1) Sliding Doors
Sliding doors are great for small spaces. In the kitchen, a sliding door is used for the pantry; where a regular door on a hinge requires space in front of the door to open properly, the sliding door only requires room to slide to either side of the opening. If you're short on kitchen space, consider a sliding door for the pantry.
2) Barn Door
The barn door (despite its name) is typically an interior sliding door. Most real barn doors are sliding doors to make it easy for one person to open and close a door while moving large animals and farm equipment in and out of a barn. The functionality and rustic charm translates well into interior design. It's space-saving, versatile and adds homey character. For rooms with many doors, like a bathroom, the barn door eliminates door clusters in spaces that can otherwise be used for bathroom storage. As a DIY project, barn doors are fairly simple to assemble, but using a reclaimed barn door adds a touch more style.
3) Dutch Door
The Dutch door originated in the Netherlands. It is one door split in half horizontally so the top can be open while the bottom remains closed. In the 1700s, this allowed fresh air to flow into the home without letting animals in. It is allegedly the precursor to the screen door. Today they're more of a decorative piece than a functional piece. The door adds an unexpected allure and for the person who loves the breeze on a summer night, it gives you the option of leaving the door open without the dread of what might wander in.
4) Faux Panels
Flat, hollow core doors are inexpensive, light and easy to deal with, but they're not easy on the eye; a few faux panels can change that. The panels give the illusion of a stile and rail door, which is classy, classic and far more attractive than a flat, hollow core door. Whether you add two panels or four, it's a relatively simple project that will leave you with a door with a little more dimension and character.
5) Adding a Window to a Door
Letting light through an interior door is a way to make a room or hallway feel more open and less closed off. It gives character to a bedroom or adds light to a gloomy room. For bathrooms, a frosted window works to give a new layer of design and brightness to the room without sacrificing privacy. If you're willing to put in the work, it's worth it for the added adornment.