It may be right for the volume of bathroom if enclosed but it is not so you are looking at a bigger volume. To options spring to mind. A bigger exhaust in current location or a dan to blow the air into bathroom but that may make you cold. In the meantime by some damprid from the hardware to absorb moisture in the wir and maybe shorter cooler showers?

Air (hot, damp, cold) will move to equalise within the boundaries it has. You need to limit the boundaries ie add a door. Or force the air via mechanical means to be elsewhere. So as above more fans. Or run a dehumidifier in the WIR.

Thank you for the feedback and ideas. Any suggestions for what sort of fan would be appropriate to blow the air back into thr bathroom? I presume it would need to blow the air in one direction, rather than a fan that goes around and around?

Adding a door would be a big decision for us, as we deliberately designed the room to be more open to seamlessly flow in to the robe (but so does the steam, ha ha!) I wonder what the likelihood of a door fixing the issue would be? I would want to be confident before we invest in putting in a door.

I would install a door between the bathroom and WIR. We have the same set up. An ensuite open to the WIR. An exhaust fan in our walk in shower space, no shower door. However, we have a sliding door between WIR and bedroom. This stops steam, light, noise from getting into the bedroom. We designed it this way, as my husband is up at 5am. He can shower etc without disturbing myself in the bedroom. A door would solve your problem if positioned between WIR and ensuite. We are in Perth, WA so our winters are short and steam is not an all year problem.

And don’t have the window open while running the exhaust. Leave the window open after the fan is off to help circulate air while the shower is still wet.

I thought you had to leave the window open while the fan is running to draw fresh air in to the room so it’s easier to draw air into the room and have the fan expel the steam?

You will have enough airflow from the open plan arrangement. Try the showers with the window shut and also opened just a crack and see what happens. Any air blowing in the window will be blowing the hot damp air out into the bedroom.

Agree, keep the window shut while showering with exhaust fan on. When the fan is off, open the window.

"I thought you had to leave the window open while the fan is running to draw fresh air in to the room so it’s easier to draw air into the room and have the fan expel the steam?"

You need to have more air coming in from somewhere to replace the air the fan is exhausting, but it doesn't need to be from a window, indeed as Kate said the cold air from outside can make condensation worse. People notice poor performance when they close the window and the door, but you don't have a door.

You haven't put a plan of your bathroom/wiw/bedroom. When we moved into our house, our ensuite was very open to our bedroom (and no doors from bedroom to wiw, and ensuite to wiw). We enclosed the ensuite so that we could heat it separately in winter but with a large fixed panel of glass so we could still see our lovely view out our bedroom windows. We got our shower screen maker to make us a glass door for between the bedroom and ensuite - no frame, just 2 hinges like a frameless shower door. I really like the effect. Depends if your design suits a sliding door or a hinged door.

"I thought you had to leave the window open while the fan is running to draw fresh air in to the room so it’s easier to draw air into the room and have the fan expel the steam?"

You need to have more air coming in from somewhere to replace the air the fan is exhausting, but it doesn't need to be from a window, indeed as Kate said the cold air from outside can make condensation worse. People notice poor performance when they close the window and the door, but you don't have a door.

I realised my last line could cause confusion. People notice poor performance of the exhaust fan when they close both the window and the door because the motor strains to suck air. You can hear it. That's why it is advised to 'leave the window open'. Or the door. One or the other as long as there is a source of incoming air to compensate for the amount of air being sucked out. My point was you don't need to open the window because having no door you have a source of incoming air.

The poor performance of your bathroom exhaust is different to that. You have no door. It's not a lack of incoming air. If anything, it is too much air, possibly blowing around too much, possibly too cold.

Reading over your description again, you have a skylight over the shower too. Is it covered at ceiling level or only at the top? Does it open or have any type of vent? I'm not that familiar with skylights, but if it is over the shower and is designed well it should be helping should it not? I hope it isn't another trendy design feature, like the doorless ensuites, which is causing problems.

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