be more than one, depending on the layout of your house). Every toilet/shower/sink/bathtub is required to be connected to the vent system. If you put in a sink, you need to tie in to the vent stack, which might be in the wall already and is certainly in one of the walls near the toilet. When I said "maybe the ceiling" it was just to alert you to the fact that there are several ways to get to a vent stack; for example, sometimes it's through the walls and sometimes it's up a wall and across a ceiling, etc. It all depends on what piping is already in the nearby walls and where it is in relation to what you want to install.

Looking more closely at your photo, I see there is a cleanout plug at floor level on the left, and a large pipe going up inside the wall, so that is part of what you'll tap in to.

The bottomline is this:

1. You can't turn the toilet sideways so I suspect it's got to stay exactly where it is.

2. If you put in a sink, it will need two connections: the sewer and the vent, and you also need to figure out where the hot and cold water will come from.

3. You need to have adequate clearance around and between the toilet and the sink, which is determined by code requirements. I can't tell whether that can be done in your space, because I don't know the full layout or how big it is.

4. You're going to have to open up at least one wall for the sink plumbing, and possibly go into the floor (which is concrete?).

5. You need a professional to look at this and tell you what is possible.

The kind of tank cover that zannej mentioned is sometimes sold for water conservation, because it may use the wash water for the next flush. If the tank is already full, the excess goes into the bowl via the tank overflow tube, so it's important that the overflow tube be functioning.

An advantage, but also a drawback, is that this type is plumbed only to cold water. On one hand, it means that it can tie into the same cold-water line that feeds the tank. On the other, it means that it's plumbed only to cold water.

There are various combo units manufactured. Most are side-by-side but here is one where the sink is above the tank. It appears that it could be connected to both cold and hot water, if there is a practical way to extend hot water to the room.

From your photo, it appears that there might be doors on both sides of the room. If there are, do you need both of them? Eliminating one might give other space for a sink, if the considerations about drain, vent stack, and water source can all be met.

Thank you SO much! I figured I would need to open the floor and wall, will be hiring a plumber and contractor. This toilet sink combo is very interesting! Do you know the brand, @Paul? Only one door on the room unfortunately. It’s under the stairs and in front of a root cellar.