Although you can complete a closet frame in just an afternoon, finishing the entire closet will take a few days to a week. However, that’s still not as much as the average time it takes to remodel a closet, which can take anywhere from several weeks to more than a month. That’s because you also have to consider the time it will take to demolish the existing space, plan a new design, order materials, and actually install it. 

You can turn an adjacent room into a walking closet by just rearranging the room. This means removing the furniture and adding racks and an island in the center if you have that in your budget. Houses with two bedrooms connected to each other are great options for large walk-in closets that don't require any structural changes or much building whatsoever.

You can design your own closet, but it’s usually better to hire a professional to do the work for you. Not only will you get years of design experience to guide you toward the right layout and material choices, but you’ll also only pay slightly more hiring a professional than you would creating your own plans and hiring a carpenter. A high-quality closet designer can provide insight into how to lay out your closet, and they may be able to find you a good deal on the carpentry or complete the work using an affordable, in-house team.

A standard walk-in closet has dimensions of 7 feet by 10 feet at a minimum and an average of 100 square feet. Remember that the dimensions of the closet aren’t necessarily the usable space. This means that a 100-square-foot walk-in closet with shelves on each wall and an island may only have a walkable area of 50 square feet or less. Make sure you consider the effect of additions when you plan the room—mockups are a great idea.