Ours doesn't have a window either (and it never occurred to me that people think this is a problem). We put a lot of art on the walls and went with a bright shower curtain and bright accessories. If you can't paint in your rental, bright art goes a long way.

If you have wall space, add a large mirror that will reflect light from the light fixture. I would also go with a white shower curtain and if your landlord allows it, paint the bathroom a light color.

Without a picture, it's hard to give you that much advice. Can you paint? What colors are already in there? Bright yellow and pale aqua are great colors to make a room feel bright and open. If you can't paint, there are lots of places to find shower curtains, rugs, and other accessories. Also, IKEA sells a LOT of pretty bathroom lighting for really affordable prices. Hope that helps! If I could see a picture I'd be able to tell you more.

The bathroom in my favorite coffee house is windowless, and they have salvaged windows hanging on the walls with white Christmas lights around and behind them. It wouldn't work in every house, for sure, but it's lovely in there.

Amazingly enough, most bathrooms don't have windows....
....but they do have electrical lighting.

Just make sure that your electrical lighting fixtures meet your needs not only to light the room but to illuminate your face when you're doing your makeup, etc. Appropriate wattage bulbs make all the difference in the world.

Extra mirrors are helpful to bounce light around, and light paint (pale blue or pale green feel clean) will help. I think white will make it look like you are trying to compensate for the lack of natural light and that will only underscore it. Try not to have just overhead light -- add sconces if you can on either side of the main mirror. Bright white fluffy towels and a shower curtain and perhaps a teak bath mat will give it as clean and airy a feel as can be managed without a window...
pam h
howtorunyourlife.blogspot.com

I also have an interior bathroom. I actually painted it dark gray and then added large, mostly white (with a pop of red) artwork and white towels. With the white tub, light gray tile, large mirror, and light granite counter top, I think the place looks pretty classy, if I do say so myself. That being said, this is the second bathroom, so I don't know if I'd want to put my makeup on in there every day. However, I always get compliments from guests who use it as a powder room.

Fresh white paint, white bath textiles, extra mirrors, candles.

We had this problem when we moved into a big loft with an interior closed bathroom and dark, distressed concrete floors. I don't know how much freedom you have to design (rental or owned) but we did these things:

1. Mounted "cloud" style fluorescent light fixtures horizontally along the WALLS - at eye level. Converted overhead lighting into cloud fixtures too - bright, softly diffused light from above AND at eye level made it seem like a bright sunny day in there. Cloud lights rock.

2. Removed the medicine cabinet over the sink, and replaced with a huge sheet of unframed mirror.

3. Kept clutter at zero. The more space, the bigger & brighter it was.

4. White paint, white towels, white shower curtain, and white fixtures are your friends.

3.

I think most bathrooms do have windows.

However, I think they all should. That room needs fresh air.

Mirrors, or rather a large single mirror. Think hotel bath, where the wall mirror extends over the sink and toilet.

And a multi light fixture. At least 150 watts of light.

No kidding, when I moved, my no window bath has 1,050 watts of lights. It was blinding. I reduced that to 240 watts, and painted the bath white.

What kind of art could you put in your bathroom that wouldn't be damaged by the high humidity?

@just_kazari - it depends on how large your bathroom is and how much humidity you generate, but we only have relatively inexpensive prints in our bathroom, not large expensive works or things that are overly sentimental.

@Pi that's what I figured :) I was just wondering if things like oils or photographs would stand up, but I suppose not, huh?

Also -- any worries about frames?

Our last rental had a windowless bathroom. It was painted a buttery yellow and the minute you turned on the light, it was a cheery sunny-feeling space where you neither felt the yellow, nor noticed the lack of sunlight. I learned a lesson there, personally, it would be the exception to my beloved white but if faced with a windowless room, I would do what that house had over white ("Full Sun" by Kelly Moore is the type of color I'm referring to).

@Village: What a good point about hotel bathrooms and mirrors, never noticed they are always windowless!

@just_kazari - we didn't worry too much about frames. Standard ones are just fine for us. Anything directly exposed to the humidity is probably going to be a problem, so if it's framed that should protect it some, but I wouldn't put oils or any other canvas art. Photographs are fine, but like I said up top, we didn't put anything sentimental or truly one of a kind in there.

I had a similar bathroom with no windows (and really small) that the previous owners had done a great job with. I added accents that helped with the sense of light.

1. Mirror: There was a large mirror along the back wall (farthest from the door, not over the sink). Really opened up the space. Mine was a flat mirror attached to the wall all the way from the half-tiled wall up to the ceiling. If you are renting, or just want an easy installation, han and can't install a wall mirror, hang a framed mirror - as large as the space allows. (See if you can find one framed in chrome.) If you find that too boring, you can hang framed mirrors in various styles (goes with a cottagey, Victorian look - not a modern style.)

Your mirror to expand space and light does NOT have to be above the sink (mine was on the wall over the toilet.) I prefer to have a medicine cabinet above the sink. Use one with a mirrored door. If you own, or can work with the landlord, install one with a white frame that can be inserted partway into the wall between studs - takes up less space.) If the place is older and the space small, you can find recessed steel ones with mirrored doors that are vintage and smaller than new ones.

2. You want as much white as possible. Walls, ceilings (mine included white floor tiles, and white wall and shower tiles with black accents.) Then use the textile items to add color (you can change this whenever you want.) Monocolor, not too dark is best. I went with yellow - yellow shower curtain, bathmat, and yellow and white towels, with some green towels. White and yellow expanded the light and space. Dark colors (like the green) did not. Small black accents are fine if you have enough light.

3. Chrome: Add as much chrome as possible - it reflects light. I added a Mayfair white wood toilet seat with two chrome hinges (seems I need to replace a yucky one in every place I move into - I've decided this one is most durable, and the chrome is way better than plastic hinges).

Also, I had a chrome-colored shower curtain rod that I screwed into the tiles to replace the spring-loaded one that was there when I moved in and was always falling down (shiny is what you are going for) - if I had to do it again, I might install one of those curved ones that you see in hotels sometimes). Also, same chrome color for shower curtain hooks.

Also purchased chrome-colored 3-tier wire stand (designed for shower corners, but equally usable on the floor of a small bathroom, or in a small corner) that allowed for more open storage - visually less large than a closed cabinet would be, and fit in a really small space.

Other accents: Chrome-colored stainless steel drinking glass (unbreakable), toilet paper holder, garbage can, etc.

I had chrome colored faucets, so I went with this as my metal color. If you have gold or brass, then go with that metal color.

4. Other furniture: If you have room for a floor cabinet, get a white one. If it has glass doors, cover the inside of the doors in fabric or wrapping paper in your textile colors.

5. Less clutter - Visually and actually. I installed a chrome-colored tall pole with baskets in the corner of the tub/shower - keeps a lot of stuff in one place, and you can hide it behind the shower curtain when you have company.

6. Additional accents: choose one color of wood and go with that only. Bamboo is light-colored, so will increase light reflection and not soak it up, and there are lots of items available in it now.

7. I'd avoid framed art. Go with mirrors, chrome-colored accents you can intall on walls (towel rails, hooks, retractable mirror, candle holders, etc.) Small art pieces - like decorative tiles meant to be hung - are nice.

8. Fabric: Use nice fabric for other items. I've used a piece of French yellow and green fabric for a curtain to cover recessed shelves in one bath, and used the same piece of fabric to make a sink skirt on an old wall-hung sink in another (covers the ugly rusting pipes, and creates a closed storage area - and the fabric sticks onto the old cast-iron sink with magnets - and looks great.)

9. Light: If you are renting and can't add light fixtures,you can often just change the shade on fixtures easily. Large white ones with shed the most light.

You can also get either a small table lamp to set on a floor cabinet, or a light sconce-type light that can be hung on a nail on the wall. (Keep cords out of the way, affixed to wall so no one trips on them.)

All of these suggestions are so helpful! Our bathrooms don't have windows either. And they both have exterior walls. And a perfect space for a window. When I mentioned installing them to my husband, he balked. SO, I will be using all of these helpful hints instead!

Mirrors a a good suggestion, but nothing will beat overhead lighting. I have drop ceilings with flourescent lighting and it's great.

@0design0newbie0, don't take no for an answer from your husband - at least get a date for when you can start (& finish) work on making windows!
I'm delighted to see this post as I have the same problem myself - recently moved into a rental with my boyfriend in France. I have loads of ideas for the rest of the apartment but no great ones for the bathroom. It has white wall tile with aqua accents, and speckled beige-cream floor tile. It also doubles as a laundry room!
I've thought of: staying with the aqua theme, with bamboo/wicker accessories; aqua + bright red; aqua + orange; aqua + yellow + white... yeah, I'm a bit lost!!
I'll try post a link to some photos for any comments, and in the meantime will gobble up the comments on the original post here too!!
http://www.facebook.com/album.php?aid=539456&id=593045622&l=677cf60e37

I also have a windowless bathroom, and my bright blue/green polka-dotted shower curtain always makes me smile! The shower curtain combined with some fun art and a great rug/mat make the bathroom feel colorful and fun. And in the end, you don't spend that much time in the bathroom anyway.

Replace the existing door with a frosted glass panel door.

We have a very large, but also very dark bathroom with no windows. For some reason unbeknownst to me, they felt canister lighting would be great, but didn't think it was necessary to put a light in the shower which is quite a distance away from the canister lights over the sink. We can't paint or add fixtures and, while bright accessories are great, it's still quite difficult to shave your legs when you can't see what you're doing. I'm starting to get used to showering in the dark, but I wish there was some way of fixing this problem.

For several years I lived in an apartment with a window in the bathroom. I added a lot of light colors and accessories and installed bathroom lighting fixtures not just above the mirror but around the room. I wish I still had pictures.