The toilet closet flange is far more common as a source for a leak, but if the tub was not properly installed, the drain could be leaking. See if there is an access door behind the tub faucet and drain assembly. If anything is wet, it needs to be repaired. If the house is less than a year old it must be repaired under warranty. Sometimes you have to open ceilings or walls to make repairs.
If it's coming from the roof then the bathroom ceiling will have a water stain on it too. If you don't see this then it is coming from your bathroom.
I would paint the ceiling white, especially since the bathroom is small. If you are using a deep red color, it could make the bathroom appear even smaller, and painting the ceiling red could make you feel boxed in. A while ceiling will help to create a more open feeling.
The best lighting for a bathroom ceiling is a hanging light fixture with more than one bulb. You don't want all of the light in your bathroom to come from a single bulb.
Do any brands have home lighting ceiling fan fixtures that would work in a bathroom?
Normally the second switch in a bathroom is the control for the bathroom's exhaust fan. The exhaust fan removes bad odors and humidity from the bathroom, and is on the ceiling of the bathroom.
You can check in local stores. I personally prefer buying lights on-line - there are many on-line stores that sell light covers (also bathroom ceiling fan light), such as Amazon, Wallmart, eBay and so on. If you don't find it under the keyword you used (bathroom fan light cover), you can try searching for "bathroom ceiling fan light cover" or simply "ceiling fan light cover" (and then find suitable one for your bathroom). In case you have a special ceiling fan, you may need to contact the producer of ceiling fans for suitable light covers.
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is mirrored ceiling acceptable in a bathroom
IKEA offers a variety of bathroom lights, including ceiling lights, wall lights, mirror lights, and cabinet lights. They come in different styles, such as modern, traditional, and minimalist, to suit different preferences and bathroom designs.
ET2 Lighting has a wide selection of bathroom lighting fixtures. Whether you are looking for Ceiling Lights and fixtures, or Bathroom Vanity Lighting, they have a selection for every bathroom style.
Newly constructed homes are often built without ceiling lights in some rooms or with limited ceiling lights. A modern floor lamp can be a necessity for an otherwise dark room in this type of home.
It is possible steam from the shower or bath is condensing on the ceiling and causing discoloration.