If you can already see the texture of the existing wallpaper through the layer of paint, then the texture could also come through the new layer of wallpaper. If that’s the aesthetic you want, then proceed. But if you want a smoother surface, you should either strip off the existing paint and wallpaper or hang a layer of liner paper before proceeding.

Yes, you can put wallpaper in a bathroom, but whether it's a good idea depends on several factors. Because bathrooms are high-humidity areas, it's crucial to choose a water-resistant wallpaper, such as one made of vinyl. Proper wall preparation is also critical to ensure the paper adheres well, even after many steamy showers. The wallpaper's placement also affects its longevity; it will hold up better on an accent wall or away from direct water contact, rather than immediately next to a shower. A well-ventilated bathroom will yield the best results.

Darker walls may make tight bathrooms appear even smaller, but one dark accent wall can really make a bathroom pop. Wallpaper with a dark background can add intrigue and sophistication. Still, if you’re looking to open the room up and give it a modern, airy feeling, light colors may work best for your needs. Although there are some popular and unpopular opinions, there’s really no “should” when it comes to personal design choice. 

Accent walls have been a popular decor choice over the past two decades, and they don’t seem to be going out of style any time soon. They’re a quick and easy way to change the mood of the room without committing to painting every wall, and many homeowners like the visual interest they add to a room.